- Fluorometric analysis of chlorite via oxidation of 9-anthracenecarboxaldehyde
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We investigated a simple fluorescence signaling method for the convenient analysis of a practical oxidant—chlorite—via the oxidation of 9-anthracenecarboxaldehyde to the corresponding carboxylic acid. 9-Anthracenecarboxaldehyde exhibited a marked ratiometric fluorescence signaling toward chlorite through manipulating its aggregation-induced emission property. The probe showed high chlorite-selectivity over other oxychlorine species as well as common metal ions, anions, and oxidants. Interference from a closely related oxidant, hypochlorite, was efficiently removed using DMSO as a scavenger. The proposed probe also exhibited a prominent ratiometric response through changes in UV–vis absorption behavior. Among the tested aromatic aldehydes (naphthaldehydes, anthracenecarboxaldehyde, and pyrenecarboxaldehyde), anthracene-based carboxaldehyde exhibited the most pronounced signaling contrast and the fastest signaling speed. The detection limit of chlorite determination was found to be 1.1 × 10–7 M. Exploitation of the probe for the convenient analysis of chlorite in tap water via a recovery test was conducted.
- Lee, Kang Min,Choi, Myung Gil,Yoo, Jae Hoon,Ahn, Sangdoo,Chang, Suk-Kyu
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- Fluorescence enhancement effect for the determination of adenosine 5′-monophosphate with 9-anthracene carboxylic acid-cetyl trimethyl ammonium bromide system
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A fluorimetric method based on fluorescence enhancement effect was developed for the determination of adenosine 5′-monophosphate (AMP) with 9-anthracene carboxylic acid (9-ANCA)-cetyl trimethyl ammonium bromide (CTAB) system. Fluorescence intensity of 9-ANCA was decreased by the addition of CTAB but addition of AMP again rose the intensity of 9-ANCA gradually. The observed fluorescence enhancement is attributed to the competitive binding reaction of 9-ANCA and adenosine to CTAB. The enhancement in the fluorescence intensity was found proportional to the concentration of AMP over the range 2.0∈×∈10-4 to 1.2∈×∈10-3 mol dm-3. The ion pair complex is formed spontaneously between 9-ANCA and CTAB. Since the binding interaction is larger for the adenosine-CTAB pair, the fluorophore 9-ANCA will be released. The quantum yield of free 9-ANCA is higher therefore its fluorescence observed at 417 nm wavelength is enhanced. This mechanism of competitive molecular interaction is further confirmed by conductometric measurements. The method was applied successfully for the determination of AMP from pharmaceutical sample. The method is more selective, sensitive and relatively free from interferences.
- Khot, Mahadev S.,Desai, Netaji K.,Kolekar, Govind B.,Patil, Shivajirao R.
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- 4-Biphenylaldehyde and 9-anthraldehyde: Two fluorescent substrates for determining P450 enzyme activities in rat and human
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1. 4-Biphenylaldehyde (4-BA) and 9-anthraldehyde (9-AA) were examined as substrates for cytochrome P450 (CYPs) enzymes in rat and human. Both aldehydes were oxidized by CYPs to fluorescent carboxylic acids, which can be assayed with a high sensitivity by an easy fluorimetric method. 2. With liver microsomes from control and induced rats, the oxidation of both 9-AA and 4-BA followed simple Michaelis-Menten kinetics. Only microsomes from rats pretreated with phenobarbital (a strong inducer of P4502B1/2) could increase (about threefold) the oxidation rates (Vmax) of both aldehydes above the control values, which were 6.7 ± 1.1 and 3.3 ± 0.6 nmolmin-1 mg-1 protein for 4-BA and 9-AA, respectively. On the other hand, the Km's, which were similar for both aldehydes (about 25 μM), did not change significantly with any inducer. The use of purified rat CYP1A1, 2E1, 2B1 and 2C11 in a reconstituted system showed that only 2B1 and 2C11 could oxidize both substrates with a high turnover. 3. In human liver microsomes, the oxidation rates of these aldehydes (1.6 ± 0.2 and 0.42 ± 0.1 nmolmin-1 mg-1 protein for 4-BA and 9-AA, respectively) were lower than those of rat but with similar Km's (20-26 μM). 4. The oxidation of these aldehydes was also determined with cDNA-expressed CYP1A1, 1A2, 2A6, 2B6, 2C9, 2D6, 2E1 and 3A4 and with a characterized bank of 14 human liver microsomes. In a reconstituted system, only CYP2B6, 2A6, 3A4 and with a lower turnover 2C9 oxidized both substrates. 