Preparation, Structure, and Redox Behavior of Bis(diarylmethylene)dihydrothiophene and Its π-Extended Analogues
摘要:
The preparation, X-ray structure, and optoelectronic properties of bis(diarylmethylene)dihydrothiophene 1 and its p-extended analogues 2 are described. The development of a simple, short-step synthetic route allowed us to prepare derivatives with different aryl units. X-ray crystallographic analysis of 1b and 2b revealed their quinoidal structures, which exhibit strong electronic absorption in the visible region. Cyclic voltammetry measurements revealed their strong electron-donating properties. 1b showed two-step electrochromic behavior between the corresponding radical cation and dication.
A series of 2,5-bis(diarylmethylene)-2,5-dihydrothiophenes and their furan, selenophene, and N-methylpyrrole analogs were synthesized in three steps either starting from 2,5-dilithiated five-membered heteroaromatics and 2 equiv of diaryl ketones or from 2,5-diaroyl five-membered heteroaromatics and 2 equiv of aryllithiums.