Synthesis and properties of polyacetylenes containing carbazolylmethyl groups

Novel acetylene monomers containing carbazolymethyl groups, 3,5-bis(3,6-di-t-butyl)carbazolylmethyl]-1-ethynylbenzene (1), 3-(3,6-di-t-butyl)carbazolylmethyl-1-ethynylbenzene (2), and 4-(3,6-di-t-butyl)carbazolylmethyl-1-ethynylbenzene (3) were synthesized, and polymerized with (nbd)RhCl]₂-Et₃N, Rh⁺(nbd)η⁶-C₆H₅B⁻(C₆H₅)₃], and WCl₆-n-Bu₄Sn catalysts. The corresponding polyacetylenes with number-average molecular weights ranging from 1600 to 115,000 were obtained in 18%-quantitative yields. The UV-vis absorption band edge wavelengths of the polymers obtained with W catalyst were longer than those of the Rh-based polymers. The photoluminescence quantum yields of the W-based polymers were 1.1-3.1%, while those of the Rh-based ones were 0.18-4.1%.