Expeditious and Chemoselective Synthesis of α-Aryl and α-Alkyl Selenomethylketones via Homologation Chemistry
作者:Raffaele Senatore、Laura Castoldi、Laura Ielo、Wolfgang Holzer、Vittorio Pace
DOI:10.1021/acs.orglett.8b00896
日期:2018.5.4
Diselenoacetals, previously considered byproducts in homologation tactics en route to α-selenoketones, are herein found to be excellent starting materials for this purpose. The easy selenium/lithium exchange they undergo affords seleno carbanions which are smoothly added to Weinreb amides to chemoselectively prepare α-aryl- and α-alkyl seleno methylketones through a single chemical operation. No racemization
在此发现,二硒缩醛是先前在与α-硒酮的同源化策略中被认为是副产物的副产物,在此被认为是极好的起始原料。它们易于进行硒/锂交换,从而得到硒代碳负离子,将其平稳地添加到Weinreb酰胺中,即可通过一次化学操作化学选择性地制备α-芳基-和α-烷基硒代甲基酮。在光学纯的起始原料的存在下未观察到外消旋作用。