Generation of trityl radicals by nucleophilic quenching of tris(2,3,5,6-tetrathiaaryl)methyl cations and practical and convenient large-scale synthesis of persistent tris(4-carboxy-2,3,5,6-tetrathiaaryl)methyl radical

摘要

Tris(2,3,5,6-tetrathiaaryl)methyl cations, which were generated from the corresponding triarylmethanols in the presence of strong acids, underwent reaction with nucleophiles to give trityl radicals, as the product of a one-electron reduction of the carbocation. Depending on the nature of the nucleophile, the only byproducts were either diamagnetic quinone methides or asymmetrical monosubstituted trityl radicals. Herein, we report a protocol for the large-scale synthesis of the Finland trityl, which has the advantage of high overall yield and reproducibility. Tris(2,3,5,6-tetrathiaaryl)methyl cations, which were generated from the corresponding triarylmethanols and strong acids, underwent reaction with nucleophiles to give trityl radicals. Depending on the nucleophile, the only byproducts were diamagnetic quinone methides or asymmetrical monosubstituted trityl radicals. A protocol for the large-scale synthesis of the Finland trityl is reported.