Pentaleno[1,2-a:4,5′]diacenaphthylenes: Uniquely Stabilized Pentalene Derivatives

• DOI: 10.1021/acs.joc.6b01480
• Publication Date: 2016-08-25T19:41:33Z
• Authors: Bingxin Yuan; Junpeng Zhuang; Kristopher M. Kir...; Chelsea N. Bridgm...; Adam C. Whalley; Lichang Wang; Kyle N. Plunkett
• Keywords: Pentalene; HOMO/LUMO; Ambipolar diffusion; Antiaromaticity

We demonstrate the preparation of diacenaphthopentalene derivatives via a palladium-catalyzed dimerization 1-iodo-2-arylethynyl-acenaphthylenes. The resulting 7,14-diarylpentaleno[1,2-a:4,5a′]diacenaphthylenes, which contain four linearly fused five-membered rings, are benchtop stable and behave as hole-transporting or ambipolar semiconductors in organic field effect transistors. X-ray crystal structure shows important role naphthalene unit that enforces formal pentalene subunit at central rings [5]-radialene-like structures proximal rings. Nucleus-independent chemical shift (NICS) calculations show internal intermediate antiaromaticity character between known dibenzopentalenes derivatives. give high optical gap materials owing to forbidden HOMO LUMO transition, yet have narrow electrochemical gaps reduced small negative potentials giving energy levels −3.57 −3.74 eV.