Synthesis and Molecular Properties of Four Isomeric Dialkylated Angular-Shaped Naphthodithiophenes

A new strategy to synthesize 4,9- and 5,10-dialkylated alpha-aNDTs as well as 4,9- and 5,10-dialkylated beta-aNDTs is described. Four isomeric precursors with different dithienyl-ene-diyne arrangements undergo base-induced double 6 pi-cyclization to construct the central naphthalene cores, leading to the formation of the regiospecific products. These 2,7-distannylated dialkylated aNDT-based monomers can be used for Stille cross-coupling to produce promising conjugated materials for various optoelectronic applications.