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 °C. Their structures have been established by 1H/13C 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.