- Synthesis of unsymmetrical N-(2-tert-butylphenyl)-N-(4-tert-butylphenyl)nitroxyl radical, the first stable diarylnitroxyl with vacant para-position
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The title compound, first example of a stable diarylnitroxyl with vacant para-position, was best synthesized by CuCl-assisted coupling of o-tert-butylnitrosobenzene and p-tert-butylphenylboronic acid followed by N-xidation of the thus obtained unsymmetrical diarylamine. ESR investigation showed that ortho-substituted aromatic ring is removed from the conjugation plane providing unusual stability of this radical.
- Levitskiy, Oleg A.,Sentyurin, Vyacheslav V.,Bogdanov, Alexey V.,Magdesieva, Tatiana V.
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- tert-Butylated spirobifluorene derivative incorporating triphenylamine groups: A deep-blue emitter with high thermal stability and good hole transport ability for organic light emitting diode applications
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Abstract A tert-butylated spirobifluorene derivative incorporating triphenylamine groups was synthesized starting from the readily available reagent biphenyl. Without any hole-transport layer, an unoptimized double-layer device exhibits excellent electroluminescent performances with a radiance of 3013 cd/m2 at 9.8 V, a maximum electroluminescent efficiency of 1.71 cd/A, a maximal external quantum efficiency of 2.58% at a brightness of 4.8 cd/m2, narrow full width at half-maximum (54 nm), and blue emission with Commission Internationale de l'Eclairage coordinates of (0.152, 0.103), which is close to the standard for blue. Compared to the reported organic light emitting diodes materials, the molecule displays very high thermal stability. In addition, the bilayer device showed a greatly improved performance as compared to a trilayer device with NPB as hole-transporting layer, which indicated that the molecule possesses good hole transport ability and can be good candidate for hole-transporting layer in organic light emitting diodes.
- Xiao, Haibo,Ding, Lei,Ruan, Dong,Li, Benyan,Ding, Ning,Ma, Dongge
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- Oxidative homocoupling reaction of aryltrimethylsilanes by Pd/o-chloranil catalysis
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A practical oxidative homocoupling reaction of aryltri-methylsilanes has been achieved by Pd/o-chloranil catalytic system. The reaction shows the good functional group tolerability toward bromo, fluoro, ester, and methoxy groups to give a series of biaryls bearing electron-withdrawing and -donating groups. The boronate group is also retained on biaryls without any ArB bond cleavage, which is highly advantageous for orthogonal coupling.
- Shibata, Mari,Ito, Hideto,Itami, Kenichiro
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- Shape-selective alkylation of biphenyl over H-[Al]-SSZ-24 zeolites with AFI topology
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H-[Al]-SSZ-24 zeolites with AFI topology were synthesized through the alumination of [B]-SSZ-24 zeolites, and applied for the alkylation of biphenyl (BP). H-[Al]-SSZ-24 zeolites have high activity for the isopropylation. The shape-selective formation of 4,4′-diisopropylbiphenyl (4,40-DIPB) occurred at moderate temperature; however, the selectivity for 4,40-DIPB decreased with an increase in the reaction temperature. Isomerization of 4,4′-DIPB occurred at higher temperatures over internal and external acid sites when there are enough acid sites inside the channels. The channels can discriminate 4,4′-DIPB from the other DIPB isomers in their transition states; however, they can not prevent the isomerization of 4,4′-DIPB at higher temperatures. The selectivity for the least bulky 4,4′-dialkylbiphenyl increased with the bulkiness of alkylating agents in the order: isopropylation s-butylation t-butylation. These results strongly support the shape-selective formation of the least bulky products inside the channels of H-[Al]-SSZ-24 zeolites.
- Ito, Akira,Maekawa, Hiroyoshi,Kawagoe, Hiroaki,Komura, Kenichi,Kubota, Yoshihiro,Sugi, Yoshihiro
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- Hydride Transfer to Gold: Yes or No? Exploring the Unexpected Versatility of Au???H?M Bonding in Heterobimetallic Dihydrides
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The potential for coordination and H-transfer from Cp2MH2 (M=Zr, W) to gold(I) and gold(III) complexes was explored in a combined experimental and computational study. [(L)Au]+ cations react with Cp2WH2 giving [(L)Au(κ2-H2WCp2)]+ (L=IPr (1), cyclic (alkyl)(amino)carbene (2), PPh3 (3) and Dalphos-Me (4) [IPr=1,3-bis(diisopropylphenyl)imidazolylidene; Dalphos-Me=di(1-adamantyl)-2-(dimethylamino)phenyl-phosphine], while [Au(DMAP)2]+ (DMAP=p-dimethylaminopyridine) affords the C2-symmetric [Au(κ-H2WCp2)2]+ (5). The Dalphos complex 4 can be protonated to give the bicationic adduct 4 H, showing AuI???H+?N hydrogen bonding. The gold(III) Lewis acid [(C^N?CH)Au(C6F5)(OEt2)]+ binds Cp2WH2 to give an Au-H-W σ-complex. By contrast, the pincer species [(C^N^C)Au]+ adds Cp2WH2 by a purely dative W→Au bond, without Au???H interaction. The biphenylyl-based chelate [(C^C)Au]+ forms [(C^C)Au(μ-H)2WCp2]+, with two 2-electron-3-centre W?H???Au interactions and practically no Au?W donor acceptor contribution. In all these complexes, strong but polarized W?H bonds are maintained, without H-transfer to gold. On the other hand, the reactions of Cp2ZrH2 with gold complexes led in all cases to rapid H-transfer and formation of gold hydrides. Relativistic DFT calculations were used to rationalize the striking reactivity and bonding differences in these heterobimetallic hydride complexes along with an analysis of their characteristic NMR parameters and UV/Vis absorption properties.
- Rocchigiani, Luca,Klooster, Wim T.,Coles, Simon J.,Hughes, David L.,Hrobárik, Peter,Bochmann, Manfred
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- Nickel-Catalyzed Reductive Dicarbofunctionalization of Alkenes
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An intermolecular, three-component reductive dicarbofunctionalization of alkenes is presented here. The combination of Ni catalysis with TDAE as final reductant enables the direct formation of Csp3-Csp3 and Csp3-Csp2 bonds across a variety of π-systems using two different electrophiles that are sequentially activated with exquisite selectivity under mild reaction conditions.
- García-Domínguez, Andrés,Li, Zhaodong,Nevado, Cristina
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- Rapid Ligand-Free Base-Accelerated Copper-Catalyzed Homocoupling Reaction of Arylboronic Acids
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A rapid, ligand-free, base-accelerated, copper-catalyzed homocoupling reaction of (het)arylboronic acids is presented. A -CuCl2·2H2O/Na2CO3-based catalyst enabled the formation of bi(het)aryl compounds by a homocoupling process in moderate to excellent yields (72-97%) within 15 minutes. A mechanism for the copper-catalyzed base-accelerated reaction is proposed.
- Cao, Ya-Nan,Tian, Xin-Chuan,Chen, Xing-Xiu,Yao, Yun-Xin,Gao, Feng,Zhou, Xian-Li
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- Homocoupling of arylboronic acids with a catalyst system consisting of a palladium(II) N-heterocyclic carbene complex and p-benzoquinone
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In the presence of 1-3 mol% SIPr-ligated Pd(OAc)2 and 0.6 equivalent of p-benzoquinone, various arylboronic acids underwent homocoupling in MeOH at ambient temperature to produce symmetrical biaryls in 38-96% yields. Georg Thieme Verlag Stuttgart.
