1,5-Stereocontrol in Bismuth-Mediated Reactions between Aldehydes and Allyl Bromides: Stereoselective Synthesis of Open-Chain all-syn- and anti, anti-1,3,5-Disposed Trimethylalkanes
作者:Eric Thomas、Norazah Bazar、Sam Donnelly、Hao Liu
DOI:10.1055/s-0029-1219357
日期:2010.3
The reaction of 5-benzyloxy-2,4-dimethylpent-2-enyl bromide with the bismuth species generated by reduction of bismuth(III) iodide by zinc powder gives an intermediate which reacts with aldehydes with useful levels of stereocontrol in favour of 1,5-anti-(3E)-5-methylalk-3-enols. Manipulation of protecting groups, stereoselective hydrogenation, and tosylate displacement using a higher-order cyanomethylcuprate
5-苄氧基-2,4-二甲基戊-2-烯基溴化物与通过锌粉还原碘化铋(III)产生的铋物质的反应产生一种中间体,该中间体与醛反应,具有有用的立体控制水平,有利于1, 5-抗-(3E)-5-methylalk-3-enol。使用高级氰基甲基铜酸盐处理保护基团、立体选择性氢化和甲苯磺酸酯置换,可生成全顺式或反、反 1,3,5-处置的三甲基烷烃。