Novel Electron Acceptors Bearing a Heteroquinonoid System. I. Synthesis and Conductive Complexes of 5,5′-Bis(dicyanomethylene)-5,5′-dihydro- Δ 2,2′-bithiophene and Related Compounds

• Published in: Bulletin of the Chemical Society of Japan Vol. 62; no. 5; pp. 1539 - 1546
• Main Authors: Yui, Koji, Aso, Yoshio, Otsubo, Tetsuo, Ogura, Fumio
• Format: Journal Article
• Language: English
• Published: 01.05.1989
• ISSN: 0009-2673; 1348-0634
• DOI: 10.1246/bcsj.62.1539

Abstract Novel electron acceptors bearing a heteroquinonoid system, 5,5′-bis(dicyanomethylene)-5,5′-dihydro-Δ2,2′-bithiophene, its 3,3′-dichloro, 3,3′-dibromo, and 3,3′,4,4′-tetrabromo derivatives, and 5,5″-bis(dicyanomethylene)5,5″-dihydro-Δ2,2′:5′,2″-terthiophene were synthesized by the action of tetracyanoethylene oxide or by Pd(0)-catalyzed substitution reactions with sodium dicyanomethanide on the corresponding α,α′-dihalogenoheteroaromatics. They showed very small on-site Coulomb repulsion as expected, and afforded several highly conductive molecular complexes with electron donors such as hexamethylenetetratellurafulvalene.