- Yamamoto, Yoshihiko
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- Kinetically Controlled Reticular Assembly of a Chemically Stable Mesoporous Ni(II)-Pyrazolate Metal-Organic Framework
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The application scope of metal-organic frameworks (MOFs) is severely restricted by their weak chemical stability and limited pore size. A robust MOF with large mesopores is highly desired, yet poses a great synthetic challenge. Herein, two chemically stable Ni(II)-pyrazolate MOFs, BUT-32 and -33, were constructed from a conformation-matched elongated pyrazolate ligand through the isoreticular expansion. The two MOFs share the same sodalite-type net, but have different pore sizes due to the network interpenetration in BUT-32. Controlled syntheses of the two MOFs have been achieved through precisely tuning reaction conditions, where the microporous BUT-32 was demonstrated to be a thermodynamically stable product while the mesoporous BUT-33 is kinetically favored. To date, BUT-32 represents the first example of Ni4-pyrazolate MOF whose structure was unambiguously determined by single-crystal X-ray diffraction. Interestingly, the kinetic product BUT-33 integrates 2.6 nm large mesopores with accessible Ni(II) active sites and remarkable chemical stability even in 4 M NaOH aqueous solution and 1 M Grignard reagent. This MOF thus demonstrated an excellent catalytic performance in carbon-carbon coupling reactions, superior to other Ni(II)-MOFs including BUT-32. These findings highlight the importance of kinetic control in the reticular synthesis of mesoporous MOFs, as well as their superiority in heterogeneous catalysis.
- He, Tao,Huang, Zhehao,Yuan, Shuai,Lv, Xiu-Liang,Kong, Xiang-Jing,Zou, Xiaodong,Zhou, Hong-Cai,Li, Jian-Rong
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- The alkylation of biphenyl over fourteen-membered ring zeolites. the influence of zeolite structure and alkylating agent on the selectivity for 4,4′-dialkylbiphenyl
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Alkylation, i.e. isopropylation, s-butylation, and t-butylation, of biphenyl (BP) was examined over fourteen-mem-bered ring (14-MR) zeolites, CIT-5, UTD-1, and SSZ-53, in order to elucidate the relationships between structure of zeolites and bulkiness of alkylating agents on the shape-selective catalysis. CIT-5 zeolite (CFI) yielded 4,4′-diisopropyl- biphenyl (4,4′-DIPB) in the level of 50-60% in the isopropylation in the range of 150-300°C. 2,2′-, 2,3′-, and 2,4′-DIPB (2,x′-DIPB) isomers were obtained as the predominant DIPB isomers at lower temperatures, and the formation of 3,4′- and 3,3′-DIPB isomers increased with an increase in the temperature. However, the selectivities were in the level of 10- 15% for UTD-1 (DON) and SSZ-53 (SFH) zeolites in the range of 150-350°C. The s-butylation with 1-butene gave results similar to the isopropylation, although the selectivities for 4,4′-di-s-butylbiphenyl (4,4′-DSBB) were higher than those for 4,4′-DIPB at 250 °C: 80-85% for CFI, 40-50% for DON, and 30-40% for SFH. High selectivity for 4,4′-di-f-butylbiphenyl (4,4′-DTBB) was observed in the f-butylation at 250 °C: 95% for CFI, 90% for DON, and 80% for SFH. These differences are due to the spatial difference in their channels, and also due to bulkiness of alkylating agents, propene, 1-butene, and 2-methylpropene. The selectivity for 4,4′- dialkylbiphenyl (4,4′-DABP) was governed by the exclusion of the bulky DABP isomers at the transition state by steric restriction in the zeolite channels.
- Sugi, Yoshihiro,Maekawa, Hiroyoshi,Mulla, Shafeek Abdul Rashid,Ito, Akira,Naitoh, Chikayo,Nakagawa, Kazunori,Komura, Kenichi,Kubota, Yoshihiro,Kim, Jong-Ho,Seo, Gon
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- Nickel-catalyzed coupling of aryl bromides in the presence of alkyllithium reagents
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An easy approach towards the synthesis of compounds using coupling reactions of bromide compounds was demonstrated. A comparison of different alkyllithium reagents was made by examining the coupling of bromobenzene (1a). The molar ratio of bromobenzene to catalyst was 138:1 using [NiCl 2(dppp)] and bromobenzene, Bpy was added to the reaction solution as a ligand. Alkyllithium was added at half molar equivalents to that of phenyl bromide groups with the intention of generating an equimolar ratio of lithiated benzene anions to unreacted phenyl bromide groups. It was observed that decreasing the amount of [NiCl2(dppp)] from 25 to 12 mg, while maintaining the ratio to bpy, did not have a substantial effect on the yield of biphenyl formed. The one-pot synthetic technique demonstrate the use of alkyllithium reagents with a catalytic amount of nickel to syntheisze coupled aryl compounds.
- Jhaveri, Sarav B.,Carter, Kenneth R.
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- Photochemische Untersuchungen an substituierten 2-Bis(diphenylstibino)methan>bis(phenyl)platin(II)-Verbindungen
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The photochemical reactivity of the complexes 2-bis(diphenylstibino)methane>bis(phenyl)platinum(II) (4a-f) complexes having the substituents CH3, CH(CH3)2, C(CH3)3, Br, F, CF3 in the para-positions of the platinum-bonded phenyl rings has been
- Brune, Hans-Albert,Klotzbuecher, Rainer,Schmidtberg, Guenther
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- A practical one-pot synthesis of soluble hexa-peri-hexabenzocoronene and isolation of its cation-radical salt
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A simple and practical synthesis of soluble hexaperi-hexabenzocoronene (HBC) from readily available hexaphenylbenzene (HPB) is described. In this simple procedure, the substitution of the free para positions of the propeller-shaped HPB with tert-butyl groups and the oxidative cyclodehydrogenation to planar HBC is achieved in a one-pot reaction using ferric chloride both as a Lewis acid catalyst and as an oxidant in excellent yields. The ready availability of HBC allows the isolation of its pure cation-radical salt using a variety of chemical oxidants such as antimony pentachloride and triethyloxonium and nitrosonium hexachloroantimonate salts.
- Rathore, Rajendra,Burns, Carrie L.
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- Synthesis of bisbicyclo[1.1.1]pentyldiazene. The smallest bridgehead diazene
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Bisbicyclo[1.1.1]pentyldiazene, the smallest bicyclic azo compound, has been synthesized from the precursor [1.1.1]propellane via synthesis of N,N′-bis(bicyclo[1.1.1]pentyl)sulfamide and azoxybicyclo[1.1.1]pentane. The UV absorption of this diazene at 382 nm indicates that the compound is the trans isomer. Conversion to the cis isomer by irradiation was not possible because of attainment of a photostationary state. However, on the basis of the photochemical studies, the absorption of the cis-[1.1.1] isomer is estimated to be 384 nm.
