Diastereoselective Synthesis of Boryl-Substituted Vinylcyclopropanes via Deborylative Cyclization of Geminal Diboron Compounds

Herein we report a diastereoselective synthesis of boryl-substituted vinylcyclopropanes, a class of highly valuable synthetic building blocks, via deborylative cyclization of geminal diboron compounds. The method exhibits broad functional group tolerance and accommodates diverse alkyl and aryl α-substituents. The diastereoselectivity is primarily governed by the α-substituent (alkyl vs aryl), while olefin geometry in the side chain has a secondary influence. Mechanistic studies indicated distinct pathways: a concerted process for alkyl substrates and a carbanion intermediate for aryl derivatives. Synthetic utility of the products was also demonstrated.