5. Among the CYP marker activities of the 14 human samples, good correlations were only observed between CYP3A-dependent 6β-testosterone hydroxylase and the oxidation of 4-BA (r = 0.74) or 9-AA (r = 0.80) and between the oxidation of 4-BA versus 9-AA (r = 0.74). Weak correlations were also found between the 2B6-linked S-mephenytoin Ndemethylase and the oxidation of 4-BA (r = 0.58) or 9-AA (r = 0.65). 6. Inhibition experiments revealed that the oxidation of these aldehydes was inhibited by ketoconazole, 8-methoxypsoralene and sulphophenazole, selective inhibitors for P4503A6, 2A6 and 2C9, respectively. 7. In summary, based on the use of cDNA-expressed CYPs, correlation analysis and chemical inhibition, the metabolism in human liver microsomes of these aldehydes appears primarily catalysed by CYP3A, although CYP2A6, 2B6 and 2C9 may play a role. 9-AA and particularly 4-BA, owing to the high rate of its metabolism, may be two novel useful fluorescent probe substrates for assaying CYP activities in various species.
- Marini,Grasso,Longo,Puccini,Riccardi,Gervasi, P. Giovanni
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- On-Demand Degradation of Metal-Organic Framework Based on Photocleavable Dianthracene-Based Ligand
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We have designed a rigid photocleavable dianthracene-based ligand that reacts with ytterbium as coordination metal ion for the creation of a class of tridimensional light-degradable metal-organic framework (MOF). We demonstrated that we can obtain a high level of control on the disassembly of the MOF formed with this ligand which can be triggered either through light irradiation or temperature increase. The reversible 4π-4π photodimerization is the intrinsic chemical mechanism ruling the ligand and MOF cleavage. In the fields of biology and medicine, MOFs have sparked a strong interest as highly porous vehicles for drug release but have only been explored so far through the passive leakage of their payloads. The designed light-degradable MOFs can potentially overcome this limitation and serve as prototypes for drug delivery and corresponding therapeutic applications.
- Collet, Guillaume,Lathion, Timothée,Besnard, Céline,Piguet, Claude,Petoud, Stéphane
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- Surface active ionic liquid assisted metal-free electrocatalytic-carboxylation in aqueous phase: A sustainable approach for CO2utilization paired with electro-detoxification of halocarbons
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Electrocarboxylation of halocarbons is a promising green synthetic strategy for capture, fixation and utilization of CO2 for the synthesis of high-added-value industrial compounds. However, the unparalleled kinetic/thermodynamic stability and solubility concerns of CO2 and halocarbons warrant the use of appropriate (often precious metal based) electrocatalytic electrodes and environmentally non-green solvent systems to drive this otherwise kinetically slow electrochemical process. Herein we demonstrate that owing to their unique solubility and excellent electrocatalytic properties, the aqueous micellar solutions of imidazolium-based surface active ionic liquids (SAILs) can be used for the efficient and selective electrocatalytic-carboxylation of halocarbons to produce carboxylic acids. Specifically, we present results from our detailed electrochemical investigations regarding the electroreductive cleavage of the C-X bond and electrocarboxylation of 9-bromoanthracene (9-BAN) and chloroacetonitrile (CAN) in buffered (pH 7, phosphate buffer) micellar solutions of 1-dodecyl-3-methyl-imidazolium chloride ([DDMIM][Cl]). We demonstrate that the unique ability of [DDMIM][Cl] micelles to stabilize the electrogenerated reactive intermediates facilitates a novel reaction pathway that ensures selective and efficient electrocatalytic-reductive carboxylation of 9-BAN and CAN. The presented results clearly establish that besides allowing for the electrocarboxylation of halocarbons in aqueous green electrolytes, the use of SAILs ensures electrochemical fixation of CO2 at practically low cost current and potential conditions imposed over metal free, economically viable and electrochemically robust carbon electrodes. The use of SAILs is reported to improve the faradaic efficiency (~95%) and reduce the chances of undesired side product reactions which continue to be a major concern in the state of art electro-carboxylation processes. The presented approach we opine offers a promising avenue toward design of eco-green pathways in the direction of CO2 fixation and electro-organic synthesis of a diverse range of value-added products from water insoluble halocarbons (toxic pollutants) in aqueous media.
