1,1-Alkenylboration of diarylphosphino-enynes: convenient synthetic entry to vicinal P/B Lewis pairs at extended conjugated π-frameworks

Abstract

Alkenylboranes R-CHCH-B(C₆F₅)₂ undergo carbon–carbon coupling by means of 1,1-alkenylboration with diarylphosphino-enynes to give substituted conjugated hexatriene derivatives that bear a vicinal pair of B(C₆F₅)₂ Lewis acid and PAr₂ Lewis base functionalities at their central carbon portions. A series of six examples was prepared and all compounds were characterized by X-ray diffraction. Consecutive reactions of two selected examples were carried out.