The synthesis of 1-alkenylboronic acid pinacol esters via the palladium-catalyzed cross-coupling reaction of 1-alkenyl halides or triflates with bis(pinacolato)diboron [(Me 4 C 2 O 2 )B-B(O 2 C 2 Me 4 )] was carried out in toluene at 50 °C in the presence of potassium phenoxide (1.5 equivalents) and PdCl 2 (PPh 3 ) 2 •2PPh 3 (3 mol%).The transition metal-catalyzed cross-coupling reaction of disilanes and distannanes is an elegant method for the synthses of organosilicone 1 and -tin 2 compounds directly from organic electrophiles, but the lack of suitable boron nucleophiles has limited this protocol. We have recently demonstrated the synthesis of arylboronates from aryl halides 3 or triflates 4 , and allylboronates from allyl acetates 5 via a palladium-catalyzed cross-coupling reaction of tetra(alkoxo)diborons. Very recently, Matsuda and Murata 6 found that pinacolborane (Me 4 C 2 O 2 )BH is an excellent boron-nucleophile for the palladium-catalyzed coupling reaction in the presence of triethylamine. Thus, tetra(alkoxo)diboron and pinacolborane are two nucleophiles now available for the boron cross-coupling reaction.In this paper, we report the palladium-catalyzed coupling reaction of bis(pinacolato)diboron (1) and 1-alkenyl halides or triflates, which provides a one-step procedure for the synthesis of 1-alkenylboronic esters from vinyl electrophiles (Eq. 1) 7 .