- Hossain,Timberlake
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- Homocoupling of aryl halides using catalytic system of palladium and phosphite
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The palladium-catalyzed homocoupling of aryl halides was carried out using phosphite ligands. The optimized reaction conditions were Pd2(dba)3, phosphite 1, and NaOt-Bu in diglyme, and the desired homocoupling products were afforded in moderate to good yields. Copyright
- Moon, Jeongju,Nam, Hyungoog,Ju, Jinhun,Jeong, Miso,Lee, Sunwoo
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- Structural and catalytic properties of the [Ni(BIPHEP)X2] complexes, BIPHEP = 2,2-diphenylphosphino-1,1-biphenyl; X = Cl, Br
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The synthesis and catalytic properties in Kumada C–C coupling of the [Ni(BIPHEP)X2] complexes, X = Cl (1), Br (2), are described. The crystal structures of the BIPHEP ligand and 2 are also presented and compared with previously reported crystal structures of atropisomeric bidentate phosphine ligands (P,P) and related [M(P,P)X2] complexes (M = Ni, Pd, Pt). BIPHEP crystallizes in the C2/c space group, with both enantiomers present in the unit cell. This is consistent with BIPHEP being a “tropos” ligand. Complex 2 crystallizes in the P21/a space group. There are two symmetry-independent molecules in the asymmetric unit, namely 2a and 2b, in which the BIPHEP ligand adopts the S or the R configuration, respectively. Complexes 2a and 2b exhibit a severely tetrahedrally-distorted square planar NiP2Br2 coordination sphere, with a PNiP bite angle of 93.3° and 94.7°, respectively. The observed catalytic behavior of complexes 1 and 2 in the Kumada coupling between p-tert-butyl-halogenobenzene and p-tolylmagnesium chloride is benchmarked against that of [Ni(dppp)Cl2], dppp = 1,3-bis(diphenylphoshpino)propane. However, all three complexes are catalytically inactive in the Suzuki-Miyaura coupling reaction.
- Ioannou, Polydoros-Chrysovalantis,Grigoropoulos, Alexios,Stergiou, Konstantina,Raptopoulou, Catherine P.,Psycharis, Vassilis,Svoboda, Jan,Kyritsis, Panayotis,Vohlídal, Ji?í
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- Three oxidation states of the bis(3,5-di-tert-butyl-2-phenolato)azanido pincer ligand on chromium(III)
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Three monomeric complexes of chromium(III) containing the redox-active ligand derived from bis(3,5-di-tert-butyl-2-phenol)amine, [ONOcat]H3, were prepared and fully characterized. The potassium salt of [ONOq]1? reacted with CrCl3(THF)3 to afford [ONOq]CrCl2(THF) (1); whereas, the trilithium salt of [ONOcat]3? reacted with CrCl3(THF)3 in the presence of pyridine to afford [ONOcat]Cr(py)3 (3). The three electron series was completed by reacting 1 with K[bpy[rad]] to afford [ONOsq[rad]]CrCl(bpy) (2). All three members of the series were characterized by structural, spectroscopic, and electrochemical methods. Attempts to effect the two-electron reduction of 1 resulted in the formation of a bimetallic chromium complex, {[ONOcat]Cr(py)2}2 (4), which was also structurally characterized. The reaction of 1 with aryl transfer reagents resulted in a mixture of one- and two-electron reactivity, comprising the expulsion of either phenyl radical or biphenyl from the chromium coordination sphere.
- Hollas, Aaron M.,Ziller, Joseph W.,Heyduk, Alan F.
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- Synthesis and characterization of highly soluble and oxygen permeable new polyimides based on twisted biphenyl dianhydride and spirobifluorene diamine
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The novel spirobifluorene diamine monomer, 2,7-bis-amino-2′,7′- di-tert-butyl-9,9′-spirobifluorene, was obtained. The new organosoluble polyimides were prepared from spirobifluorene diamine containing bulky tert-butyl group and conventional dianhydrides as well as 2,2- ′bis(4″-tert-butylphenyl)4,4′,5,5′- biphenyltetracarboxylic dianhydride (BBBPAn) and 2,2′-bis(4″- trimethylsilylphenyl)-4,4′,5,5′biphenyltetracarboxylic dianhydride (BTSBPAn), which are composed of a noncoplanar twisted biphenyl unit containing bulky p-tert-butylphenyl groups and/or p-trimethylsilylphenyl groups by high-temperature one step polymerization. The structures of polymers were confirmed by various spectroscopic techniques. The weight-average molecular weights and polydispersities of resulting polymers were in the ranges 48 300-183 900 and 2.10-3.26, respectively. The bulky and twisted noncoplanar structural feature confers an enhanced solubility of the polyimides because of a decrease in the degree of molecular packing and crystallinity while imparting a significant increase in both Tg and thermal stability by restricting segmental mobility. The new polyimides exhibit the high oxygen permeabilities (P(O2) = 18-121 barrer) and O2/N2 gas separation properties (P(O2)/P(N2) = 2.2-9).
- Kim, Yun-Hi,Kim, Hyung-Sun,Kwon, Soon-Ki
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- Exploration of Ionic Liquids as Soluble Supports for Organic Synthesis. Demonstration with a Suzuki Coupling Reaction
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(Equation Presented) The efficiency of ionic liquid supported synthesis was demonstrated by the Suzuki reaction of ionic liquid supported iodobenzoate compounds with arylboronic acids in aqueous media to give, after cleavage with ammonia/methanol, biaryl products in good yields and high purities, without the need for chromatographic purification.
- Miao, Weishi,Chan, Tak Hang
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- Electrochemical coupling halobenzene into biphenyl on a reusable Pd nanoparticle-coated carbon-paper electrode at ambient conditions
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Electrochemical organic synthesis (EOS) employing electrons to directly activate the reactants can readily complete the chemical conversion under mild conditions. Here, it presented an efficient electrochemical coupling halobenzene into biphenyl on a Pd nanoparticle-coated cathode. The biphenyl product can be obtained with a yield up to 77% at 35 mA, 6 h (3.9 F mol?1). In addition, after consecutive fifth run of the coupling reaction, the yield still remained atca.40%, suggesting its considerable recyclable capacity. In addition, the preliminary kinetics studyviathe off-line gas chromatography analysis of the reaction mixture shows a two-section reaction process, including the introduction process (IP) and fast conversion process (FCP). Further, the estimated reaction kinetics constant value of 0.196 min?1for FCP suggests a more effective conversion than that obtained by the previous study. This study adopts a simple way to fabricate a low-cost and reusable Pd electrode, achieving a high-efficiency electrochemical strategy for the Ullmann-type coupling reaction at mild conditions, and holds a great promise to extend this synthesis route to other important organic synthesis.
- Wang, Chao-Nan,Lu, Yong-Heng,Liu, Yue,Liu, Jun,Yang, Yao-Yue,Zhao, Zhi-Gang
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- Reductive Coupling of Aryl Halides via C—H Activation of Indene
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This paper describes the first case of a reductive coupling reaction with indene, a non-heteroatom olefin used as a reducing agent. The scope of the substrate is wide. The homo-coupling, cross-coupling, and synthesis of 12 and 14-membered rings were realized. The control experiment, indene-product curve and density functional theory calculations showed that the η3-palladium indene intermediate was formed by C—H activation in the presence of cesium carbonate. We speculate that the final product was obtained through a Pd (IV) intermediate or aryl ligand exchange. In addition, we excluded the formation of palladium anion (Pd(0)?) intermediates.
