By Witting reaction of omicron-xylylenebis(triphenylphosphonium bromide) (1) with aldehydes (2) and formaldehyde in the presence of base, unsymmetrically substituted omicron-divinylbenzenes (3) have been prepared in one pot.
SINDLER-KULYK, MARIJA;SPELJERIE, LIDIJA;MARINIC, ZELJKO, HETEROCYCLES, 29,(1989) N, C. 679-682