- Bhat, Khursheed Ahmad,Bhat, Mohsin Ahmad,Bhat, Sajad Ahmad,Ingole, Pravin P.,Manzoor Bhat, Zahid,Pandit, Sarwar Ahmad,Rather, Mudasir Ahmad,Rehman, Shakeel U.,Sofi, Feroz Ahmad,Thotiyl, Musthafa Ottakam
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p. 9992 - 10005
(2021/12/24)
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- Synthesis method of 9-anthracenecarboxylic acid
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The present invention relates to the field of synthesis technology of dye intermediates and electronic fluorescent materials, providing a new synthesis method of 9-anthracenecarboxylic acid, comprising the following steps: 9- anthracenecarboxaldehyde as raw material, reacting under the action of oxidants and auxiliaries and pH buffers, after the completion of the reaction, the solvent is evaporated, the pH = 1-5, the organic matter is extracted, and then the organic phase is evaporated, which can be prepared to give 9-anthracenecarboxylic acid. The present invention solves the prior art synthesis of 9- anthracenecarboxy acid by-products more, low yield and other issues, synthesis of 9- anthracene formaldehyde as raw material, under the action of oxidants and auxiliaries and pH buffers for reaction, the prepared yellow solid for nuclear magnetic hydrogen spectrometry identification and liquid chromatography detection, the results show that the prepared product structure is 9-anthracic acid, purity up to 99% or more, thus illustrating that the synthesis method of the present invention is less by-product, easy to purify, mild reaction conditions, simple operation, stable product quality, Suitable for industrial production.
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Paragraph 0031; 0032; 0036-0041
(2022/01/07)
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- Method for copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide
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The invention discloses a method for a copper-catalyzed carboxylation reaction of arylboronic acid and carbon dioxide. According to the method, carbon dioxide is used as a C1 source, copper catalysisis adopted, alkoxide serves as alkali, and a reaction is carried out in an organic solvent; the method is simple in process and easy to implement, and shows wide functional group compatibility; the method allows various arylboronic acids such as monosubstituted or polysubstituted phenylboronic acid, polycyclic aromatic hydrocarbon boronic acid and benzoheterocyclic boronic acid to be converted into corresponding arylcarboxylic acids with considerable yield under mild conditions; and the produced carboxylic acids have important application value, and can be used for deriving a great number of other common chemical substances, such as acyl halide, acid anhydride, ester and amide.
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Paragraph 0095; 0096
(2019/12/29)
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- Efficient aerobic photooxygenation of aldehydes to carboxylic acids using cobalt(II) phthalocyanine sulfonate as a photosensitizer in organic-water biphasic media
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The aerobic oxidation of a variety of aromatic aldehydes to the corresponding carboxylic acids by molecular oxygen in the presence of 4-carboxyl tetraphenylporphyrin (H2TCPP), methylene blue (MB), cobalt(II) phthalocyanine sulfonate (CoPcS) and FeTCPPCl as water-soluble photosensitizers in organic-water biphasic media at room temperature under either visible light or sunlight is described. The products were obtained with 25–100% conversion and 100% selectivity. This method has a wide range of applicabilities, has a straightforward workup procedure, is chemoselective and proceeds under mild reaction conditions. The resulting products were obtained in good yields in reasonable times.
- Hajimohammadi, Mahdi,Ahmadi Khamesi, Zahra,Nosrati, Parisa
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p. 167 - 173
(2018/10/31)
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- Synthesis and transformations of a few 9-(pent-4-yn-1-yl)anthracene-type systems
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9-(Pent-4-yn-1-yl)anthracene-type compounds can potentially undergo intramolecular Diels-Alder (IMDA) reaction to form 9,11-annulated dibenzobarrelenes. Herein we report the synthesis and IMDA reactions of several heteroatom incorporated 9-(pent-4-yn-1-yl)anthracene-type compounds.
