Syntheses and Properties of 2,2'-Binaphtho-1,3-dithiinylidene and Its Selenium Analog, 2-(1,3-Dithiol-2-ylidene)naphtho-1,3-dithiin, and 2-(4H-Thiopyran-4-ylidene)naphtho-1,3-dithiin

Article abstract of DOI:10.1246/bcsj.61.953

In order to discover new electron donors for conducting charge-transfer complexes, the four title compounds 1-4 composed of two heterocycles have been prepared via 1,8-dichalcogen-bridged naphthalene.The cyclic voltammetery indicates that symmetrical 1 and 2 are poor donors, but unsymmetrical 3 and 4 possess considerable donor abilities.The latter compounds are thus capable of forming some crystalline charge-transfer complexes with strong acceptors such as TCNQ, TCNQF4, and DDQ, which are, however, semi-conducting.