A Synthesis of (E)-(1-Organo-1-alkenyl)boronates by the Palladium-Catalyzed Cross-Coupling Reaction of (E)-1,2-Bis(boryl)-1-alkenes with Organic Halides: A Formal Carboboration of Alkynes via the Diboration-Coupling Sequence

Abstract (E)-1,2-Bis(boryl)-1-hexene, prepared by the platinum-catalyzed diboration of 1-hexyne with bis(pinacolato)diboron, regioselectively cross-coupled with aryl, 1-alkenyl, benzyl, and allyl halides in the presence of a palladium catalyst and a base to provide the corresponding pinacol esters of (E)-(1-butyl-1-alkenyl)boronic acid in good yields.