REFINED INSIGHT IN STEREOCHEMICAL AND DIRECTIONAL FEATURES OF THE FE(1)-MEDIATED DEHYDROGENATION OF TETRALIN

Experimental results demonstrate that, in the course of gas-phase Fe+- mediated dehydrogenation of tetralin, the metal ion sticks to the same plane of the hydrocarbon surface. The study of 5-substituted, labeled tetralin analogues reveal the operation of an interesting substituent effect: Steric hindrance imposed by a CH3 group at C(5) deflects the metal to the more easily accessible region of C(1)/C(2); in contrast, a CH3O substituent at C(5) directs the metal ion to the more congested C(3)/C(4) region which clearly points to a coordination of Fe+ to the MeO group in the course of the haptotropic migration.