- Mathew, Eason M.,Devassia, Tomson,Prathapan, Sreedharan,Unnikrishnan, Perupparampil A.
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- A Highly Efficient NHC-Catalyzed Aerobic Oxidation of Aldehydes to Carboxylic Acids
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An N-heterocyclic carbene (NHC) organocatalytic aerobic oxidation of aldehydes to the corresponding carboxylic acids is explored. Remarkably, this method allows for efficient conversion of different classes of aldehydes including highly challenging electron-rich aryl aldehydes, ortho -substituted aryl aldehydes, various heteroaromatic aldehydes and α,β-unsaturated aldehydes under mild reaction conditions. These substrates, under previously reported NHC-catalyzed methods, are typically unreactive or give poor yields, require high reaction temperatures and reaction times of several days.
- Khatana, Anil Kumar,Singh, Vikram,Gupta, Manoj Kumar,Tiwari, Bhoopendra
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p. 4290 - 4294
(2018/11/23)
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- Chemical reaction method for growing photomechanical organic microcrystals
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(E)-3-(Anthracen-9-yl)acrylic acid (9-AYAA) exhibits a strong photomechanical response in bulk crystals but is challenging to grow in microcrystalline form. High quality microcrystals of this molecule could not be grown using techniques like sublimation, reprecipitation, and the floating drop method. If the tertbutyl ester of 9-AYAA is used as a starting material, however, high quality, size-uniform microwires could be grown via acid catalyzed hydrolysis. 9-AYAA microwires with uniform length and thickness were produced after a suspension of (E)-tert-butyl 3-(anthracen-9-yl)acrylate ester microparticles was tumble-mixed in a mixture of phosphoric acid and sodium dodecyl sulfate at 35°C. The dependence of the results on temperature, surfactant and precursor concentration, and mixing mode was investigated. This chemical reaction-growth method was extended to grow microplates of 9-anthraldehyde using the corresponding acylal as the starting material. Under 475 nm irradiation, the 9-AYAA microwires undergo a photoinduced coiling-uncoiling transition, while the 9-anthraldehyde microplates undergo a folding-unfolding transition.
- Al-Kaysi, Rabih O.,Zhu, Lingyan,Al-Haidar, Maram,Al-Muhannah, Muhannah K.,El-Boubbou, Kheireddine,Hamdan, Tarafah M.,Bardeen, Christopher J.
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p. 8835 - 8842
(2015/11/27)
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- NOVEL ISOXAZOLINES AND THEIR USE IN CONTROLLING PESTS
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Disclosed herein are novel isoxazoline compounds of the general formula (I), compositions comprising these novel compounds, and uses of these compounds in the control of pests in both animal health and plant protection contexts. The compounds can be combined with other biologically active materials such as organophosphate pesticides, carbamate -type pesticides, organochlorine type pesticides, pyrethrins/pyrethroids, neonicotinoids, avermectins, milbemycins, benzimidazoles, salicylanilides, substituted phenols, pyrimidines, tetrahydropyrimidines, imidazothiazoles, amino/amido acetonitrile derivatives, febantel, clorsulon, levamisole, morantel, and praziquantel, juvenile hormone mimics and chitin synthesis inhibitors. (I)
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Paragraph 00123; 00128
(2015/11/02)
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- Direct conversion of aromatic aldehydes into benzamides via oxidation with potassium permanganate in liquid ammonia
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Oxidation of aromatic aldehydes by KMnO4 in liquid ammonia gives amides directly. The reaction proceeds satisfactorily when the aldehydes are activated by electron-withdrawing substituents on the ring.
- Antoniak, Damian,Sakowicz, Arkadiusz,Loska, Rafa?,Makosza, Mieczys?aw
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supporting information
p. 84 - 86
(2015/02/05)
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- Copper-catalyzed synthesis of aromatic carboxylic acids from arylboronic acids and acetyl acetate
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A simple and efficient copper-catalyzed method for the synthesis of aromatic carboxylic acids in moderate to high yields with great functional-group compatibility in the substrates has been developed. The new method uses readily available arylboronic acids and acetyl acetate as the starting materials and inexpensive CuI as the catalyst.