- Zhang, Bo-Sheng,Yang, Ying-Hui,Wang, Fan,Gou, Xue-Ya,Wang, Xi-Cun,Liang, Yong-Min,Li, Yuke,Quan, Zheng-Jun
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p. 1573 - 1579
(2021/05/28)
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- Tandem Mn–I Exchange and Homocoupling Processes Mediated by a Synergistically Operative Lithium Manganate
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Pairing lithium and manganese(II) to form lithium manganate [Li2Mn(CH2SiMe3)4] enables the efficient direct Mn–I exchange of aryliodides, affording transient (aryl)lithium manganate intermediates which in turn undergo spontaneous C?C homocoupling at room temperature to furnish symmetrical (bis)aryls in good yields under mild reaction conditions. The combination of EPR with X-ray crystallographic studies has revealed the mixed Li/Mn constitution of the organometallic intermediates involved in these reactions, including the homocoupling step which had previously been thought to occur via a single-metal Mn aryl species. These studies show Li and Mn working together in a synergistic manner to facilitate both the Mn–I exchange and the C?C bond-forming steps. Both steps are carefully synchronized, with the concomitant generation of the alkyliodide ICH2SiMe3 during the Mn–I exchange being essential to the aryl homocoupling process, wherein it serves as an in situ generated oxidant.
- Uzelac, Marina,Mastropierro, Pasquale,de Tullio, Marco,Borilovic, Ivana,Tarrés, Màrius,Kennedy, Alan R.,Aromí, Guillem,Hevia, Eva
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supporting information
p. 3247 - 3253
(2020/12/11)
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- Pd-Catalyzed Cross-Coupling of Organostibines with Styrenes to Give Unsymmetric (E)-Stilbenes and (1 E,3 E)-1,4-Diarylbuta-1,3-dienes and Fluorescence Properties of the Products
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A general and effective palladium-catalyzed cross-coupling of organostibines with styrenes to give (E)-olefins was disclosed. By the use of an organostibine reagent, this method can produce unsymmetric (E)-1,2-diarylethylenes and (1E,3E)-1,4-diarylbuta-1,3-dienes in good yields with high E/Z selectivity and good functional group tolerance. Resveratrol and DMU-212 were synthesized in high yield. The protocol can be extended to the synthesis of (1E,3E,5E)-1,6-diphenylhexa-1,3,5-triene in 40% yield. Products 5e, 5f, and 7a showed good photoluminescence quantum yields ranging from 72 to 99%.
- Zhang, Zhao,Zhang, Dejiang,Zhu, Longzhi,Zeng, Dishu,Kambe, Nobuaki,Qiu, Renhua
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supporting information
p. 5317 - 5322
(2021/06/28)
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- Porphyrin n-pincer pd(Ii)-complexes in water: A base-free and nature-inspired protocol for the oxidative self-coupling of potassium aryltrifluoroborates in open-air
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Metalloporphyrins (and porphyrins) are well known as pigments of life in nature, since representatives of this group include chlorophylls (Mg-porphyrins) and heme (Fe-porphyrins). Hence, the construction of chemistry based on these substances can be based on the imitation of biological systems. Inspired by nature, in this article we present the preparation of five different porphyrin, meso-tetraphenylporphyrin (TPP), meso-tetra(p-anisyl)porphyrin (TpAP), tetra-sodium meso-tetra(p-sulfonatophenyl)porphyrin (TSTpSPP), meso-tetra(m-hydroxyphenyl)porphyrin (TmHPP), and meso-tetra(m-carboxyphenyl)porphyrin (TmCPP) as well as their N-pincer Pd(II)-complexes such as Pd(II)-meso-tetraphenylporphyrin (PdTPP), Pd(II)-meso-tetra(p-anisyl)porphyrin (PdTpAP), Pd(II)-tetrasodium meso-tetra(p-sulfonatophenyl)porphyrin (PdTSTpSPP), Pd(II)-meso-tetra(m-hydroxyphenyl)porphyrin (PdTmHPP), and Pd(II)-meso-tetra(m-carboxyphenyl)porphyrin (PdTmCPP). These porphyrin N-pincer Pd(II)-complexes were studied and found to be effective in the base-free self-coupling reactions of potassium aryltrifluoroborates (PATFBs) in water at ambient conditions. The catalysts and the products (symmetrical biaryls) were characterized using their spectral data. The high yields of the biaryls, the bio-mimicking conditions, good substrate feasibility, evading the use of base, easy preparation and handling of catalysts, and the application of aqueous media, all make this protocol very attractive from a sustainability and cost-effective standpoint.
- Hanafiah, Marlia M.,Lakkaboyana, Sivarama Krishna,Lakshmidevi, Jangam,Marella, Ravi Kumar,Naidu, Bandameeda Ramesh,Prasad, Sana Siva,Venkateswarlu, Katta
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- Pd-catalyzed oxidative homocoupling of arylboronic acids in WEPA: A sustainable access to symmetrical biaryls under added base and ligand-free ambient conditions
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Symmetrical and unsymmetrical biaryls comprises a diverse class of biologically eloquent organic compounds. We herein report, a quick and eco-friendly protocol for the synthesis of biaryls by an oxidative (aerobic) homocoupling of arylboronic acids (ABAs) using Pd(OAc)2 in water extract of pomogranate ash (WEPA) as an efficient agro-waste(bio)-derived aqueous (basic) media. The reactions were executed at ambient aerobic conditions in the absence of external base and ligand to result symmetrical biaryls in excellent yields. The use of renewable media with an effective exploitation of waste, short reaction times, excellent yields of products, easy separation of the products, unnecessating the external base, oxidant, ligand or volatile organic solvents and ambient reaction conditions are the vital insights of the present protocol.
- Appa, Rama Moorthy,Lakshmidevi, Jangam,Naidu, Bandameeda Ramesh,Venkateswarlu, Katta
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- Palladium/Sensory Component-Catalyzed Homocoupling Reactions of Aryl Halides
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A novel and efficient catalyst system was developed for homocoupling reactions of aryl halides. The catalyst system consists of Pd(OAc) 2and the peppery sensory component of tobacco leaves. This is the first time that a sensory component has been used in an organic reaction. Experiments using the catalyst system showed that the reactions proceeded smoothly under air in the absence of both an additional ligand and a reductant. Furthermore, the catalyst system can be applied to the coupling reactions of hetaryl iodides. Many functional groups (including a hydroxy group) are tolerated.
- Bai, Haixin,Bao, Fengyu,Chai, Guobi,Liu, Pengfei,Liu, Zhikai,Zhang, Haiyan,Zhang, Qidong
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supporting information
(2020/09/09)
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- Metal-free synthesis of biarenes via photoextrusion in di(tri)aryl phosphates
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A metal-free route for the synthesis of biarenes has been developed. The approach is based on the photoextrusion of a phosphate moiety occurring upon irradiation of biaryl- A nd triaryl phosphates. The reaction involves an exciplex as the intermediate and it is especially suitable for the preparation of electron-rich biarenes.
- Qrareya, Hisham,Meazza, Lorenzo,Protti, Stefano,Fagnoni, Maurizio
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supporting information
p. 3008 - 3014
(2021/01/18)
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- Transition-Metal-Free Oxidative Cross-Coupling of Tetraarylborates to Biaryls Using Organic Oxidants
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Readily prepared tetraarylborates undergo selective (cross)-coupling through oxidation with Bobbitt's salt to give symmetric and unsymmetric biaryls. The organic oxoammonium salt can be used either as a stoichiometric oxidant or as a catalyst in combination with in situ generated NO2 and molecular oxygen as the terminal oxidant. For selected cases, oxidative coupling is also possible with NO2/O2 without any additional nitroxide-based cocatalyst. Transition-metal-free catalytic oxidative ligand cross-coupling of tetraarylborates is unprecedented and the introduced method provides access to various biaryl and heterobiaryl systems.
