[ARENE-CENTER-DOT-ME(3)C(-PHASE (TRIFLUORO)METHYLATION OF TERT-BUTYL-SUBSTITUTED DIPHENYLALKANES()] NONCOVALENT COMPLEXES IN THE GAS)

The reaction of Me(2)F(+), Me(2)Cl(+) and CF3+ with p-Me(3)CC(6)H(4)(C H2)(n)C6D5(n = 2, 3) initiates a reaction pattern whose major features are accounted for by the additional electrostatic stabilization affor ded by the second (spectator) aromatic ring on ionic intermediates and ion-molecule complexes, The Me(3)C loss following CX(3)(+)(X, = H,F) addition to the tert-butyl-substituted ring is significantly reduced w ith respect to a single-ring model substrate, p-Me(3)CC(6)H(4)Me. [Are ne . Me(3)C(+)] non-covalent complexes mediate the observed interannul ar and intermolecular Me(3)C(+) transfer. Unimolecular cleavage of Me( 3)CH from [arene . Me(3)C(+)], following side-chain H- abstraction, a major fragmentation pathway under mass spectrometric conditions, is in stead largely inhibited in the reported radiolytic experiments. Such b ehavior is accounted for by the effective stabilization of ion-molecul e non-covalent complexes ensured by unreactive collisions with about 1 atm bath gas.