Alkoxy-substituted hexastyrylbenzenes

Star-shaped compounds 2a-e with a central benzene ring and six p-substituted, (E)-configured styryl groups have been prepared by a sequence of three-fold Heck and three-fold Wittig-Horner reactions. Alkoxy chains (OC3H7, OC6H13, OC10H21, OC12H25) on all six arms guarantee a good solubility of 2a-d, whereas the alternating hexyloxy and cyano substitution in 2e leads to an almost insoluble push-pull system. Irradiation into the long-wavelength absorption of 2a-d (with lambda(max) values of 341-342 nm) results in a statistical photocross-linking, which is characterized by the complete degradation of all stilbene chromophores.