- Gerleve, Carolin,Studer, Armido
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supporting information
p. 15468 - 15473
(2020/05/06)
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- Synthesis method of biphenyl compounds
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The invention discloses a synthesis method of biphenyl compounds. The synthesis method comprises the following steps: by using an aromatic boric acid as a reaction substrate and palladium as a catalyst, adding a catalytic amount of a phase transfer catalyst, reacting in a sodium hypochlorite water solution at 50 DEG C for 1-5 hours, carrying out oxidative coupling, and carrying out post-reaction treatment to obtain a target product biphenyl compound. The method has the characteristics of mild reaction conditions, simplicity in operation and purification, wide substrate application range, highyield, high reaction speed and the like, and has practicability.
- -
-
Paragraph 0081-0097
(2020/02/06)
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- Efficient Pd-catalyzed oxidative homocoupling of arylboronic acids in aqueous NaClO
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An efficient, mild and practical method was developed for the synthesis of biaryls via the Pd-catalyzed oxidative homocoupling of aromatic/heteroaromatic boronic acids in aqueous NaClO.
- Li, Min-Xin,Tang, Yan-Ling,Gao, Hui,Mao, Ze-Wei
-
supporting information
(2020/03/04)
-
- Ni-Catalyzed Reductive Dicarbofunctionalization of Nonactivated Alkenes: Scope and Mechanistic Insights
-
Olefins devoid of directing or activating groups have been dicarbofunctionalized here with two electrophilic carbon sources under reductive conditions. Simultaneous formation of one C(sp3)-C(sp3) and one C(sp3)-C(sp2) bond across a variety of unbiased π-systems proceeds with exquisite selectivity by the combination of a Ni catalyst with TDAE as sacrificial reductant. Control experiments and computational studies revealed the feasibility of a radical-based mechanism involving, formally, two interconnected Ni(I)/Ni(III) processes and demonstrated the different ability of Ni(I) species (Ni(I)I vs PhNi(I)) to reduce the C(sp3)-I bond. The role of the reductant was also investigated in depth, suggesting that a one-electron reduction of Ni(II) species to Ni(I) is thermodynamically favored. Further, the preferential activation of alkyl vs aryl halides by ArNi(I) complexes as well as the high affinity of ArNi(II) for secondary over tertiary C-centered radicals explains the lack of undesired homo- and direct coupling products (Ar-Ar, Ar-Alk) in these transformations.
- Shu, Wei,García-Domínguez, Andrés,Quirós, M. Teresa,Mondal, Rahul,Cárdenas, Diego J.,Nevado, Cristina
-
supporting information
p. 13812 - 13821
(2019/09/10)
-
- Aerobic and Ligand-Free Manganese-Catalyzed Homocoupling of Arenes or Aryl Halides via in Situ Formation of Aryllithiums
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Ligand-free manganese-catalyzed homocoupling of arenes or aryl halides can be carried out under aerobic conditions via the in situ formation of the corresponding aryllithiums. A wide range of biaryls and derivatives has been obtained, and a mechanism involving monomeric manganese-oxo complexes has been proposed on the basis of DFT calculations.
- Liu, Yujia,Bergès, Julien,Zaid, Yassir,Chahdi, Fouad Ouazzani,Van Der Lee, Arie,Harakat, Dominique,Clot, Eric,Jaroschik, Florian,Taillefer, Marc
-
p. 4413 - 4420
(2019/03/26)
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- Photocatalytic coupled redox cycle for two organic transformations over Pd/carbon nitride composites
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Heterogeneous photocatalysis offers a means for "green" organic transformations. Generally, photogenerated electrons and holes are not utilized simultaneously and effectively. Here we report a coupling approach to promote simultaneously two organic transformations of the Ullmann C-C coupling reaction and the value-added aromatic alcohol oxidation reaction in inert solvent and under anaerobic conditions using a carbon nitride based composite (Pd/CN-450) prepared by loading Pd nanoparticles (NPs) on CN-450 (N defect and O dopant co-modified g-C3N4 with high crystallinity). Upon photo-excitation of the photocatalyst, the activation of carbon-halogen bonds of the adsorbed aryl halides can be promoted by the photogenerated electrons on Pd NPs and the aromatic alcohols undergo dissociation and dehydrogenation, and finally can be oxidized by the captured photogenerated holes from CN-450 in the presence of a Br?nsted base. N defects, O doping, and improved crystallinity, controlled by changing the post-annealing temperature in molten salts, enhance the visible light absorption and improve charger carrier separation of the functionalized carbon nitride. The smaller size and high dispersity of Pd NPs give the higher surface area-to-volume ratio resulting in efficient adsorption and activation of reactant molecules on Pd NPs and allow for the effective interfacial interaction of CN-450 with Pd NPs for promoting electron transfer from CN-450 to Pd NPs. As a result, Pd/CN-450 displays a superior photocatalytic activity of the coupled reaction compared to Pd/g-C3N4 (Pd NP supported pristine g-C3N4). Moreover, the coupled reaction system has general applicability for various substrates and shows reusability.
- Jia, Qiaohui,Zhang, Sufen,Jia, Xiaoxia,Dong, Xiaoyang,Gao, Ziwei,Gu, Quan
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p. 5077 - 5089
(2019/10/05)
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- Photolytic reactivity of organometallic chromium bipyridine complexes
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Known stable [Cr(bpy)2(Ph)2](BPh4) complexes undergo reductive elimination of biphenyl with visible-light photolysis using household incandescent or compact fluorescent light bulbs. A series of [Cr(R-bpy)2(Ar)2](X) complexes (R = H or CMe3; Ar = Ph, C6H4-CMe3, or C6H4-OMe; X = I, BPh4, or PF6) were prepared, and the effect of varying the bipyridine and aryl ligands on the UV-visible spectra and electrochemistry of the chromium(III) complexes was investigated. Photolysis of a mixture of two different bis(aryl) complexes gave only the homocoupled biaryl products by1H NMR and gas chromatography/mass spectrometry analysis. The initial product of photoinduced reductive elimination of [Cr(bpy)2(Ar)2](PF6) was trapped with bipyridine to generate [Cr(bpy)3](PF6) and with benzoyl peroxide to form [Cr(bpy)2(O2CPh)2](PF6). The latter chromium(III) bis(benzoate) complex was also synthesized by the addition of bipyridine and PhCO2H to Cp2Cr, followed by air oxidation. The neutral Cr(bpy)(S2CNMe2)Ph2complex also generated biphenyl upon visible-light photolysis. While the treatment of Cr(tBu-bpy)(dpm)Cl2[dpm = (OCtBu)2CH] with AgO2CPh gave trans-Cr(tBu-bpy)(dpm)(O2CPh)2, reaction of the dichloro precursor with PhMgCl produced anionic [Cr(tBu-bpy)Ph3]?with [Mg(dpm)(THF)4]+as the countercation, with both complexes characterized by single-crystal X-ray diffraction. Protonolysis of Cr(bpy)Ph3(THF) with 8-hydroxyquinoline produced Cr(bpy)(quin)Ph2, which generated biphenyl under visible-light photolysis, and the initial product of reductive elimination was trapped by bipyridine or benzoyl peroxide. A related Cr(bpy)(quin)2complex was synthesized by protonolysis of Cr(bpy)[N(SiMe3)2]2and characterized by single-crystal X-ray diffraction.
- Olafsen, Benjamin E.,Crescenzo, Giuseppe V.,Moisey, Luke P.,Patrick, Brian O.,Smith, Kevin M.
