Vicinal Vinylation of Boron-Doped Acenes via Heck Coupling.

Silylated and halogenated benzenes 1,2-(Me3 Si)2 -4,5-X2 -C6 H2 [X = Br ( 3 ), I ( 4 )] are versatile synthetic building blocks. 3 was prepared from known 1,2-(Me3 Si)2 -4,5-Cl2 -C6 H2 via C-Cl borylation/bromodeboronation; CuI-catalyzed Br/I exchange on 3 affords 4 . 3 or 4 and BBr3 yield 9,10-dibromo-9,10-dihydro-9,10-diboraanthracenes (DBAs) 7 or 8 . The B centers were protected with mesityl (Mes; 9 , 10 ) or 2,4,6-tris(trifluoromethyl)phenyl (F Mes; 11 , 12 ) groups. Heck coupling of 9 and styrene/2,3,4,5,6-pentafluorostyrene furnishes the two tetravinyl-substituted green/blue emitters 13 / 14 .