Synthesis and isolation of polytrityl cations by utilizing hexaphenylbenzene and tetraphenylmethane scaffolds

The successful isolation of stable (and soluble) hexa- and tetratrityl cations based on hexaphenylbenzene and tetraphenylmethane scaffold has been accomplished by using readily available starting materials. These robust polytrityl cations can be isolated in crystalline form and stored indefinitely at 0 degrees C. Their structures have been established by (1)H/(13)C NMR spectroscopy and by UV-vis spectroscopy. The structures of these polytrityl cations were further confirmed by quantitative transformations to the reduced (poly)triphenylmethyl derivatives by hydride transfer from triethylsilane, cycloheptatriene, or a borane-dimethyl sulfide complex.