Friedel–Crafts alkylation of benzene with tetrachloromethane
Fonken1 says that the reaction doesn't occur, but it is not due to steric hindrance or instability of tetraphenylmethane since the molecule is actually thermally stable. Instead, it argues that the formation of tetraphenylmethane due to alkylation of benzene using triphenylchloromethane is reversible in nature. The product readily dissociates into triphenylmethyl carbocation and benzene. Due to this unfavourable equilibrium, only insignificant amounts of tetraphenylmethane is formed.

Ben Norris also mentions that the reaction of benzene with tetrachloromethane is used to produce chlorotriphenylmethane, and provided an Organic Synthesis procedure2 that works on the kilogram scale.

References


Fonken, G. J. Alkylation of Benzene with Triphenylmethyl Chloride. J. Org. Chem. 1963, 28 (7), 1909–1909. DOI: 10.1021/jo01042a510.
Bachmann, W. E. Triphenylchloromethane. Org. Synth. 1943, 23, 100. DOI: 10.15227/orgsyn.023.0100.