Synthesis of 3-Acyl-4-alkenylpyrrolidines by Platinum-Catalyzed Hydrative Cyclization of Allenynes
作者:Takanori Matsuda、Sho Kadowaki、Masahiro Murakami
DOI:10.1002/hlca.200690165
日期:2006.8
A series of nitrogen-tethered allenynes (‘5-aza-1,2-dien-7-ynes’) 1 were transformed to the corresponding 3-acyl-4-alkenylpyrrolidines 3 when treated with a catalytic amount of PtCl2 in MeOH at 70°. Initial Pt-promoted cyclization forms a nonclassical carbocationic intermediate. In contrast to the cycloisomerization in toluene, which produced the bicyclic cyclobutenes 2, the intermediate is intercepted
当在甲醇中于MeOH中催化量的PtCl 2处理时,将一系列氮系链烯丙炔('5-氮杂-1,2-二烯-7-炔')1转化为相应的3-酰基-4-烯基吡咯烷3 70°。最初的Pt促进的环化反应形成非经典的碳阳离子中间体。与产生双环环丁烯2的甲苯中的环异构化相反,中间体通过添加氧亲核试剂被拦截,从而实现了正式的水合环化。