摘要：

A series of C3-symmetric π-conjugated compounds containing three to six o-carborane clusters have been synthesized by employing palladium-catalyzed Suzuki coupling reactions and palladium-catalyzed acetylation reactions, followed by silicon tetrachloride mediated trimerization reactions. Carborane-containing extended trimers were found to emit blue light. Incorporation of o-carborane clusters into extended π-conjugated systems led to 22−70% enhancement of their relative fluorescence quantum yields. Decapitation of o-carborane clusters made these extended trimers water soluble, and their aqueous solutions were also found to be fluorescent, but with a reduced fluorescence intensity. The carborane-appended π-conjugated compounds are found to be extremely thermally stable, and for some of these compounds only 10% mass loss occurred at temperatures close to 500 °C. The DSC thermograms of smaller Ccage-appended trimers indicate the occurrence of solid−solid phase transitions.

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