CAPABILITY OF OXY AND THIO GROUPS TO BEHAVE AS PL-DONORS OR PL-ACCEPTORS - LIMITING CASE OF THE RADICAL-ANIONS OF MONOSUBSTITUTED BENZENES

INDO computations have been carried out for the symmetric and antisymmetric configurations of the radical anions C6H5OR and C6H5SR. It is found that in these species the OR and SR groups, which are π donors in the planar conformation, can also act as π acceptors in the orthogonal conformation. The electron acceptor ability is larger for the SR group and accordingly it is found that the most stable conformation of the C6H5SR radical anions is the orthogonal one. An MO rationalization of these results is offered. © 1979 American Chemical Society.