A facile approach to the synthesis of substituted dibenzofulvenes-precursors to pi-stacked poly(dibenzofulvene)s

A series of novel substituted (2-methoxy, 2-nitro, 2-bromo, 2-iodo, 2-cyano, and 2-acetyl) and disubstitiuted (2-bromo-7-methoxy, 2-bromo-7-propoxy, 2-bromo-7-hexoxy, 2-nitro-7-propoxy, 2-nitro-7-hexoxy, and 2,7-di-bromo) dibenzofulvenes have been prepared from the corresponding fluorenes with fair to very good overall yields (35.7-66.7%) based on the Wittig chemistry. The new approach enjoyed much simpler experimental procedures and has the advantage of higher functional group tolerance. Preliminary results on their polymerization using solution free-radical approach are also presented.