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 hexaphenyl-benzene 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 degreesC. Their structures have been established by H-1/C-13 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.