Reversing the Reactivity of Carbonyl Functions with Phosphonium Salts: Enantioselective Total Synthesis of (+)-Centrolobine
作者:Hiromichi Fujioka、Kenzo Yahata、Ozora Kubo、Yoshinari Sawama、Tomohito Hamada、Tomohiro Maegawa
DOI:10.1002/anie.201106046
日期:2011.12.16
Step saver: Carbonyl groups with lower reactivities can be transformed in the presence of more reactive ones by treatment with PPh3 (or PEt3) and TMSOTf prior to the reaction (see scheme; TMS=trimethylsilyl, Tf=trifluoromethanesulfonyl). This methodology can be applied to reduction and alkylation reactions, and enabled the short asymmetric total synthesis of (+)‐centrolobine with the highest overall
节省步骤的方法:在反应之前,可以通过用PPh 3(或PEt 3)和TMSOTf处理,在反应性更高的羰基存在下转化(参见方案; TMS =三甲基甲硅烷基,Tf =三氟甲磺酰基)。该方法学可用于还原和烷基化反应,并实现了迄今为止报道的最高总收率的(+)-中心ro素的短时不对称全合成。