Preparation and Stille cross-coupling reaction of the first organotin reagents of azulenes. An efficient Pd(0)-catalyzed synthesis of 6-aryl- and biazulenes

The first versatile organometallic reagents of azulenes, 6-(tri-n-butylstannyl)azulenes, have been prepared by a Pd(0)-catalyzed direct stannylation of 6-bromoazulenes with bis(tri-n-butyltin). We demonstrate herein the utility of the reagents in the Stille cross-coupling reaction with aryl and azulenyl halides to afford 6-aryl- and biazulenes in good yield.