Thin Films of Polymerized Rodlike Phthalocyanine Aggregates

We report here the synthesis, characterization, and thin film formation of a polymerizable octa-substituted phthalocyanine (Pc) with styryl-terminated side chains, CuPc(OCH2CH2OCH2CHCHPh)8, 2,3,9,10,16,17,23,24-octakis(2-cinnamyloxyethoxy) phthalocyaninato copper(II) (1). We compare this Pc with a previously discussed phthalocyanine, also possessing styryl groups at the termini of the side chains, but with one alkoxy group in the side chain removed, CuPc(OCH2CH2CHCHPh)8 (2) (J. Am. Chem. Soc. 2001, 123, 3595). Both 1 and 2 are related to the octa-substituted phthalocyanine CuPc(OCH2CH2OBz)8, 2,3,9,10,16,17,23,24-octakis (2-benzyloxyethoxy) phthalocyaninato copper(II) (3), which has been shown to form highly coherent rodlike aggregates in Langmuir−Blodgett (LB) films, with excellent control of rod orientation (J. Am. Chem. Soc. 1999, 121, 8628; Langmuir 2001, 17, 7071). Irradiation of the styryl π−π* absorbance bands (254 nm) for horizontally transferred LB films of 1 and 2 results in stabilization of thei...