Steric hinderance between the ortho hydrogens makes it impossible for the three phenyl rings to be coplanar. Instead the triphenylmethyl.

Steric hinderance between the ortho hydrogens makes it impossible for the three phenyl rings to be coplanar. Instead

the triphenylmethyl carbocation assumes a “propeller” conformation with the phenyl rings pitched at a 32° angle.

The triphenylmethyl cation can be prepared by reaction of a Grignard reagent with benzophenone to form triphenylmethyl

alcohol. Treatment with fluoboric acid results in the trityl carbocation.

Safety Notes for Expt. 30 – Synthesis of Triphenylmethanol and the Trityl Carbocation

Physical Properties of the Reactants and Reagents in Expt. 30

IR Spectra of bromobenzene and benzophenone

Setup of the round-bottom flask, Claisen adapter, West condenser and addition funnel

A drying tube is added to the top of the condenser