Properties of Star Shaped Thiophene Materials Having a Build-In Photochromic Core

Abstract

A series of star shaped photochromic bisthienylethene derivatives were synthesized by Still coupling reaction and fully characterized. Their photocromic properties were investigated in solution state. With the thiophene or thiazole “arms” attached to a photochromic core, the reversible ring-open and ring-close photoismerization reactions undergoes smoothly when irradiated with ultraviolet and visible light alternately. Molecular geometric structures were optimized and HOMOs/LUMOs were calculated by Dmol³ package of Material Studio. Two key factors, the distance between reactive carbon atoms and the electron distribution in unoccupied orbitals (LUMO), favored the cyclization/cycloreversion triggered by photons.

Keywords:

• Star shaped
• photochromic core
• Stille coupling reaction
• geometric structure
• reactive atoms

Funding

This work was supported by the National Natural Science Foundation of China (grant no. 21072048 and 21272060), the Program for Innovative Research Team in University of Henan Province (grant no. 2012IRTSTHN006), PCSIRT (grant no. IRT1061). This research was supported by the Basic Science Research Program through the National Research Foundation of Korea (NRF) funded by the Ministry of Education, Science and Technology (grant no. 2013054767).