- Selective hydrogenation of 3,3-dimethylbutanoyl chloride to 3,3-dimethylbutyraldehyde with silica supported Pd nanoparticle catalyst
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A novel method for selective hydrogenation of 3,3-dimethylbutanoyl chloride (DMBC) to 3,3-dimethylbutyraldehyde (DMBA) with silica supported Pd nanoparticle catalyst (Pd/SiO2) is developed. The catalysts were characterized by Fourier transform infrared spectroscopy, X-ray powder diffraction, N2 physisorption and transmission electron microscopy. The performance of the Pd/SiO2 catalyst was compared with Pd/C and Pd/BaSO4 catalysts with or without being pretreated by quinoline-sulfur. The Pd/SiO2 catalyst activated at 80 °C by bubbling hydrogen in cyclohexane for 1 h showed the highest yield of DMBA. For 3 wt.% Pd/SiO2, the yield of DMBA reached 84.6%, which exhibited much higher value than Pd/C and Pd/BaSO4 catalysts.
- Li, Sifang,Chen, Guoqin,Sun, Lan
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Read Online
- A convenient synthesis of 3,3-dimethylbutyraldehyde
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3,3-Dimethylbutyraldehyde is synthesized from the reaction of 1-chloro-3,3-dimethylbutane with DMSO in presence of a base and substoichiometric amounts of MX (M = Na, K; X = Br, I).
- Guo,Sawyer,Prakash
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Read Online
- A convenient synthesis of 3,3-dimethylbutyraldehyde
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3,3-Dimethylbutyraldehyde is synthesized from the reaction of 1-chloro-3,3-dimethylbutane with DMSO in presence of a base and substoichiometric amounts of MX (M=Na, K; X=Br, I).
- Guo,Sawyer,Prakash
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Read Online
- Production process 3 and 3 - dimethyl butyraldehyde
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The invention belongs to the technical field of chemical synthesis and particularly relates to a production technology of 3,3-dimethylbutyraldehyde. The production technology sequentially comprises the following steps: S1, taking tert-butyl alcohol and ethylene as raw materials, taking n-hexane as a reaction solvent, and catalyzing by using sulfuric acid to synthesize 3,3-dimethyl butyl sulfate; S2, under the action of the catalyst, controlling the temperature to be 30 to 50 DEG C and hydrolyzing to obtain 3,3-dimethylbutanol; S3, performing catalyzed oxidation on the 3,3-dimethylbutanol by using an inhibitor 701 and dimethylethyl nitrite to obtain the 3,3-dimethylbutyraldehyde. The production technology has the advantages of safety, reliability, low cost, good reproducibility and high purity of a final product.
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Paragraph 0031; 0035-0036; 0039-0040; 0043
(2020/11/13)
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- The formyloxyl radical: Electrophilicity, C-H bond activation and anti-Markovnikov selectivity in the oxidation of aliphatic alkenes
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In the past the formyloxyl radical, HC(O)O, had only been rarely experimentally observed, and those studies were theoretical-spectroscopic in the context of electronic structure. The absence of a convenient method for the preparation of the formyloxyl radical has precluded investigations into its reactivity towards organic substrates. Very recently, we discovered that HC(O)O is formed in the anodic electrochemical oxidation of formic acid/lithium formate. Using a [CoIIIW12O40]5- polyanion catalyst, this led to the formation of phenyl formate from benzene. Here, we present our studies into the reactivity of electrochemically in situ generated HC(O)O with organic substrates. Reactions with benzene and a selection of substituted derivatives showed that HC(O)O is mildly electrophilic according to both experimentally and computationally derived Hammett linear free energy relationships. The reactions of HC(O)O with terminal alkenes significantly favor anti-Markovnikov oxidations yielding the corresponding aldehyde as the major product as well as further oxidation products. Analysis of plausible reaction pathways using 1-hexene as a representative substrate favored the likelihood of hydrogen abstraction from the allylic C-H bond forming a hexallyl radical followed by strongly preferred further attack of a second HC(O)O radical at the C1 position. Further oxidation products are surmised to be mostly a result of two consecutive addition reactions of HC(O)O to the CC double bond. An outer-sphere electron transfer between the formyloxyl radical donor and the [CoIIIW12O40]5- polyanion acceptor forming a donor-acceptor [D+-A-] complex is proposed to induce the observed anti-Markovnikov selectivity. Finally, the overall reactivity of HC(O)O towards hydrogen abstraction was evaluated using additional substrates. Alkanes were only slightly reactive, while the reactions of alkylarenes showed that aromatic substitution on the ring competes with C-H bond activation at the benzylic position. C-H bonds with bond dissociation energies (BDE) ≤ 85 kcal mol-1 are easily attacked by HC(O)O and reactivity appears to be significant for C-H bonds with a BDE of up to 90 kcal mol-1. In summary, this research identifies the reactivity of HC(O)O towards radical electrophilic substitution of arenes, anti-Markovnikov type oxidation of terminal alkenes, and indirectly defines the activity of HC(O)O towards C-H bond activation.
