Copper-catalyzed substitution of allylic carbonates with diboron: A new approach to allylboronate synthesis

Copper-catalyzed γ-selective substitution of allylic carbonates with diboron pro- vides a new method for the efficient synthesis of allylboronates. Optically active α-chiral allylboronates were synthesized through the reaction of chiral allylic carbonates with bis(pinacolato)diboron in the presence of achiral Cu(I)-catalyst with highly efficient chiral- ity transfer. Additionally, in the presence of a chiral Cu(I) catalyst, optically active α-chiral allylboronates were obtained with >90 % ee through the reaction of prochiral substrates with the diboron.