Complexes a transfert de charge a caractere metallique a partir de donneurs d'electrons derives de bis(chalcogenopyrannylidenes)
The synthesis of electron donor compounds in the 2:2' and 4:4'-bi(thiopyranyliden) series and 4:4'-bi(selenopyranyliden) series is described following several ways.The Z structure of the 2:2'-bi(4,6-diarylthiopyranyliden) is established by means of dipole