- Zheng, Rui,Zhou, Qizhong,Gu, Haining,Jiang, Huajiang,Wu, Jiashou,Jin, Zhengneng,Han, Deman,Dai, Guoliang,Chen, Rener
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supporting information
p. 5671 - 5675
(2014/12/11)
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- A mild oxidation of deactivated naphthalenes and anthracenes to corresponding para-quinones by N-bromosuccinimide
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A new method to synthesize 1,4-naphthoquinone and 9,10-anthraquinone from naphthalene and anthracene functionalized with either -CHO or -COOH groups, using N-bromosuccinimide (NBS) in aqueous N,N-dimethylformamide at 75-80 °C, has been developed. Further, -CN and -CONH2 functionalized naphthalenes and anthracenes can also be transformed into respective para-quinones in a one pot reaction, after successive acid hydrolysis and subsequent reaction with NBS. We believe that the present finding may serve as a valuable alternative to the classical approaches for the synthesis of polycyclic quinones from polyaromatic carbaldehydes through Dakin oxidation followed by further oxidation of the resulting hydroquinone by heavy metal oxides.
- Natarajan, Palani,Vagicherla, Vinuta Devi,Vijayan, Muthana Thevar
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p. 3511 - 3515
(2014/06/10)
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- Electrophilic aromatic substitution of arenes with CO2 mediated by R3SiB(C6F5)4
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The FriedelCrafts- type carboxylation of arenes has been achieved by activating CO2 with silylium borates. The reaction exhibits broader substrate applicability than does our previously reported AlX3/R 3SiX-mediated carboxylation.
- Konno, Megumi,Chiba, Masafumi,Nemoto, Koji,Hattori, Tetsutaro
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p. 913 - 914,2
(2020/08/31)
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- Polyvinylpyrrolidone-supported hydroperoxide for selective oxidation of aldehydes to carboxylic acids and sulfides to sulfoxides
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The facile immobilization of hydroperoxide on the cross-linked poly(vinylpyrrolidone) is described by treatment of a poly(vinylpyrrolidone)- Vilsmeier adduct with (35%) hydrogen peroxide. The in situ-generated poly(vinyl pyrrolidone)-supported hydroperoxide reagent showed very good performance in chemoselective oxidation of aldehydes to carboxylic acids as well as sulfides to sulfoxides. Supplemental materials are available for this article. Go to the publishers online edition of Phosphorus, Sulfur, and Silicon and the Related Elements to view the free supplemental file. Taylor & Francis Group, LLC.
- Lakouraj, Moslem Mansour,Aghajani, Bahareh,Mokhtary, Masoud
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experimental part
p. 2393 - 2401
(2011/03/17)
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- Design of protonated polyazamacrocycles based on phenanthroline motifs for selective uptake of aromatic carboxylate anions and herbicides
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Three novel large polyazamacrocycles containing two 1,10-phenanthroline (phen) units connected by two polyamine spacers of different length, [32]phen2N4, [30]phen2N6 and Me 2[34]phen2N6, have been synthesised and their protonated forms used as receptors for binding studies with several aromatic carboxylate anions (benzoate (bzc-), 1-naphthalate (naphc -), 9-anthracenate (anthc-), pyrene-1-carboxyl-ate (pyrc-), phthalate, (ph2-), isophthalate (iph 2-), terephthalate (tph2-), 2,5-dihydroxy-1,4- benzenediacetate (dihyac2-) and, 1,3,5-benzenetricarboxylate (btc3-)) and three herbicides (4-amino-3,5,6-trichloropyridine-2- carbox-ylate (ATCP-), dichlorophenoxyacetate (2,4-D-) and glyphosate (PMG2-)) in water solution. The [30]phen2N 6 receptor was found to be the most suitable for binding the anions considered in a 1:1 stoichiometry. The three receptors exhibit a remarkable binding selectivity towards the extended aromatic anion pyre- at low pH values. Their binding affinities for the monocarboxylate anions decrease with the extension of the aromatic system in the order pyre- > anthc- > naphc- > bzc-, which indicates the presence of π-π stacking interactions in the molecular recognition of these anions. Molecular dynamics simulations carried out for the binding of (H4[30]phen2N6}4+ and {H 6Me2[34]phen2N6}6+ with pyre-, anthc-, naphc-, iph2- and btc3- in water showed that these receptors adopt a folded conformation with the anion inserted between the two phen heads and that the molecular recognition is governed by π-π stacking interactions and multiple N-H...O=C hydrogen bonds. The binding free energies estimated theoretically are very similar to those found by Potentiometric methods, which supports the proposed binding arrangement.
