Rh(III)-Catalyzed C–H Activation-Initiated Directed Cyclopropanation of Allylic Alcohols

We have developed
a Rh­(III)-catalyzed diastereoselective [2+1]
annulation onto allylic alcohols initiated by alkenyl C–H activation
of N-enoxyphthalimides to furnish substituted cyclopropyl-ketones.
Notably, the traceless oxyphthalimide handle serves three functions:
directing C–H activation, oxidation of Rh­(III), and, collectively
with the allylic alcohol, in directing cyclopropanation to control
diastereoselectivity. Allylic alcohols are shown to be highly reactive
olefin coupling partners leading to a directed diastereoselective
cyclopropanation reaction, providing products not accessible by other
routes.