- Iron, Mark A.,Khenkin, Alexander M.,Neumann, Ronny,Somekh, Miriam
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p. 11584 - 11591
(2020/11/23)
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- Synthesis technology used for preparing 3, 3-dimethylbutyraldehyde through micro-channel reaction
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The invention belongs to the technical field of organic synthesis, and more specifically relates to synthesis technology used for preparing 3, 3-dimethylbutyraldehyde through micro-channel reaction. According to the synthesis technology, reaction is carried out in two micro-channel reactors connected in series; in a first micro-channel reactor, chloro-tert-butane and vinyl acetate are taken a raw materials, aluminium trichloride-dichloromethane system is taken as a catalyst to perform synthesis reaction, a reaction product is introduced into a second micro-channel reactor for mixing with OR water for hydrolysis reaction, an obtained hydrolysis product is subjected to extraction separation so as to obtain a 3, 3-dimethylbutyraldehyde crude product, and rectification is adopted to prepare the pure 3, 3-dimethylbutyraldehyde. The synthesis technology is scientific and reasonable; reaction condition accurate control is realized; synthesis is simple and convenient; production cost is low; purity is 99.5% or higher; the synthesis process is friendly to the environment; and the purity is high.
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Paragraph 0039-0046
(2019/10/10)
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- 3, 3-dimethybutyraldehyde synthesizing process with metal catalysts
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The invention relates to a 3, 3-dimethybutyraldehyde synthesizing process with metal catalysts and belongs to the technical field of organic synthesis. The 3, 3-dimethybutyraldehyde synthesizing process with the metal catalysts comprises the following steps of, firstly, cooling down dichloromethane solvent through a liquid nitrogen cooling device; secondly, sequentially uniformly mixing and dissolving in 2-chloro-2-methylpropane and the metal catalysts; thirdly, adding in vinyl acetate into the mixed solution of the second step to obtain a crude reaction product; fourthly, distilling the crudereaction product; fifthly adding in ice tubes into the distillate of the fourth step; lastly, adding sodium carbonate into the distillate of the fifth step and performing secondary distillation to obtain pure 3, 3-dimethybutyraldehyde. The 3, 3-dimethybutyraldehyde synthesizing process with the metal catalysts is scientific, reasonable and easy to implement and has the advantages of being low inproduction cost, high in yield, green, environmentally friendly and high in purity.
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Paragraph 0030-0035
(2019/04/06)
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- Preparation method for key intermediate of neotame--3,3-dimethylbutyraldehyde
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The invention provides a preparation method for key intermediate of neotame--3,3-dimethylbutyraldehyde, comprising the following steps: under nitrogen protection in a vessel, organic solvent and a solid acid catalyst are added, tert-butyl chloride and aryl acid vinyl esters are dropped; through a thermal insulation reaction, the catalyst is filtered, the organic layer is decompressed and distilled, and alkali or acid is added for heating, backflow and hydrolysis to produce a crude product to be rectified to produce the final 3,3-dimethylbutyraldehyde product. The preparation method for the keyintermediate of neotame--3,3-dimethylbutyraldehyde has the advantages of low material cost and simple operation, moderate reaction conditions and less side reactions and is safe, environmentally friendly and beneficial for industrial production.
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Paragraph 0030-0031
(2018/12/02)
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- Method for synthesizing 3,3-dimethyl butyraldehyde
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The invention provides a technological method for synthesizing 3,3-dimethyl butyraldehyde. The technological method comprises the following steps: adding an organic solvent and a solid acid catalyst into a container under the protection of nitrogen gas; dropwise adding tert-butyl chloride; then dropwise adding alkyl acid type vinyl ester; carrying out heat-insulation reaction, then filtering to remove a catalyst; then decompressing and distilling an organic layer; then adding alkali or acid, and heating, refluxing and hydrolyzing to obtain a crude product; then rectifying the crude product toobtain a 3,3-dimethyl butyraldehyde finished product. The technological method has the advantages of low raw material cost, mild reaction conditions, simplicity in operation and few side reaction, safety and environmental protection, and industrialized production is facilitated.
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Paragraph 0025-0028
(2018/12/03)
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- Promotion effect of nickel for Cu–Ni/γ-Al2O3 catalysts in the transfer dehydrogenation of primary aliphatic alcohols
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Cu–Ni/γ-Al2O3 bimetallic catalysts were developed for anaerobic dehydrogenation of non-activated primary aliphatic alcohols to aldehydes. Systematic investigation about the promotion effect of nickel on the catalytic performance was carried out. Hydrogenation of C=C bond rather than C=O bond, was significantly improved over Cu–Ni/γ-Al2O3 catalyst by introducing nickel, which interprets the good conversion of primary aliphatic alcohols. This work would contribute to design new catalysts for dehydrogenation of primary aliphatic alcohols.
- Yang, Xiaomei,Fu, Xiaomin,Bu, Ningning,Han, Li,Wang, Jianfeng,Song, Chengying,Su, Yunlai,Zhou, Lipeng,Lu, Tianliang
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p. 111 - 119
(2017/01/05)
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- SeO2-Mediated One-Pot Synthesis of 3-Cyanofurans from 3-Oxo-3-arylpropanenitriles and Substituted Acetaldehydes
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An SeO2-mediated one-pot method was established for the synthesis of 3-cyanofurans from 3-oxo-3-arylpropanenitriles and substituted acetaldehydes. The generality of the reaction was explored, and a plausible mechanism is proposed.
