Iron(III)/NaBH4-mediated additions to unactivated alkenes: synthesis of novel 20'-vinblastine analogues.

An Fe(III)/NaBH(4)-mediated reaction for the functionalization of unactivated alkenes is described defining the alkene substrate scope, establishing the exclusive Markovnikov addition, exploring a range of free radical traps, examining the Fe(III) salt and initiating hydride source, introducing H(2)O-cosolvent mixtures, and exploring catalytic variants. Its use led to the preparation of a novel, potent, and previously inaccessible C20'-vinblastine analogue.