Efficient synthesis of symmetrically and unsymmetrically substituted hexaphenylbenzene analogues by Suzuki-Miyaura coupling reactions

A series of symmetrically and unsymmetrically substituted hexaphenyl benzene (HPB) analogues were efficiently synthesized by using a sterically hindered Suzuki-Miyaura cross-coupling reaction of arylboronic acids with 1,4-diiodo-2,3,5,6-tetraarylbenzenes under our optimized reaction conditions. The 1,4-diiodo-2,3,5,6-tetraarylbenzenes can be readily prepared by using a one-pot Hart reaction. Oxidative cyclodehydrogenation of the dibromo derivative with FeCl3 gave the corresponding hexabenzocoronene (HBC) derivative in good yield.