- Zhou, Jie,Zhu, Xinhai,Huang, Manna,Wan, Yiqian
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supporting information
p. 2317 - 2321
(2017/05/01)
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- A catalytic oxidation of 3,3-dimethyl-1-butanol prepare 3,3-dimethyl-1-butanal method of
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A method for catalytically oxidizing 3,3-dimethyl-1-butanol to prepare 3,3-dimethyl1-butyraldehyde is disclosed. The method comprises taking dioxygen as an oxidant, taking azaadamantane type nitroxide free radical (or a derivative thereof) and nitric acid (or a nitrite) as catalysts, and under the condition of 30-120 DEG C, high selectively oxidizing 3,3-dimethyl-1-butanol into 3,3-dimethyl1-butyraldehyde. The method has the characteristics of high oxidation efficiency, mild reaction conditions, no metals in product, small environmental pollution and the like, and has important application value.
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Paragraph 0022; 0023
(2016/10/07)
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- A 1-chloro -3,3-dimethyl butyl acetate hydrolysis method of the
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The invention belongs to the technical field of chemical engineering, and particularly relates to a hydrolysis method for 1-chlorine-3,3-dimethylbutyl acetate. The hydrolysis method for 1-chlorine-3,3-dimethylbutyl acetate comprises the following steps: 1-chlorine-3,3-dimethylbutyl acetate is added into an alcohol and water mixed solution slowly and are heated to have an action, the reaction temperature is 20-60 DEG C, the reaction time lasts for 2-4 hours, the temperature is raised for rectification after the reaction, and fractions at the temperature of 99-102 DEG C are collected to obtain 3,3-dimethyl butyraldehyde. The water and methyl alcohol mixed solution serves as a solvent, so 1-chlorine-3,3-dimethylbutyl acetate can be better mixed with the solvent, catalysts do not need to be added, hydrolysis is conducted under a mild condition, high-temperature polymerization by-products are avoided to a large extent, methyl alcohol can be recycled and repeatedly used, the cost is further reduced, discharged waste water and waste gas are reduced, the environmental protection pressure is further reduced, and the method is easy to conduct and suitable for industrial production.
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Paragraph 0029; 0030
(2017/03/08)
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- Dehydrogenation of primary aliphatic alcohols to aldehydes over Cu-Ni bimetallic catalysts
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The catalytic conversion of non-activated primary aliphatic alcohols to aldehydes is a challenge, and monometallic Cu-based catalysts loaded on different supports have often been used for these reactions. Cu-Ni/γ-Al2O3 bimetallic catalysts were prepared and used for anaerobic dehydrogenation of 3,3-dimethyl-1-butanol to 3,3-dimethyl-1-butanal. These catalysts exhibited higher activity than Cu/γ-Al2O3 under the same reaction conditions, and a wide range of primary aliphatic alcohols were efficiently converted to the corresponding aldehydes over Cu-Ni/γ-Al2O3 under mild conditions.
- Lu, Tianliang,Du, Zhongtian,Liu, Junxia,Chen, Chen,Xu, Jie
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p. 1911 - 1916
(2015/09/28)
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- Broad-spectrum catalysts for the ambient temperature anti-Markovnikov hydration of alkynes
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Anti-Markovnikov alkyne hydration provides a valuable route to aldehydes. Half-sandwich ruthenium complexes ligated by 5,5′-bis(trifluoromethyl)-2, 2′-bipyridine are remarkably active for this transformation. In the presence of 2 mol % metal, a wide range of functionalized aliphatic and aromatic alkynes are hydrated in high yield at ambient temperature. Alkyne hydration: Half-sandwich ruthenium complexes derived from 5,5′-bis(trifluoromethyl)- 2,2′-bipyridine show a high activity for the anti-Markovnikov hydration of terminal alkynes (see picture). A wide array of alkynes are efficiently hydrated to aldehydes using 2 mol % metal loadings at 25 °C within 8-24 h.
- Li, Le,Zeng, Mingshuo,Herzon, Seth B.
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supporting information
p. 7892 - 7895
(2014/08/05)
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- METHOD FOR PREPARING 3,3-DIMETHYLBUTYRALDEHYDE
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A method for preparing 3,3-dimethylbutyraldehyde. The method includes: providing t-butyl chloride and vinyl acetate as raw materials, conducting a catalytic reaction between the t-butyl chloride and vinyl acetate to yield 1-chloro-3,3-dimethyl butyl acetate in the presence of a catalyst, the weight ratio of t-butyl chloride to vinyl acetate being 1: 0.84-0.93; and controlling a temperature at between 100 and 110° C. for conducting hydrolytic disproportionation of 1-chloro-3,3-dimethyl butyl acetate in the presence of the catalyst to yield a mixture comprising 3,3-dimethylbutyraldehyde; and purifying the mixture by distillation to yield 3,3-dimethylbutyraldehyde, in which, the catalyst is aluminum trichloride, p-toluene sulphonic acid, or iron trichloride.
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Paragraph 0024
(2014/05/07)
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- PREPARATION METHOD FOR 3,3-DIMETHYL BUTYRALDEHYDE
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A method for preparing 3,3-dimethylbutyraldehyde. The method includes: providing t-butyl chloride and vinyl acetate as raw materials, conducting a catalytic reaction between the t-butyl chloride and vinyl acetate to yield 1-chloro-3,3-dimethyl butyl acetate in the presence of a catalyst, the weight ratio of t-butyl chloride to vinyl acetate being 1: 0.84-0.93; and controlling a temperature at between 100 and 110°C for conducting hydrolytic disproportionation of 1-chloro-3,3-dimethyl butyl acetate in the presence of the catalyst to yield a mixture comprising 3,3-dimethylbutyraldehyde; and purifying the mixture by distillation to yield 3,3-dimethylbutyraldehyde, in which, the catalyst is aluminum trichloride, p-toluene sulphonic acid, or iron trichloride.
