Property of intramolecular charge transfer compounds Dδ+-π-Aδ– derived from TCNQ derivatives

The molecular and crystal structures of some of the Stork enamine-type reaction products between 1,3,3-trimethyl-2-methyleneindoline and TCNQ derivatives were determined. The molecular structures of these products are characterized by the dihedral angle θ between the planes of the donor and acceptor parts of the molecule. The ionicity δ and molecular structure of intramolecular charge transfer compounds D δ+ -π-A δ- were discussed.