Journal of the Chemical Society. Perkin transactions II p. 61 - 70 (1988)
Update date:2022-08-03
Topics:
Dowd, Paul
Hershline, Roger
The model rearrangement mimicking the coenzyme B12-dependent, enzyme-catalysed interconversion of α-methyleneglutaric acid with methylitaconic acid has been carried out with a carbon-13 label.This experiment demonstrates beyond doubt that the acrylate group is the migrating group in the model, as it is in the enzyme-catalysed rearrangement.Experiments designed to probe the possible occurence of cyclopropylmethyl intermediates in the model rearrangement are also described.To this end the cis- and trans-bromomethylcyclopropanediacids (16a) and (20a) were prepared starting from the common precursor cyclopropane-1,1,2-tricarboxylic acid (13).Thus, (13) was converted into the anhydride (14) which was, in turn, reduced to the lactone (15).Opening of the lactone with HBr in acetic acid gave the desired trans-diacid (16a).For the cis-diacid (20a), the anhydride (14) was hydrolysed, esterified with diazomethane, then reduced with lithium triethylborohydride.Conversion of the resulting alcohol (19) into the bromide (20a) was effected with phosphorus tribromide.An extensive series of experiments involving treatment of the acids and their methyl and tetrahydropyranyl esters with vitamin B12s was carried out.No methylitaconic acid (3a) could be detected in any of the reaction mixtures.However, α-methyleneglutaric acid (2a) and methylglutaconic acid (21) were observed as the reaction products.The methyl toluene-p-sulphonate (22) and iodide (23) were also examined and yielded results analogous to those obtained with the bromides.
View MoreZhejiang Kente Chemical Co.,Ltd.
Contact:86-0576-87651912
Address:No.7, Fengxi West Road, Modern Industrial Zone
Shanghai HengXun Pharmaceutical Tech. Co., Ltd.
Contact:86-86-52730756
Address:Room 603, No. 240, Tianmuzhong Road, Zhabei, Shanghai, China
Changzhou BaoKang Pharmaceutical & Chemical Co., Ltd
Contact:(86) 519-88782201 88784080 88785278
Address:Henglin town, changzhou,Jiangsu
Guangzhou Probig Fine Chemical Co., Ltd.
Contact:020-86297874
Address:No.2, 1/F, No.20, Hetai Road,Hebian Village, Baiyun District,Guangzhou,China
Zhejiang Haizhou Pharmaceutical Co., Ltd.
website:https://www.haizhoupharma.com/
Contact:+86-576-88221016
Address:No. 19, Donghai 5th Avenue, Yanhai Industrial Zone, Linhai, Zhejiang, China
Doi:10.1002/chem.201905468
(2020)Doi:10.1016/0031-9422(74)80336-5
(1974)Doi:10.1021/ja01233a027
(1944)Doi:10.1246/bcsj.59.3505
(1986)Doi:10.1093/oxfordjournals.intqhc.a002616
(1940)Doi:10.1021/jm00333a001
(1964)