- Cruz, Carla,Cahsto, Vania,Delgado, Rita,Felix, Vitor
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supporting information; scheme or table
p. 3277 - 3289
(2009/12/05)
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- Lewis acid-mediated carboxylation of fused aromatic compounds with carbon dioxide
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Direct and regioselective carboxylation of fused aromatic compounds with carbon dioxide is achieved with the aid of a Lewis acid. Thus, treatment of naphthalene, anthracene, and phenanthrene with carbon dioxide (3.0 MPa) in benzene at 40 °C in the presenc
- Suzuki, Yutaka,Hattori, Tetsutaro,Okuzawa, Tomohiro,Miyano, Sotaro
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p. 102 - 103
(2007/10/03)
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- Mechanism for photocleavage of N-(anthroyloxy)-9-fluorenylideneamines and dynamic behavior of anthroyloxyl radicals
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Photocleavage of the N-O bond of N-(9-anthroyloxy)-9-fluorenylideneamine and its 1-and 2-anthroyloxy derivatives takes place efficiently in acetonitrile in the excited singlet state attributed to the fluorenylidene moiety. This made it possible for the first time to directly observe anthroyloxyl radicals by the transient absorption method. The quantum efficiency for photocleavage decreases remarkably in benzene, in which the lowest excited singlet state is attributed to the anthroate moiety. All the three kinds of anthroyloxyl radicals are much less reactive in decarboxylation, addition to olefins, and hydrogen-atom abstraction than benzoyloxyl and 1- and 2-naphthoyloxyl radicals; 9-anthroyloxyl radicals supposedly undergo intramolecular addition-elimination in the ipso-position in equilibrium with α-lactonic spirodihydroanthryl radicals, as indicated by one-color and two-color laser photolyses.
- Saitoh, Yasuo,Kaneko, Makoto,Segawa, Katsunori,Itoh, Hiroki,Sakuragi, Hirochika
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p. 2013 - 2023
(2007/10/03)
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- Solvent and excitation wavelength effects on photocleavage of N-(9-anthroyloxy)-9-fluorenylideneamine as a precursor of 9-anthroyloxyl radicals. A mechanistic study
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Photocleavage of the N-O bond of N-(9-anthroyloxy)-9-fluorenylideneamine takes place efficiently in acetonitrile in the excited singlet state attributed to the fluorenylidene moiety. This made it possible for the first time to directly observe 9-anthroyloxyl radicals. However, the efficiency decreases remarkably in benzene in which the lowest excited singlet state is attributed to the anthroate moiety. (C) 2000 Elsevier Science Ltd.
- Saitoh,Segawa,Itoh,Sakuragi
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p. 8353 - 8357
(2007/10/03)
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- Effect of substituent character on carbonylation of aryl halides in two-phase systems
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Effect of substituent character in the ring of aryl bromides on their reactivity in carbonylation resulting in aromatic acids. The reaction was carried out in two-phase system p-xylene - water in the presence of palladium-phosphinic catalysts. Optimal conditions of preparation of arylcarboxylic acids were developed.
