The Reactions Of Methylenecyclopropylketones With Diorganolithium Cuprates

Abstract

Methylenecyclopropanes have recently been the subject of several interesting mechanistic! and synthetic2 studies. Although its exocyclic double bond imposes additional strain on the three-membered ring,3 methylenecyclopropane (b.p. 11°C) is surprisingly stable. It is now available on a kilogram scale4 and can be stored in a cylinder for several years at room temperature without significant decomposition.5 It is interesting to note that some naturally occurring compounds (including hypoglycin A)6 contain this highly strained unit.