Bis[1-(2-A-2-B)ethenyl]} [2-R.sup.2 -4-X-phenyl- or 1-(2-R.sup.2 -4-X-phenyl) ethenyl]methanes useful as color formers, particularly in transfer imaging, pressure sensitive and thermal-responsive carbonless duplicating systems, are prepared by the interaction of two molecular proportions of the corresponding 1-A-1-B-ethene with the appropriate 2-R.sup.2 -4-X-phenyl-(CH.dbd.CH).sub.n --CHO presence of an acidic catalyst.
Aromatic enamines: para‐Vinylanilines were identified as unique nucleophiles, closely resembling enamines, to undergo CC coupling with aldehydes catalyzed by a simple primary–tertiary diamine/Brønstedacid. The resulting bis(allylic) adducts, which have potential as functional materials, were obtained in high yields under rather mild conditions (see scheme).