- Lapidus,Petrovskii,Bruk,Beletskaya
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p. 1636 - 1639
(2007/10/03)
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- The Chemiluminescent Cycloreversion of an Anthracene-Benzene Biplanemer System both in the Solid State and in the Liquid State
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In the thermal cycloreversions of 9-anthracenecarboxylic acid-benzene 3a, methyl 9-anthracenecarboxylate-benzene 3b, dimethyl (or diethyl) 9,10-anthracenedicarboxylate-benzene 3c (or 3d) and anthracene-1,4-difluoro(or dichloro)benzene 3f (or 3g) biplanemers, chemiluminescence was observed for 3a-d only in the solid state at > 120 deg C but not in a liquid phase, while 3f and 3g were not chemiluminescent.Efficient chemiluminescence was observed in the photocycloreversion of all biplanemers tested in both phases.The thermodynamic parameters for the thermal cycloreversion of these biplanemers were collected.Higher activation energies were obtained in the solid state than in the liquid phase.The higher energies favor touch of the S0 surface with the S1 surface at the transition state for effecting the chemiluminescent cycloreversion.
- Kimura, Masaru,Okamoto, Hideki,Kashino, Setsuo
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p. 2203 - 2212
(2007/10/02)
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- Manganese(III)-Mediated Formylation of Aromatic Compounds in the Presence of Malonic Acid
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The reaction of naphthlenes with malonic acid in the presence of manganese(III) acetate gives naphthalenecarbaldehydes and naphthalenecarboxylic acids.Similar reactions of anthracene, pyrene, and methoxybenzenes also yield formylated and carboxylated products.It was found that the formyl group introduced to the aromatic ring was not derived from carboxymethyl radical generated directly by the thermolysis of manganese(III) acetate, but from a dicarboxymethyl radical formed by the interaction of malonic acid and manganese(III) acetate.In addition, it was also found that the dicarboxymethyl radicals attacked the position of the highest electron density on the aromatic ring and that this formylation was effective when the ionization potential of the aromatic copound was lower than 7.8 eV.
- Nishino, Hiroshi,Tsunoda, Katsunori,Kurosawa, Kazu
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p. 545 - 550
(2007/10/02)
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- The Baeyer-Villiger Reaction of Polycyclic Aromatic Aldehydes: Preparation of Polycyclic Phenols
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Baeyer-Villiger reactions of such polycyclic aromatic aldehydes as 2-dibenzofurancarbaldehyde with various peroxy compounds have been studied in detail, giving predominantly the corresponding phenols.
- Fujishiro, Koichi,Mitamura, Shuichi
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p. 4464 - 4466
(2007/10/02)
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- Synthesis and Properties of Dinitromethylated Arenes. Reinvestigation of the Ponzio Reaction
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Several title compounds have been prepared by the modified Ponzio procedure and their IR, 1 H and 13 C NMR data are presented.In some cases trinitromethylated arenes were obtained as a by-product.Oxidative cleavage to parent aldehydes and oxidation to carboxylic acids were the major competing reactions. 9-Anthracenecarbaldehyde oxime and 10-methyl-9-anthracenecarbaldehyde oxime reacted with nitrogen dioxide in an unexpected way, giving 10-nitro-9-anthracenecarbonitrile oxide and 10-methyl-10-nitro-9-anthrone as the respective main products.Nitration of (dinitromethyl)benzene has also been examined under various conditions.
- Suzuku, Hitomi,Takaoka, Hiroshi,Yamamoto, Hidetoshi,Ogawa, Takuji
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p. 2927 - 2932
(2007/10/02)
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- Regioselective Metallation of Aromatic Compounds, II. Second Metallation of 1-Lithionaphthalene and 9-Lithioanthracene
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Both 1-lithionaphthalene (2) and 9-lithioanthracene (12) undergo specific metallations whereby a second lithium is introduced at the adjacent peri-positions (5, 18) (in the presence of n-butyllithium/N,N,N',N'-tetramethylenediamine (TMEDA)).Explanations for such directed second metallations, for which other examples are known, are provided by MNDO calculations.Not only are the dilithiated products stabilized by symmetrically double bridging (implying a thermodynamic driving force) but also the activated hydrogens in the monolithio precursors are indicated clearly.The LUMO-coefficients on these hydrogens are largest and the C-H bond lenghts longest.Dimers, more realistic models for the solution species, show these characteristics as well.
- Neugebauer, Wolfgang,Clark, Timothy,Schleyer, Paul von Rague
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p. 3283 - 3292
(2007/10/02)
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