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Paragraph 0011
(2014/06/24)
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- Steric effects and mechanism in the formation of hemi-acetals from aliphatic aldehydes
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Some physical properties (pKa, log POW, boiling points) of hexanoic acid 1 (X = COOH) and its seven isomers 2, 3, 4, 5, 6, 7, 8 (X = COOH) are reported. Hexanal 1 (X = CHO) and its seven isomeric aldehydes 2, 3, 4, 5, 6, 7, 8 (X = CHO) are shown to equilibrate, in methanol solution, with their hemi-acetals. Logarithms of equilibrium constants correlate with values of Es for the isomeric C5H11 substituents, and with logs of relative rates for saponification of the corresponding methyl esters with ρ = 0.52, reflecting the reduced steric demand of hydrogen compared to oxygen in the quaternization of ester and aldehydic carbonyl groups. Rates of equilibration have also been measured in buffered methanol. For hexanal, with a 2:1 Et3N:AcOH buffer, the buffer-independent contribution is dominated by the methoxide catalysed pathway. Rates in this medium have been determined for isomers 1, 2, 3, 4, 5, 6, 7, 8 (X = CHO), and their logarithms do not correlate with logarithms of equilibrium constants for hemi-acetal formation or with substituent steric parameters derived from ester formation or saponification, indicating that the steric changes associated with full quaternization of the carbonyl group are not mirrored in the transition structures for hemi-acetal formation. It is suggested that transition states for hemi-acetal formation are relatively early so that steric interactions are effectively those between the nucleophile and ground state conformations of the aldehydes. A comparison of the entropies of hemi-acetal formation with entropies of activation has provided a basis for a suggested transition structure. Comparisons with acid chloride hydrolyses are made. Copyright 2013 John Wiley & Sons, Ltd. Logarithms of equilibrium constants for formation hemi-acetals of hexanal and its seven isomeric aldehydes correlate well with values of Es for the isomeric C5H11 substituents, and with logs of relative rates for saponification of the corresponding methyl esters. Logarithms of rate constants for hemi-acetal formation do not, indicating that the steric changes associated with full quaternization of the carbonyl group are not mirrored in the transition structures for hemi-acetal formation. The reasons for this are discussed. Copyright
- Daw, Graham,Regan, Andrew C.,Watt, C. Ian F.,Wood, Evan
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p. 1048 - 1057
(2014/01/06)
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- Manganese(III) acetate mediated oxidative radical cyclizations. Toward vicinal all-carbon quaternary stereocenters
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Manganese(III) acetate mediated oxidative radical cyclizations have been used to synthesize a range of densely functionalized and sterically congested cyclopentane-lactones. A number of the resulting lactones contain vicinal all-carbon quaternary stereocenters adjacent to a tertiary benzylic stereocenter and are formed with high levels of stereocontrol.
- Logan, Angus W.J.,Parker, Jeremy S.,Hallside, Michal S.,Burton, Jonathan W.
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supporting information; experimental part
p. 2940 - 2943
(2012/08/28)
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- A combined DFT and NMR investigation of the zinc organometallic intermediate proposed in the syn-selective tandem chain extension-aldol reaction of β-keto esters
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The tandem chain extension-aldol (TCA) reaction of β-keto esters provides an α-substituted γ-keto ester with an average syn:anti selectivity of 10:1. It is proposed that the reaction proceeds via a carbon-zinc bound organometallic intermediate potentially bearing mechanistic similarity to the Reformatsky reaction. Evidence, derived from control Reformatsky reactions and a study of the structure of the TCA intermediate utilizing DFT methods and NMR spectroscopy, suggests the γ-keto group of the TCA intermediate plays a significant role in diastereoselectivity observed in this reaction. Such coordination effects have design implications for future zinc mediated reactions.
- Aiken, Karelle S.,Eger, Wilhelm A.,Williams, Craig M.,Spencer, Carley M.,Zercher, Charles K.
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experimental part
p. 5942 - 5955
(2012/10/08)
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- Biooxidation of Primary Alcohols to Aldehydes through Hydrogen Transfer Employing Janibacter terrae
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Chemoselective oxidations still represent a challenge for chemists. Lyophilized cells of Janibacter terrae were employed for the chemoselective oxidation of primary alcohols to the corresponding aldehydes by hydrogen transfer with the use of acetaldehyde as the hydrogen acceptor. Secondary alcohol moieties were transformed at a much slower rate. The substrate spectrum encompasses substituted benzyl alcohols, whereby substrates with a substituent in the meta position were well tolerated, whereas only very small substituants were tolerated in the ortho position. Furthermore, nalkanols and allylic alcohols were transformed with good conversions. The biocatalyst was compatible with DMSO as a water miscible organic solvent up to 30 % v/v.