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p. 9611 - 9621
(2018/08/28)
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- A novel method for preparing S-(perfluoroalkyl)-dibenzothiophenium trifluoromethanesulfonate
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A method for preparing S-(perfluoroalkyl)-dibenzothiophenium trifluoromethanesulfonate shown as a general formula (I) by a one-pot process with significant effects is disclosed by the invention. The method includes reacting a biphenyl compound, perfluoroalkyl sulfonate, trifluoroacetic anhydride and trifluoromethanesulfonic acid. The biphenyl compound can be recovered and utilized so that the method is an environmentally friendly preparing method.
- -
-
Paragraph 0110-0113
(2018/04/01)
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- A ligand free protocol using Cu(OAc)2@Mont K-10 as versatile reusable catalyst for efficient homocoupling of arylboronic acids for synthesis of symmetric biaryls
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Biaryls are an important class of organic compounds that occur in many natural products and they have a wide variety of applications in drugs, agrochemicals, dyes, semi-conductors, and asymmetric syntheses. A versatile, eco-friendly, recyclable, heterogeneous catalyst has been developed for the efficient synthesis of symmetric biaryls from aryl boronic acids. The developed protocol for homocoupling of aryl boronic acid to symmetric biaryls is based on copper acetate supported on acid activated Mont K-10 which is ligand free, mild, inexpensive and compatible with wide range of functional groups and exhibit excellent yields. The catalyst is characterised by FTIR, ESR, XRD, SEM-EDX, BET surface area measurement and the catalyst can be separated from the reaction mixture by simple centrifugation and reused upto five cycles without significant loss in activity.
- Rahman, Taskia,Borah, Geetika,Gogoi, Pradip K.
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p. 795 - 800
(2020/06/26)
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- WEPA: a bio-derived medium for added base, π-acid and ligand free Ullmann coupling of aryl halides using Pd(OAc)2
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A bio-derived sustainable medium based on water extract of pomegranate ash (WEPA) has, for the first time, been developed for the homocoupling of aryl halides under palladium-assistance. Avoiding the requirement of an external base, ligand and π-acid, the use of the proposed renewable medium offers remarkable attributes like wide substrate scope, good to nearly quantitative yields of biphenyls with exceptional chemoselectivity and scale up viability.
- Lakshmidevi, Jangam,Appa, Rama Moorthy,Naidu, Bandameeda Ramesh,Prasad, S. Siva,Sarma, Loka Subramanyam,Venkateswarlu, Katta
-
supporting information
p. 12333 - 12336
(2018/11/30)
-
- One-pot two-step stannylation/Stille homocoupling of aryl bromides and iodides under solvent-free conditions
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A new highly efficient solvent-free method for aryl bromide (iodide) homocoupling comprising the use of Pd(OAc)2/PCy3 system in the presence of CsF is suitable for substrates bearing functional groups not tolerant to lithium-, magnesium-, zincorganic reagents and strong bases.
- Gribanov, Pavel S.,Golenko, Yulia D.,Topchiy, Maxim A.,Philippova, Anna N.,Kirilenko, Nikita Yu.,Krivoshchapov, Nikolai V.,Sterligov, Grigorii K.,Asachenko, Andrey F.,Bermeshev, Maxim V.,Nechaev, Mikhail S.
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p. 323 - 325
(2018/05/30)
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- Carbon-carbon bond forming reactions via Pd-catalyzed detellurative homocoupling of diorganyl tellurides
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A simple and highly efficient method for the constructions of Csp-Csp, Csp2-Csp2 and Csp3-Csp3 bonds is reported. The symmetrical diaryl tellurides undergo detellurative homocouplings to afford symmetrical biaryl products. The reactions are carried out at ambient temperature using PdCl2 as a catalyst in the presence of Ag2O and Na2CO3. Similarly, the detellurative homocouplings of dibenzyl telluride and bis(phenylethynyl)telluride give bibenzyl and the conjugated diyne, respectively.
- Zhang, Shaozhong,Kolluru, Lalitha,Vedula, Souseelya K.,Whippie, Drew,Jin, Jin
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p. 3594 - 3597
(2017/08/23)
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- Palladium-catalyzed reductive homocoupling of aryl sulfonates via cleavage of C─O bond at room temperature
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Palladium-catalyzed reductive homocoupling of aryl sulfonates has been successfully achieved under mild conditions. This transformation is a new method for the homocoupling reaction of aryl sulfonates at room temperature via the cleavage of C─O bonds, thus providing an alternative synthesis of symmetric biaryls. The reported reductive homocoupling reaction is tolerant of many common functional groups regardless of electron-donating or electron-withdrawing nature, making this newly developed transformation important for complementing Ullmann coupling. Experimental Section. Typical procedure for the products.
- Zhong, Shuangling,Chen, Mengxin,Liu, Ge,Sun, Chenggang,Liu, Wencong
-
-
- Copper-free palladium-catalysed desulfinative homocoupling of sodium arylsulfinates under mild and aerobic conditions
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A Pd(II)-catalysed homocoupling of sodium arylsulfinates has been successfully achieved under mild conditions. This transformation is a new method for the homocoupling reaction of sodium arylsulfinates, thus providing an alternative synthesis of symmetric biaryls. The reported homocoupling reaction is tolerant to many common functional groups, such as ester, halo, cyano and nitro and works well in the presence of electron-donating and electron-withdrawing substituents. Notably, the reported desulfinative homocoupling does not require Cu salts, ligands and bases, making this newly developed transformation attractive.
- Zhang, Wei
-
-
- Synthesis, characterization and crystal structure of Cu(II) complex of trans-cyclohexane-1,2-diamine: Application in synthesis of symmetrical biaryls
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A new Cu(II) complex [Cu(cyhxn)2(H2O)2][OTf]2 was synthesised by the reaction of ligand cyhxn (cyhxn?=?trans-cyclohexane-1,2-diamine) with Cu(OTf)2 in methanol at room temperature. The complex was fully characterized by elemental analysis (CHN), FT-IR, UV–Vis and EPR spectroscopic techniques. The structure of the complex was confirmed by single crystal X-ray diffraction study. The EPR spectrum is isotropic type having giso?=?2.078, which indicates a distorted octahedral geometry of the complex. The complex was found to be an active homogeneous catalyst for the homocoupling reactions of arylboronic acid to obtain symmetrical biaryls at room temperature in methanol without the use of any additives such as a base and or an oxidant.
- Agrahari, Bhumika,Layek, Samaresh,Kumari, Shweta,Anuradha,Ganguly, Rakesh,Pathak, Devendra D.
-
-
- With the catalytic 4 - tert-butyl-benzene boronic acid oxygen ether double-triazole copper complex and its preparation method
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The invention discloses a preparation method of [Cu(L)2(NO3) 2] (1) (L=1-(4-(4-(1H-1,2,4-triazole-1-methyl) phenoxy) phenyl)-1H-1,2,4-triazole) and potential application value as catalyst for a 4- tert-butylphenylboronic acid coupling reaction. A normal temperature evaporation method is employed that Cu(NO3)2 and L react at ambient temperature under stirring volatilization condition to prepare the complex. The invention further discloses application of [Cu(L)2(NO3)2] (1) (L=1-(4-(4-(1H-1, 2, 4-triazole-1-methyl) phenoxy) phenyl)-1H-1,2,4-triazole) as catalyst for the 4-tert-butylphenylboronic acid coupling reaction.
