Iridium-catalysed 3,5-bis-borylation of phthalonitrile enables access to a family of C4h octaarylphthalocyanines

Abstract

Ir-catalysed borylation of phthalonitrile produces both 4-(Bpin)phthalonitrile (1) and 3,5-bis(Bpin)phthalonitrile (2), which are potential divergent intermediates for the synthesis of functionalized phthalocyanines. To exemplify the utility of 2, we have prepared a series of 3,5-bis-arylphthalonitriles that in turn undergo sterically controlled regioselective cyclotetramization to give previously unknown C_4h 1,3,8,10,15,17,22,24-octaarylphthalocyanines.