A New Synthetic Route to (±)‐Perhydrohistrionicotoxin

Abstract
Starting from ethyl 2‐cyclohexen‐1‐carboxylate (3) the total synthesis of the perhydrohistrionicotoxin intermediate 23 was achieved in 25% overall‐yield. The two key steps involve a positionally specific addition of HOBr to the oxime‐olefin 7 and the alkylation of bromooxime 17 with 1‐lithio‐1‐butyne. The latter represents a novel method for stereospecific and position‐specific introduction of a nucleophilic butyl equivalent in α‐position to a ketonic carbonyl group.