Vitamin B12S-promoted model rearrangement of methylmalonate to succinate is not a free radical reaction.
Vitamin B12S-promoted model rearrangement of methylmalonate to succinate is not a free radical reaction.
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维生素 B12S 促进的甲基丙二酸至琥珀酸的模型重排不是自由基反应。
DOI：
10.1073/pnas.87.8.3174
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发表时间：
1990
影响因子：
11.1
通讯作者：
Dowd,P
中科院分区：
文献类型：
--
作者：
Choi,GY;Choi,SC;Galan,A;Wilk,B;Dowd,P
为了探测由维生素B12促进的甲基丙二酸酯到琥珀酸酯重排模型中的自由基中间体，设计了具有戊烯基侧链自由基捕获器的模型系列。控制自由基，溴甲基-戊烯基丙二酸硫酯的三正丁基锡氢化物处理产生的，经历快速环化的六元环，和预期的，没有琥珀酸重排产物被检测到。相比之下，当溴化物用维生素B12处理时，几乎没有观察到环化产物;主要产物是戊烯基琥珀酸酯。这一结果表明，后者重排不遵循自由基途径。
To probe for free radical intermediates in the model methylmalonate to succinate rearrangements promoted by vitamin B12s, a model series with a pentenyl side chain radical trap has been devised. The control free radical, generated by tri-n-butyltin hydride treatment of bromomethyl-pentenylmalonate thioester, undergoes rapid cyclization to the six-membered ring, and, as anticipated, no succinate rearrangement product is detected. By contrast when the bromide is treated with vitamin B12s, little cyclized product is observed; the major product is the pentenyl succinate. This result demonstrates that the latter rearrangement does not follow a free radical pathway.