- Orbegozo, Thomas,De Vries, Johannes G.,Kroutil, Wolfgang
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experimental part
p. 3445 - 3448
(2010/09/05)
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- Kinetics and products of the reactions of oh radicals with 4,4-dimethyl-1-pentene and 3,3-dimethylbutanal at 296 ± 2 k
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Using a relative rate method, rate constants have been measured for the reactions of OH radicals with 4,4-dimethyl-1-pentene [(CH3) 3CCH2CH=CH2] and its major reaction product, 3,3-dimethylbutanal [(CH3)3CCH2CHO], at 296 ± 2 K and atmospheric pressure of air. The rate constants obtained were 2.41 × 10-11 and 2.73 × 10-11 cm3 molecule-1 s-1, respectively, with estimated uncertainties of ±10%. The products identified and quantified by gas chromatography with mass spectrometry and/or flame ionization detection from the 4,4-dimethyl-1-pentene reaction were acrolein [CH2=CHCHO], 3,3-dimethylbutanal, and a molecular weight 112 carbonyl attributed to 4,4-dimethyl-2-pentenal [(CH3)3CCH=CHCHO], with formation yields of 2.7 ± 0.5%, 59 ± 6%, and 3.4 ± 0.6%, respectively. Using direct air sampling atmospheric pressure ionization mass spectrometry, additional products of molecular weight 146, 177, and 193 were observed, and on the basis of expected reaction schemes these are attributed to the dihydroxycarbonyl HOCH2C(CH3)2CH 2C(O)CH2OH, the hydroxynitrates (CH3) 3CCH2CH(OH)CH2ONO2 and/or (CH 3)3CCH2CH(ONO2)CH2OH, and the dihydroxynitrate O2NOCH2C(CH3) 2CH2CH(OH)CH2OH, respectively. The hydroxynitrates were also tentatively identified by gas chromatography, with a summed yield of ~15%. Acrolein and 4,4-dimethyl-2-pentenal arise from H-atom abstraction from the three equivalent CH3 groups and the 3-position CH2 group, and the sum of their formation yields (6.1 ± 0.8%) is expected to be very close to the fraction of the overall reaction proceeding by H-atom abstraction.
- Aschmann, Sara M.,Arey, Janet,Atkinson, Roger
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experimental part
p. 5810 - 5816
(2010/09/06)
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- PYRRO[1,2-B]PYRIDAZINONE COMPOUNDS
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The invention is directed to pyrro[l,2-b]pyridazinone compounds and pharmaceutical compositions containing such compounds that are useful in treating infections by hepatitis C virus.
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Page/Page column 74-75
(2008/06/13)
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- CATALYST SYSTEM FOR AEOROBIC OXIDATION OF PRIMARY AND SECONDARY ALCOHOLS.
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The present invention relates to a process of oxidation of alcohols selectively to aldehydes or ketones with molecular oxygen using a TEMPO based catalyst, Fe-bipyridyl or Fe-phenantroline co-catalyst and N- bromosuccinimide promoter in acetic acid solvent. The oxidation takes places at high rates and high aldehyde selectivity at temperatures in the range 45-50°C and oxygen or air pressures of 0-15psi. The alcohol conversion of 95-100% and aldehyde selectivity higher than 95% are achieved over 3-4 hours reaction time. Aldehydes such as 3,3-dimethyl-l-butanal can be produced efficiently using the present invention.
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Page/Page column 11-12
(2008/06/13)
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- Bromine free TEMPO based catalyst system for oxidation of primary and secondary alcohols using NaOCl as an oxidant
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The present invention relates to a process of oxidation of alcohols selectively to aldehydes or ketones with NaOCl using a TEMPO—borate catalyst system. It is shown that the oxidation can be efficiently carried out without KBr additives under solvent free conditions. Aldehydes such as 3,3-dimethylbutyraldehyde can be produced efficiently using the present invention.
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Page column 11
(2008/06/13)
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- BROMINE FREE TEMPO BASED CATALYST SYSTEM FOR OXIDATION OF PRIMARY AND SECONDARY ALCOHOLS USING NAOCI AS AN OXIDANT.
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The present invention relates to a process of oxidation of alcohols selectively to aldehydes or ketones with NaOCI using a TEMPO - borate catalyst system. It is shown that the oxidation can be efficiently carried out without KBr additives under solvent free conditions. Aldehydes such as 3,3-dimethylbutyraldehyde can be produced efficiently using the present invention.
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- Synthesis of 3,3,-dimethylbutyraldehyde by the reduction of 3,3,-dimethylbutyric acid
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A process for the production of 3,3-dimethylbutyraldehyde is disclosed. The 3,3-dimethylbutyraldehyde is obtained by the reduction of 3,3-dimethylbutyric acid using trimethylacetic anhydride and a phosphine. The 3,3-dimethylbutyric acid is preferably obtained by a process in which tert-butanol and vinylidene chloride are reacted in the presence of sulfuric acid. The disclosed process has improved cost and yield.
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- Process for the preparation of 3,3-dimethylbutanal
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3,3-Dimethylbutanal is prepared from 3,3-dimethylbutanol. Intermediate 3,3-dimethylbutanol is obtained by reacting ethylene, isopropylene and sulfuric acid to produce a 3,3-dimethylbutyl ester which is hydrolyzed to the alcohol. The hvdrolysis step is effectively carried out by reactive distillation. Alternatively, 3,3-dimethylbutanal is prepared from 3,3-dimethylbutanol obtained by reduction of the corresponding carboxylic acid or 1,2-epoxy-3,3-dimethylbutane, or by hydrolysis of 1-halo-3,3-dimethylbutane. Fixed bed gas phase and stirred tank liquid phase processes are provided for converting 3,3-dimethylbutanol to 3,3-dimethylbutanal by catalytic dehydrogenation.
