Total Syntheses of Vicinal Dichloride Monoterpenes Enabled by Aza-Belluš-Claisen Rearrangement.

Diastereoselective syntheses of - and -vicinal dihalides were achieved via an aza-Belluš-Claisen rearrangement, which involved the reaction of an α-chloro carboxylic acid chloride with halogen-substituted -allyl morpholines in the presence of Lewis acids. The developed method was used for the total synthesis of a group of monoterpene natural products bearing vicinal dichloride subunits.