Enantioselective Construction of Carbocyclic and Heterocyclic Tertiary Boronic Esters by Conjunctive Cross-Coupling Reaction

Synthesis of stereodefined carbocyclicand heterocyclic tertiaryboronic esters is accomplished by performing a conjunctive cross-couplingreaction on preformed cyclic boron ate complexes. Boronates bearingspirocyclic and aryl bicyclic skeletons can be synthesized enantioselectivelyusing a chiral PHOX-ligated Pd catalyst with achiral starting material,while substrates bearing continuous stereogenic centers can be generateddiastereoselectively. A variety of aryl and alkenyl electrophilesare incorporated.