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- Preparation of 3,3-dimethylbutyraldehyde by oxidation of 3,3-dimethylbutanol
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This invention provides a method for preparing 3,3-dimethylbutyraldehyde comprising the step of contacting 3,3-dimethylbutanol with an oxidizing metal oxide for a time and at a temperature sufficient for said metal oxide to oxidize 3,3-dimethylbutanol to form said 3,3-dimethylbutyraldehyde. The method of this invention provides a commercially practicable means of preparing 3,3-dimethylbutyraldehyde.
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Page column 3
(2008/06/13)
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- Method for hydrogenating carbonyl compounds
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A process for the catalytic hydrogenation of a carbonyl compound or of a mixture of two or more carbonyl compounds in the presence of a catalyst which comprises an inorganic support containing TiO2, and as active component copper or a mixture of copper and at least one of the metals selected from the group of zinc, aluminum, cerium, a noble metal and a group VIII metal, wherein the copper surface area does not exceed 10 m2/g.
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- Combined effects of metal and ligand capable of accepting a proton or hydrogen bond catalyze anti-Markovnikov hydration of terminal alkynes
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A binding pocket for water is created in 1 by the imidazolyl phosphane ligands and the Ru11 center. Compound 1 proves to be an excellent catalyst for a highly selective anti-Markovnikov hydration of terminal alkynes to give aldehydes rather than isomeric ketones under near-neutral conditions (aldehyde-to-ketone ratio up to 1000:1).
- Grotjahn, Douglas B.,Incarvito, Christopher D.,Rheingold, Arnold L.
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p. 3884 - 3887
(2007/10/03)
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- Ruthenium complex-catalyzed anti-Markovnikov hydration of terminal alkynes
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Highly regioselective, efficient, and substituent-tolerant anti-Markovnikov hydration of terminal alkynes occurs to give n-aldehyde by use of a catalytic amount of easily available cyclopentadienylruthenium complexes bearing appropriate bidentate or monodentate phosphme ligands. Typically, RuCpCl(dppm) (1 mol %) catalyzes the addition of water to 1-hexyne at 100°C to give hexanal in 95% yield: 2-hexanone is not detected at all.
- Suzuki, Toshiaki,Tokunaga, Makoto,Wakatsuki, Yasuo
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p. 735 - 736
(2007/10/03)
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- Intramolecular functionalisation by a methylene radical of a 1,2-diol and a vicinal amino alcohol: Models for coenzyme B12-dependent diol dehydratase and ethanolamine ammonia lyase
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Coenzyme B12-dependent diol dehydratase converts 1,2-diols (e.g. propane-1,2-diol) into the corresponding aldehyde and water. The similar enzyme ethanolamine ammonia lyase transforms vicinal aminoalcohols (e.g. 2-aminoethanol) into the corresponding aldehyde and ammonia. Model systems have been developed that replicate key features of the putative enzymatic mechanism, i.e. removal of a hydrogen atom from the CH2OH group of a 1,2-diol or vicinal aminoalcohol by a methylene radical derived from an alkylcobalt compound, and conversion of a 1,2-diol or vicinal aminoalcohol into a carbonyl compound and water or ammonia triggered by such a methylene radical. The models are based on alkyl(pyridine)bis(dimethylglyoximato)cobalt complexes [alkyl(pyridine)cobaloximes, Cbx], which were synthesised from appropriate organic precursors using standard methodology. The complexes contain a 1,2-diol [as in 4,5-dihydroxy-2,2-dimethylpentyl(pyridine)cobaloxime] or vicinal aminoalcohol [as in 6-amino-5-hydroxy-2,2-dimethylhexyl(pyridine)cobaloxime] tethered to the cobalt by a carbon chain. Photolysis or thermolysis of 4,5-dihydroxy-2,2-dimethylpentyl(pyridine)cobaloxime at pH 3 or 9 gave 4,4-dimethylpentanal. It is proposed that homolysis of the Co-C bond of 4,5-dihydroxy-2,2-dimethylpentyl(pyridine)cobaloxime induced by photolysis or thermolysis affords the 1,2-dihydroxy-4,4-dimethyl-l-pentyl radical via a 1,5-H shift, which is converted into the 4,4-dimethyl-1-oxo-2-pentyl radical, and hence 4,4-dimethylpentanal. The pathway for formation of the aldehyde was diagnosed using the specifically deuteriated analogue [5,5-2H 2]-4,5-dihydroxy-2,2-dimethylpentyl(pyridine)-cobaloxime, which gave [1,5-2H2]-4,4-dimethylpentanal accompanied by 3,3-dimethylbutanal on thermolysis or photolysis at pH 3. The protected model compound 2a was hydrolysed to 6-amino-5-hydroxy-2,2-dimethylhexyl(pyridine)cobaloxime, which was heated at pH 3 or 9 to give 5,5-dimethylhexan-2-one and ammonia. The Royal Society of Chemistry 2000.
- Andersen, Rosaleen J.,Ashwell, Susan,Garnett, Ian,Golding, Bernard T.
