Palladium-catalyzed cross-coupling reaction of bis(pinacolato)diboron with vinyl triflates β-substituted by a carbonyl group: efficient synthesis of β-boryl-α,β-unsaturated carbonyl compounds and their synthetic utility

摘要

Cross-coupling reaction of bis(pinacolato)diboron withβ-(trifluoromethanesulfonyloxy)-α,β-unsaturated carbonyl compounds was carried outin the presence of PdCl2(PPh3)2-2PPh3 (3 mol%) and KOPh in toluene or K2CO3 indioxane for the synthesis of cyclic and acyclic β-boryl-α,β-unsaturated esters, amides,and ketones in high yields. The vinylboronates thus obtained readily participated incarbon-carbon bond formation, such as cross-coupling with vinyl triflates and 1,4-addition to α,β-unsaturated ketones.