New redox materials based on functionalised 9,10-anthracenediylidenes

The syntheses, electronic, optical and structural properties of a range of derivatives of 9,10-anthracenediylidene are described. The first family of compounds are rr-electron donors based on 9,10-bis(1,3-dithiol-2-ylidene)-9 ,10-dihydroanthracene Recent synthetic developments are reviewed, including the functionalisation, via lithiation and subsequent In situ quenching wit h electrophiles, of the trimethyl derivative 8. X-Ray crystal structures of selected derivatives reveal that the molecules adopt a saddle-shaped confo rmation. The second family of compounds are novel single-component donor-pi -acceptor species which possess intramolecular charge transfer, notably 10- (4,5-dimethyl-1,3-dithiol-2-ylidene)-9-(2,2-dicyanomethylene)anthracene 19. Cyclic voltammetric data, UV/visible spectra, ultrafast time-resolved spec troscopy and X-ray structural data are reported.