α-Alkylidene-γ-butyrolactone synthesis via one-pot C–H insertion/olefination: substrate scope and the total synthesis of (±)-cedarmycins A and B
摘要:
A system for the synthesis of alpha-alkylidene-gamma-butyrolactones via a one-pot C-H insertion/olefination sequence is described. The process is based on the rhodium catalysed C-H insertion reaction of alpha-diazoa-(diethoxyphosphoryl)acetates. The mild reaction conditions, operational simplicity and ready availability of starting materials are all key features. A wide range of successful reaction systems are reported (41 examples) highlighting the generality of the method. The application of this method in the total synthesis of the natural products (+/-)-cedarmycins A and B is also described. (C) 2014 Elsevier Ltd. All rights reserved.