I. Photochemical nitration of methoxybenzenes from charge‐transfer complexes with tetranitromethane

The direct irradiation of the charge-transfer (CT) absorption band of the 1/1 electron donor-acceptor complexes of dimethoxybenzenes with tetranitromethane leads to aromatic nitration with a high quantum yield. The analogous methoxytoluenes under the same photochemical conditions are converted in equally high yields to products of aromatic trinitromethylation. This dichotomy with different methoxybenzenes (ArH) is discussed within the context of the common reactive intermediates derived from the CT excitation of the complex. The subsequent interactions of the geminate fragments, i.e., by radical and ion-pair annihilation represent a unifying mechanism for the CT photochemistry leading to aromatic nitration and trinitromethylation.