Structures and Conformational Analysis of 1,8-Bis(9-triptycylethynyl)anthracene and Its Derivatives as Prototypes of Molecular Spur Gears

Abstract

Abstract The title compounds having two 9-triptycyl rotors, two acetylene shafts, and an acene base were synthesized by coupling reactions as molecular spur gears. Their molecular structures were compared to evaluate the meshing of rotor moieties and the orientation of the two gear shafts. The mechanism of rotation of three-toothed rotors was explored by NMR spectroscopy and DFT calculations in terms of gear rotation and slippage.