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p. 4488 - 4498
(2007/10/03)
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- A novel preparation of 3,3-dimethylbutyraldehyde via isomerization of 3,3-dimethyl-1-butene epoxide
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3,3-Dimethylbutyraldehyde is prepared in a highly economical manner by regioselective isomerization of the title epoxide in the presence of LiTMP.
- Katritzky, Alan R.,Fang, Yunfeng,Prakash, Indra
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p. 635 - 636
(2007/10/03)
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- α-(Acyloxy)dialkylnitrosamines: Effects of structure on the formation of N-nitrosiminium ions and a predicted change in mechanism
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The decay of α-(acyloxy)dialkylnitrosamines in aqueous solutions has been studied with a view toward elucidating mechanistic details and effects of structure on mechanism and reactivity. Rate constants (k1) for the pH-independent decay of 43 α-(acyloxy)dialkylnitrosamines have been determined. Observations from these and other experiments rule out decomposition via an anchimeric assistance mechanism involving the Z isomer that had previously been suggested. All of the reported data for most of the compounds is consistent with a mechanism involving the formation of N-nitrosiminium ions in or before the rate-limiting step. Structure -reactivity correlations indicate that the stability of α-(acyloxy)dialkylnitrosamines is determined by electronic properties of substituents at RN and RC as well as by the ability of substituents RC to engage in hyperconjugative interactions of C-H bonds with the developing cationic center in the transition state for nitrosiminium ion formation. Attachment of substituents of sufficient electron-withdrawing power at RN and RC results in a predicted change in mechanism to what appears to be an acyl group attack mechanism.
- Hongliang, Cai,Fishbein, James C.
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p. 1826 - 1833
(2007/10/03)
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- Synthesis and purification of 3,3-dimethylbutyraldehyde via hydrolysis of 1,1-dichloro-3,3-dimethylbutane or 1-bromo-1-chloro-3,3-dimethylbutane
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3,3-Dimethylbutyraldehyde is synthesized via hydrolysis of 1,1-dichloro-3,3-dimethylbutane or 1-bromo-1-chloro-3,3-dimethylbutane in the presence of water and a base and is purified via an aldehyde/bisulfite adduct.
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- Preparation of 3,3-dimethylbutyraldehyde by oxidation of 3, 3-dimethylbutanol
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This invention provides a method for preparing 3,3-dimethylbutyraldehyde from 3,3-dimethylbutanol using an oxidizing component. In one embodiment, 3,3-dimethylbutanol is oxidized to 3,3-dimethylbutyraldehyde in the vapor phase by contacting it with an oxidizing metal oxide compound. In another embodiment, the oxidation of 3,3-dimethylbutanol is carried out by treating it with 2,2,6,6-tetramethyl-1-piperidinyloxy, free radical and an oxidizing agent in a solvent to produce 3,3-dimethylbutyraldehyde. The method of this invention provides a commercially practicable means of preparing 3,3-dimethylbutyraldehyde.
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- Synthesis and purification of 3,3-dimethylbutyraldehyde via oxidation of 1-chloro-3,3-dimethylbutane with dimethyl sulfoxide
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1-chloro-3,3-dimethylbutane is oxidized by dimethyl sulfoxide, in the presence of an effective amount of inorganic bromide or iodide, and in the present of an effective amount of base, to produce 3,3-dimethylbutyraldehyde.
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- 1,4-DIHYDROPYRIDINE DERIVATIVES
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A 1,4-dihydropyridine derivative having the formula (I): wherein, R1represents a substituted or unsubstituted phenyl or heterocyclic group, R2represents a C1to C5lower alkyl group, R3represents a substituted or unsubstituted C2to C8alkyl, alkenyl, alkynyl or substituted or unsubstituted cycloalkyl group, R4represents -A-R5, wherein A represents a C2to C8alkylene group or a substituted or unsubstituted C2to C8alkenylene group, and R5represents a substituted or unsubstituted pyridyl, pyridylcarbonyl or piperadinyl group and a drug for overcoming resistance to an anti-cancer drug or a drug increasing the effect of an anti-cancer drug containing as an effective ingredient the derivative or its pharmacologically acceptable salt or hydrate.
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- Method for preparing and purifying an N-alkylated aspartame derivative
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A method is disclosed for preparing and purifying N-?N-(3,3-dimethylbutyl)-L-α-aspartyl!-L-phenylalanine 1-methyl ester from aspartame and 3,3-dimethylbutyraldehyde by hydrogenation in an organic solvent solution followed by the formation of an aqueous/organic solvent solution having an organic solvent content of about 17% to about 30% by weight of the aqueous/organic solvent solution.
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- Zirconium-mediated Ring Opening of Cyclopropanes
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Zirconocene η2-alkene and η2-imine complexes with adjacent cyclopropane rings undergo cyclopropane ring cleavage to afford novel η3-allyl, η3-azaallyl, and η1-enamine complexes.
- Dimmock, Paul W.,Whitby, Richard J.
