STRUCTURE OF 1,4-BENZENEDICYANAMIDE DIANION DERIVATIVES

The crystal structures of four tetraphenylarsonium salts of 1,4-dicyan amidebenzene derivatives, namely, bis(tetraphenylarsonium) 1,4-benzene dicyanamide(2-), bis(tetraphenylarsonium) 2,5-dimethyl-1,4-benzenedicy anamide(2-), bis(tetraphenylarsonium) 2,5-dichloro-1,4-benzenedicyanam ide(2-) and bis(tetraphenylarsonium) 2,3,5,6-tetrachloro-1,4-benzenedi cyanamide(2-), were determined. All of the derivatives are essentially planar with the cyanamide groups in an anti configuration, suggesting a significant degree of pi coupling between the cyanamide groups and phenyl ring. No evidence was seen of pi stacking for any of the 1,4-di cyanamidebenzene dianion derivatives.