- -
-
Paragraph 0046; 0047; 0048
(2017/08/25)
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- Bimetallic Au-Pd nanochain networks: Facile synthesis and promising application in biaryl synthesis
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A simple and facile method is described for the morphology-controlled synthesis of bimetallic Au-Pd alloyed nanochain networks (NNCs) that show high catalytic performance for the Ullmann intermolecular homocoupling of aromatic or alkyl halides (X = I, Br, Cl) in aqueous media and can be reused at least five times, which can also be applied to intramolecular homocoupling.
- Wang, Zheng-Jun,Wang, Xia,Lv, Jing-Jing,Feng, Jiu-Ju,Xu, Xinhua,Wang, Ai-Jun,Liang, Zhiwu
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p. 3894 - 3899
(2017/07/12)
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- Synthesis of dendrimer-type viologen and its use in Pd-mediated homocoupling of aryl halides
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Dendrimer-type viologen (V2+.D.) was prepared from mesitylene and 4.4′-bipyridyl. Electroreduction of V2+.D. gave the corresponding quinoid (V0.D.), which promoted Pd-catalyzed homocoupling of aryl bromides Ar-Br to give the corresponding biaryls Ar-Ar in moderate to good yields.
- Kuroboshi, Manabu,Kojima, Atsuki,Tanaka, Hideo
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p. 2132 - 2140
(2017/11/21)
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- Homocoupling of iodoarenes and bromoalkanes using photoredox gold catalysis: A light enabled Au(III) reductive elimination
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The formation of homocoupled alkane byproducts have been identified in the reduction of bromoalkanes via photoredox gold catalysis with dimeric Au(I) complexes. This prompted further investigation into the mechanism of formation of these byproducts and the diversity of C-X bonds amenable to this transformation. Examples were found when considering bromoalkanes while a wide variety of iodoarenes underwent this process in good to excellent yields. The light enabled homocoupling of iodoarenes made possible by photoredox gold catalysis is reported.
- Tran, Huy,McCallum, Terry,Morin, Mathieu,Barriault, Louis
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supporting information
p. 4308 - 4311
(2016/09/09)
-
- INDUSTRIAL METHOD FOR PRODUCTION OF 3,7-DI-TERT-BUTYL-S-(TRIFLUOROMETHYL)DIBENZOTHIOPHENIUM TRIFLUOROMETHANESULFONATE
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Provided is an industrial method comprising a one-pot reaction process and an easy isolation process for the production of 3, 7-di-tert-butyl-S-(trifluoromethyl)dibenzothiphenium trifluoromethanesulfonate of formula (I) which is a useful trifluoromethylating agent. The method also includes using starting materials recovered after trifluoromethylation.
- -
-
Paragraph 16
(2016/10/04)
-
- Evidence for Direct Transmetalation of AuIII-F with Boronic Acids
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The underlying reactivity of AuIII-F species with aryl boronic acids has been studied in detail taking advantage of four novel, stable difluoro-[(C^N)AuF2], arylmonofluoro-[(C^N)AuArF], and alkylmonofluoro-[(C^N)AuAlkF] gold(III) complexes, prepared and isolated in monomeric form. We provide the first experimental evidence for a direct AuIII-F/B transmetalation preceding the Csp2-Csp2 or Csp3-Csp2 bond formation.
- Kumar, Roopender,Linden, Anthony,Nevado, Cristina
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p. 13790 - 13793
(2016/11/06)
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- Indazolium halides as efficient ligands for Pd-catalyzed Suzuki–Miyaura cross-coupling of aryl bromides with arylboronic acids
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The indazolium halides containing various N-substituents have been conveniently prepared and applied in the palladium-catalyzed Suzuki–Miyaura cross-coupling reactions of aryl bromides with arylboronic acids at mild reaction conditions. The cross-coupling reaction provides the desired products in good to high yields. The ease of synthesis and the modularity, and the broad range of aryl bromides and arylboronic acids make this type of ligand attractive and promising for transition metal catalysis.
- Chen, Qian,Mao, Zhuqing,Guo, Fang,Liu, Xiaoshuang
-
supporting information
p. 3735 - 3738
(2016/07/26)
-
- Solvent-Induced Single Crystal-Single Crystal Transformation of an Interpenetrated Three-Dimensional Copper Triazole Catalytic Framework
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The 2-fold interpenetrated 3D framework 1 can be solvent-induced to noninterpenetrated framework 1′ in a reversible single crystal-single crystal transformation fashion. In addition, 1′ represents the first catalyst based on triazole to catalyze the aerobic homocoupling of various substituted arylboronic acids.
- Wang, Ying,Meng, Shan-Shan,Lin, Peng-Xiang,Xiao, Yi-Wei,Ma, Qing-Qing,Xie, Qiong,Chen, Yuan-Yuan,Zhao, Xiao-Jun,Chen, Jun
-
supporting information
p. 4069 - 4071
(2016/05/24)
-
- With catalytic 4-tert-butyl-benzene boronic acid triazole-perchloricacid copper complex and method of preparing the same (by machine translation)
-
The invention discloses a preparation method of {[Cu(L)] (ClO4).0.25H2O} (1) (L=4-(3-(4H-1, 2, 4-triazole-4-yl)phenyl)-4H-1, 2, 4-triazole). The complex is prepared by using a hydrothermal method comprising the step of reacting Cu(ClO4)2 and L under a 100-DEG C hydrothermal condition. The invention further discloses application of a copper complex, namely {[Cu(L)] (ClO4).0.25H2O} (1) (L=4-(3-(4H-1, 2, 4-triazole-4-yl)phenyl)-4H-1, 2, 4-triazole) as a catalyst for coupled reaction of 4-tert-butylphenylboronic acid.
- -
-
Paragraph 041; 0042
(2017/03/08)
-
- With catalytic 4-tert-butyl-benzene boronic acid triazole-four fluoboric acid copper complex and method of preparing the same
-
The invention relates to a triazole and copper fluoroborate complex with a 4-tert-butylphenylboronic acid catalysis effect and a preparation method of the triazole and copper fluoroborate complex, and discloses a preparation method of {[Cu(L)] (BF4)2.0.5H2O} (1) (L=4-(3-(4H-1, 2, 4-triazole-4-yl)phenyl)-4H-1, 2, 4-triazole) and a potential application value of {[Cu(L)] (BF4)2.0.5H2O} (1) (L=4-(3-(4H-1, 2, 4-triazole-4-yl)phenyl)-4H-1, 2, 4-triazole) for catalyzing coupled reaction of 4-tert-butylphenylboronic acid. The complex is prepared by using a hydrothermal method and is namely prepared from Cu(BF4)2 and L under a hydrothermal condition of 100 DEG C. The invention further discloses application of {[Cu(L)] (BF4)2.0.5H2O} (1) (L=4-(3-(4H-1, 2, 4-triazole-4-yl)phenyl)-4H-1, 2, 4-triazole) as a 4-tert-butylphenylboronic acid coupled reaction catalyst.
- -
-
Paragraph 0045-0046
(2017/03/28)
-
- Miyaura Borylation and One-Pot Two-Step Homocoupling of Aryl Chlorides and Bromides under Solvent-Free Conditions
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Solvent-free protocols for Miyaura borylation and the one-pot, two-step homocoupling of aryl halides are reported for the first time. Bis(dibenzylideneacetone)palladium(0) [Pd(dba)2] is an optimal source of palladium for Miyaura borylation, while for one-pot two-step homocoupling palladium(II) acetate [Pd(OAc)2] gives highest yields. Aryl bromides are coupled most efficiently using the DPEphos ligand. Chlorides are coupled using XPhos. The developed protocols are robust, versatile and easily reproducible on a large scale.
