13490-70-5Relevant academic research and scientific papers
Hydration Reactivity of Persistent Conjugated Ketenes
Allen, Annette D.,Stevenson, Andrew,Tidwell, Thomas T.
, p. 2843 - 2848 (1989)
The acid, neutral, and base hydrations of the crowded alkenylketene 1 and the arylketenes i-PrCPh=C=O (2) and t-BuCPh=C=O (3) have been measured, together with solvent isotope effects and general acid catalysis of the hydration of 1.The arylketenes 2 and 3 are the first for which acid-catalyzed hydration has been demonstrated.These ketenes show significantly lower reactivity than simple ketenes, and this is interpreted as the result of both steric and electronic factors operating in mechanisms involving rate-limiting proton transfer to carbon (the γ-carbon in 1) for the acid-catalyzed reaction, while both the neutral and hydroxide-induced reactions involve rate-limiting nucleophilic attack in the plane of the ketene on the carbonyl carbon.
Iron-Catalyzed Asymmetric Decarboxylative Azidation
Wang, Kaikai,Li, Yajun,Li, Xiaoyan,Li, Daliang,Bao, Hongli
, p. 8847 - 8851 (2021/11/24)
The first iron-catalyzed asymmetric azidation of benzylic peresters has been reported with trimethylsilyl azide (TMSN3) as the azido source. Hydrocarbon radicals that lack of strong interactions were capable to be enantioselectively azidated. The reaction features good functional group tolerance, high yields, and mild conditions. The chiral benzylic azides can further be used in click reaction, phosphoramidation, and reductive amination, which demonstrate the synthetic values of this reaction.
Meta, para and ortho double exo nucleophilic additions of trimethylsilylester enolates derived from saturated and unsaturated carboxylic acids to tricarbonylchromium complexes of aryl ethers: dearomatizing cyclization to lactones
Rudler, Henri,Comte, Virginie,Garrier, Eva,Bellassoued, Moncef,Chelain, Evelyne,Vaissermann, Jaqueline
, p. 284 - 298 (2007/10/03)
Potassium enolates derived from saturated and unsaturated bis(trimethylsilyl) ketene acetals react with tricarbonylchromium complexes of anisole and diphenylether to give, in addition to α-arylcarboxylic acids, the mono addutcts, lactones, arising from a double exo nucleophilic addition. The latter were not observed in the case of benzenetricarbonylchromium. The intermediate dienol ethers could be isolated and fully characterized by X-ray crystallography. The influenece of the nature of the substituents on the ketene acetals, of the nature of the oxidant, and of the nature of the ester enolates on the course of the reaction has been established and will be discussed.
Generation of nitroalkanes, hydroximoyl halides and nitrile oxides from the reactions of β-nitrostyrenes with Grignard or organolithium reagents
Yao, Ching-Fa,Kao, Kuo-Hsi,Liu, Ju-Tsung,Chu, Cheng-Ming,Wang, Yeh,Chen, Wen-Chang,Lin, Yu-Mei,Lin, Wen-Wei,Yan, Ming-Chung,Liu, Jing-Yuan,Chuang, Ming-Ching,Shiue, Jin-Lien
, p. 791 - 822 (2007/10/03)
The β-nitrostyrenes 1 or 2 react with Grignard or organolithium reagents in ether or THF solution to generate by 1,4-addition the intermediate nitronates A. When A is treated with dilute hydrochloric acid, high yields of the nitroalkanes 3 (and oximes 4) or 5 are obtained Hydroximoyl halides 6, 8 or nitrile oxides 7 can be isolated when the intermediate A is slowly added to the ice cold concentrated hydrohalic acid. The same products 6 and/or 7 are observed if the nitronates, generated from the substrate 1a, are added to 85% aqueous H2SO4 but only the hydrolyzed carboxylic acids 9 are generated when the β-nitrostyrenes 2 are reacted with Grignard reagents and worked up under the same condition. The nitrile oxides 7 can undergo 1,3-dipolar cycloaddition with alkenes or alkynes to generate 2-isoxazolines or isoxazoles. A one-pot synthesis of the [n,3,0] bicyclic (n = 3 or 4) compounds 23-27 by intramolecular nitrile oxide-olefin cycloadditions is reported.
Reactions of β-nitrostyrenes with Grignard reagents
Yao, Ching-Fa,Chen, Wen-Chang,Lin, Yu-Mei
, p. 6339 - 6342 (2007/10/03)
α-Phenyl-β-nitrostyrene 1a and β-nitrostyrene 1b react with Grignard reagents to generate hydroxyimoyl halides 3 or nitrile oxides 4 after workup with ice cold concentrated aqueous HX acid solution. Carboxylic acids 5 are the only products isolated from 1b and products 3 or 4 are still obtained from 1a when concentrated sulfuric acid solution is used.
Dramatic Reversal of Diastereoselectivity in an N-Acyliminium Ion Cyclization Leading to Hexahydropyrroloisoquinolines. A Case of Competing Steric Interactions
Maryanoff, Bruce E.,McComsey, David F.,Almond, Harold R.,Mutter, Martin S.,Bemis, Guy W.,et al.
, p. 1341 - 1346 (2007/10/02)
The N-acyliminium ion cyclization 1 -> 2 + 3 (eq 1) with various aliphatic substituents (R = ethyl, cyclohexyl, and tert-butyl) was carried out, as an extension of our work in ref 2.The following 2:3 ratios were obtained: 39:61, 12:88, and 15:85, respecti
