2432-50-0Relevant academic research and scientific papers
Hydrophobic Vitamin B12. V. Electrochemical Carbon-Skeleton Rearrangement as Catalyzed by Hydrophobic Vitamin B12: Reaction Mechanisms and Migratory Aptitude of Functional Groups
Murakami, Yukito,Hisaeda, Yoshio,Ozaki, Toshiaki,Tashiro, Takako,Ohno, Teruhisa,et al.
, p. 311 - 324 (2007/10/02)
The carbon-skeleton rearrangements as catalyzed by heptamethyl cobyrinate perchlorate, 1ester>ClO4, were investigated under electrochemical conditions.The controlled-potential electrolysis of 2,2-bis(ethoxycarbonyl)-1-bromopropane, which is considered to be a model substrate for methylmalonyl-CoA mutase, was catalyzed by 1ester>ClO4 in N,N-dimethylformamide to give the rearrangement product, 1,2-bis(ethoxycarbonyl)propane, as a major one at -1.5 V vs.SCE in the presence of acetic acid and at potentials more cathodic than -1.8 V vs.SCE without acetic acid in the dark.The electrochemical carbon-skeleton rearrangement was postulated to proceed via formation of anionic intermediates.The electrolyses of 1-bromo-2-cyano-2-ethoxycarbonylpropane, 2-acetyl-1-bromo-2-ethoxycarbonylpropane, and 1-bromo-2-propane with 1ester>ClO4 also afforded the corresponding carbon-skeleton rearrangement products.The results indicated that substrates with two electron-withdrawing groups placed on the β-carbon atom with combination of one carboxylic ester and one of carboxylic ester, acetyl, and cyano moieties readily gave the corresponding rearrangement products which were derived from individual migration of the substituent groups.Substrates with only one of the electron-withdrawing groups, carboxylic ester, acetyl, and cyano, did not give any rearrangement product, but a substrate with one thioester group afforded the corresponding rearrangement product.The migratory aptitude of electron-withdrawing groups was found to decrease in the order: COSR>COR>COOR>CN.Both electronic character and steric bulkiness of the migrating groups are apparently reflected on this tendency, even though relative contributions of these effects are much dependent on the nature of β-substituents.
HOMOLYTIC TRANSFORMATIONS OF 1,3-OXATHIOLANES AT HIGH PRESSURE
Trifonova, V. N.,Zorin, V. V.,Batyrbaev, N. A.,Makarova, Z. G.,Zlotskii, S. S.,et al.
, p. 1386 - 1389 (2007/10/02)
The effect of high pressure was studied on the rate and direction of the homolytic transformations of 1,3-oxathiolanes.Pressure reduces the rate of the transformation of 2-methyl- and 2-isopropyl-1,3-oxathiolanes to ethyl and 2-chloroethyl thoiacylates in the presence of CCl4 to a greater extent than the initiation rate in the system.The selectivity of the formation of the reaction product which is formed more rapidly at normal pressure is increased in the competing homolytic transformations of 2-methyl- and 2-isopropyl-1,3-oxathiolanes to the corresponding ethyl thioacylates with increasing pressure.The yield of the cyclic adduct, 2-methyl-2-hexyl-1,3-oxathiolane, relative to that of linear octyl thioacetate is increased in the homolytic addition of 2-methyl-1,3-oxathiolane to 1-hexane with increasing pressure.