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p. 2323 - 2324
(2007/10/02)
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- DEHYDROGENATION OF SUBSTITUTED ALCOHOLS TO ALDEHYDES ON ZINC OXIDE-CHROMIUM OXIDE CATALYSTS
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Sixteen primary alcohols of the structure RCH2OH (R = CH3, C2H5, (CH3)2CH, (CH3)3CCH2, HOCH2, CH3OCH2, C6H5, C6H5CH2, C6H5OCH2, ClCH2, BrCH2, F3C, CNCH2, (CH3)2NCH2, (C2H5)2NCH2 and tetrahydrofurfuryl) were explored for the possibility of obtaining the corresponding aldehydes by dehydrogenation on solid catalysts.Various catalysts were tested and two zinc oxide-chromium oxide catalysts were selected for further work because their activity and selectivity was satisfactory; moreover, the selectivity could be improved by addition of sodium into the catalysts and of water into the feed.The reaction was performed in the temperature range 250 - 450 deg C and at atmospheric pressure. 2-Chloroethanol, 2-bromoethanol, ethylene glycol, 2-cyanoethanol and 2-(N,N-diethylamino)ethanol decomposed and deactivated the catalyst.The other alcohols were studied from the point of kinetics of dehydrogenation, which was described by a Langmuir-Hinshelwood type rate equation (3), and of substituent effects on rate, which were correlated by Taft equation (1) with the slope ρ* = -1.46.The preparative value of catalytic dehydrogenation for obtaining substituted aldehydes was confirmed by prolonged runs and isolation of the aldehydic product by distillation using as the feeds 2-methoxyethanol and 2-(N,N-dimethylamino)ethanol, respectively.
- Gulkova, Daniela,Kraus, Milos
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p. 2215 - 2226
(2007/10/02)
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- 7-oxabicycloheptyl substituted heterocyclic amide or ester prostaglandin analogs useful in the treatment of thrombotic and vasospastic disease
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7-Oxabicycloheptane substituted prostaglandin analogs useful in treating thrombotic and vasopastic disease have the structural formula STR1 wherein m is 1, 2 or 3; n is 1, 2, 3 or 4; Z is --(CH2)2 --, --CH=CH-- or STR2 wherein Y is O, a single bond or vinyl, with the proviso that when n is 0, if Z is STR3 then Y cannot be O, and Z is --CH=CH--, n is 1, 2, 3 or 4; and when Y=vinyl, n=0; R is CO2 H, CO2 lower alkyl, CH2 OH, CO2 alkali metal, CONHSOR3, CONHR3a or --CH2 --5-tetrazolyl, X is O, S or NH; and where R1, R2, R3 and R3a are as defined herein.
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- Acceleration of the 4-exo radical cyclization to a synthetically useful rate. Cyclization of the 2,2-dimethyl-5-cyano-4-pentenyl radical
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The title radical, formed in the reaction of the corresponding bromide with Bu3SnH, cyclizes in a 4-exo fashion to give the (3,3-dimethylcyclobutyl)cyanomethyl radical. At 50°C, the rate constant for cyclization is 1.9 x 104s-1.
- Park,Varick,Newcomb
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p. 2975 - 2978
(2007/10/02)
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- ORGANOMANGANESE (II) REAGENTS XVIII: COPPER-CATALYZED 1,4-ADDITION OF ORGANOMANGANESE CHLORIDE COMPOUNDS TO CONJUGATED ETHYLENIC ALDEHYDES.
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Organomanganese chlorides react with β-mono or β,β-bisubstituted α,β-ethylenic aldehydes in the presence of a catalytic amount of copper chloride to give good yields of 1,4-addition products in THF at -30 deg C.
- Cahiez, Gerard,Alami, Mouad
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p. 7365 - 7368
(2007/10/02)
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- Effect of Pressure on the Rate of Methylation of a Buttressed Pyridine
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3,5-Di-tert-butylpyridine (3) and 2,6-dimethyl-3,5-di-tert-butylpyridine (4) have been synthesized.Compound 3 was obtained by means of acid-catalyzed condensation of N-tert-butylmethanimine with N-(3,3-dimethylbut-1-enyl)piperidine; this reaction also furnished 3,5-di-neo-hexylpyridine (7).Compound 4 was prepared from Hantzsch's ester 8, by an application of the Schleyer method for converting ester groups into tert-butyl functions.The methylation rates of 3 and 4 in acetonitrile at 45 deg C were compared with those of pyridine and 2,6-lutidine.It was deduced that the two tert-butyl groups cause a retardation by buttressing by a factor of 57.Comparison with the known rates of 5- and 3-tert-butyl-2-methylpyridines (1 and 2, respectively) shows that the buttressing effect is minimized in the latter case by bending of the incipient N-methyl bond.The rates were also measured under pressure; the activation volumes follow the normal trend expected of directly hindered Menschutkin reactions.
- Cheung, C. K.,Wedinger, R. S.,Noble, W. J. le
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p. 570 - 573
(2007/10/02)
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- PEPTIDES CONTAINING A NEOPENTYLGLYCINE RESIDUE
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Neopentylglycine (III, 2-amino-4,4-dimethylpentanoic acid) was synthesized in both enantiomeric forms.Using the conventional methods of peptide synthesis, L-prolyl-L-neopentylglycylglycine amide (VII), the diastereomeric cyclodipeptides cyclo(L-neopentylglycyl-L-prolyl) (IXa) and cyclo(D-neopentylglycyl-L-prolyl) (IXb) and also N-acetyl-L-neopentylglycine methylamide (X) were prepared as models for further studies on physical properties and conformation of peptides.
- Pospisek, Jan,Blaha, Karel
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p. 514 - 521
(2007/10/02)
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