Synthesis of functionalized tetracene dicarboxylic imides

For the first time, a synthesis of tetracene dicarboxylic imides was established with 1,2,3,4-tetrahydrotetracene (1) instead of tetracene as the starting material. Mono-bromination of 1 by CuBr2 followed by a Friedel-Crafts reaction, oxidation, and imidization gave the tetrahydrotetracene carboxylic imides 5a-b. Subsequent oxidative dehydrogenation of 5a-b with DDQ afforded the functional tetracene dicarboxylic imide monobromides 6a-b. which can be further functionalized to provide functional materials such as the 'donor-acceptor' type compounds 7a-b. (C) 2010 Elsevier Ltd. All rights reserved.