Tandem Semipinacol/Schmidt Reaction Leading to a Versatile and Efficient Approach to Azaquaternary Alkaloid Skeletons

A TiCl4-promoted tandem semipinacol/Aubé's type intramolecular Schmidt reaction of α-siloxy-epoxy-azide has been designed and developed
to be a general method for efficient construction of azaquaternary carbon units. As applicable examples, some key tricyclic azaquaternary
skeletons incorporated in many important alkaloids, such as cephalotaxine, stemonamine, erythrinan, and homoerythrinan alkaloids, have
been constructed.

本研究设计并开发了四氯化钛（TiCl4）促进的α-硅氧基环氧叠氮化物串联半频哪醇/Aubé型分子内施密特（Schmidt）反应，将其作为高效构建氮杂季碳单元的通用方法。作为应用实例，本研究已成功构建了多种广泛存在于诸多重要生物碱（如三尖杉碱、百部胺、刺桐类及高刺桐类生物碱）中的关键三环氮杂季碳骨架。