- Dzhevakov, Pavel B.,Topchiy, Maxim A.,Zharkova, Daria A.,Morozov, Oleg S.,Asachenko, Andrey F.,Nechaev, Mikhail S.
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p. 977 - 983
(2016/04/05)
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- Aryl Ketones as Single-Electron-Transfer Photoredox Catalysts in the Nickel-Catalyzed Homocoupling of Aryl Halides
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An intriguing photoredox system for the homocoupling of aryl halides is reported wherein thioxanthone catalyzes a single-electron transfer from an amine reductant to nickel.
- Masuda, Yusuke,Ishida, Naoki,Murakami, Masahiro
-
supporting information
p. 5822 - 5825
(2016/12/18)
-
- Tertiary butyl-containing spirobifluorene compound and preparation and application thereof
-
The invention relates to a tertiary butyl-containing spirobifluorene compound and preparation and application thereof. The material has the following general formula (I) shown in the description, wherein R is a structure shown in the description; -Ar shown in the description, wherein -Ar is selected from at least one of the following structural units or derivatives of the following structural units: shown in the description; in the above mentioned structural formulas, m and n are integers of 0 to 8, and R1, R2, R3 and R4 are hydrogen, or straight chains or branched chains or ring alkyl or oxyalkyl chains with 1 to 22 carbon atoms, and can be the same or different. Compared with the prior art, the tertiary butyl-containing spirobifluorene compound disclosed by the invention has the advantages that 4,4'-ditert-butyl-2-brominated biphenyl with low cost replaces 2-brominated biphenyl which is generally used in the conventional 9,9'-spirobifluorene preparation process and is high in cost, and the synthesis method has the characteristics of low cost, simple synthesis route, high yield, easiness in industrial production and the like; a spirobifluorene hole-transmission/electroluminescent material is high in hole-transmission performance and electroluminescent performance.
- -
-
Paragraph 0107; 0111; 0112; 0113
(2017/02/17)
-
- Lewis acid-base interactions between platinum(II) diaryl complexes and bis(perfluorophenyl)zinc: Strongly accelerated reductive elimination induced by a Z-type ligand
-
Z-type interactions between bis(perfluorophenyl)zinc and platinum(ii) diaryl complexes supported by 1,10-phenanthroline (phen), 2,2′-bipyridine (bpy), and bis(dimethylphosphino)ethane (dmpe) ligands are reported. In the solid state, the nature of the Pt-Zn interaction depends on the bidentate ligand; the phen-supported complex exhibits an unsupported Pt-Zn bond, while the dmpe derivative features additional bridging aryl interactions. A strongly accelerated rate of reductive elimination is observed for phen- and bpy-supported complexes, while aryl exchange between Pt and Zn is observed for the dmpe complex.
- Liberman-Martin, Allegra L.,Levine, Daniel S.,Ziegler, Micah S.,Bergman, Robert G.,Tilley, T. Don
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p. 7039 - 7042
(2016/06/09)
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- METHOD FOR PRODUCING MULTISUBSTITUTED BIPHENYL COMPOUND AND SOLID CATALYST TO BE USED THEREIN
-
A method for producing a multisubstituted biphenyl compound is represented by the following formula (2), including a step of coupling a substituted benzene compound represented by the following formula (1) in the presence of a solid catalyst with gold immobilized onto a support.
- -
-
Paragraph 0190
(2015/12/23)
-
- Three-coordinate copper(I) 2-hydroxy-1,10-phenanthroline dinuclear complex catalyzed homocoupling of arylboronic acids towards biphenyls under air condition
-
An efficient synthesis of biphenyls via three-coordinate planar dinuclear Cu2(ophen)2 complex catalyzed homocoupling of arylboronic acids under air condition and in the condition of alkali-free was demonstrated. Uniquely, this catalyst shows high selectivity towards biphenyls when the reaction was conducted in aqueous solution, which is significantly different from selectivity towards phenols in related Cu-catalysts. Utilization of environmentally friendly water as main solvent, reaction at room temperature and in the absence of base, cheapness, low loading and easy bulk preparation of catalyst make it potential in green synthesis of biphenyls.
- Wang, Yan-Hong,Xu, Mei-Chen,Liu, Jie,Zhang, Ling-Juan,Zhang, Xian-Ming
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p. 9598 - 9601
(2015/12/04)
-
- Imino-N-heterocyclic carbene palladium(ii) complex-catalyzed direct arylation of electron-deficient fluoroarenes with "on and off" chelating effect assistance
-
An imino-N-heterocyclic carbene palladium(II) complex with a bulky substituted group on the imino nitrogen was used to catalyze the direct arylation of electron-deficient fluoroarenes with aryl halides. A series of electron-poor substrates and aryl bromides could be coupled in good to excellent yields with satisfactory position selectivity (20 examples, up to 93%). These arylations could proceed at a relatively low temperature (80 °C, 20 examples, up to 95%) with mono-N-protected amino acid assistance. Some of them even gained higher yields than those at high temperature (110 °C). Otherwise, some aryl iodides can forge cross-coupling products in yields of nearly 30% under the optimized conditions. The rate profiles for arylation of electron-poor arenes were measured in the presence of the imino-N-heterocyclic carbene palladium(II) complex or Pd(OAc)2 as the catalyst, which showed that the former could keep catalytic activity for a longer time. Computational studies indicated that the imino nitrogen in the imino-N-heterocyclic carbene ligand can detach from and attach to the central metal in the catalytic cycle. Thus, the coordination site could be protected, and this effect may be responsible for decreasing the rate of palladium black formation.
- Zhou, Quan,Wang, Ya-Nong,Guo, Xu-Qing,Zhu, Xiao-Han,Li, Zhi-Ming,Hou, Xiu-Feng
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p. 1021 - 1028
(2015/03/31)
-
- Ligand-, base-, co-catalyst-free copper fluorapatite (CuFAP) as a versatile, ecofriendly, heterogeneous and reusable catalyst for an efficient homocoupling of arylboronic acid at ambient reaction conditions
-
This paper describes the first report in which copper species containing copper fluorapatite (CuFAP) acts as a versatile, eco-friendly, recyclable, heterogeneous catalyst for an efficient synthesis of symmetric biaryls from the homo-coupling of arylboronic acids in methanol solvent at ambient reaction conditions. The developed protocol is ligand-, base-, and co-catalyst-free, sustainable, mild, inexpensive, and compatible with a wide range of aromatic/heterocyclic boronic acids and provides the corresponding products in excellent yields without purification. The catalyst was easily recovered from the reaction mixture and reused several times without loss of activity.
- Mulla, Shafeek A. R.,Chavan, Santosh S.,Pathan, Mohsinkhan Y.,Inamdar, Suleman M.,Shaikh, Taufeekaslam M. Y.
-
p. 24675 - 24680
(2015/03/30)
-
- In water homocoupling of arylboronic acids using nano-rod shaped and reusable copper oxide(II) catalyst at room temperature
-
The work describes a simple in situ soft chemical synthesis of rod shaped nano CuO, characterization and study of its catalytic performance in the aerobic homocoupling of arylboronic acids to synthesize symmetrical biphenyls. The catalyst is simple to prepare, environmentally benign, efficient, easy recovery, reusable, stable and heterogeneous in nature.
- Raul, Prasanta Kumar,Mahanta, Abhijit,Bora, Utpal,Thakur, Ashim Jyoti,Veer, Vijay
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p. 7069 - 7073
(2015/12/01)
-
