Diindeno-Fused Corannulene-Extended Tetrathiafulvalenes

Abstract

Two regioisomeric extended tetrathiafulvalenes (TTFs) incorporating diindeno-fused corannulene spacers were synthesized from suitable dione precursors using Horner-Wadsworth-Emmons olefination reactions. Both compounds are strong chromophores with a longest-wavelength absorption that exhibited some degree of charge-transfer character as inferred from solvatochromic behaviors and frontier orbital calculations. The compounds underwent two reversible one-electron oxidations and a quasi-reversible third oxidation during cyclic voltammetry conditions. The mono- and dications had characteristic NIR absorptions and both were EPR active. The dications with potential diradicaloid characters underwent reactions when generated in bulk.