The synthesis of triphenylmethanol is achieved through a Grignard reaction, utilizing bromobenzene and magnesium to form a Grignard reagent (phenylmagnesium bromide), benzophenone as an electrophile to form a Grignard adduct, and HCl that hydrolyzes into triphenylmethanol.

What is the purpose of utilizing bromobenzene and magnesium in the synthesis of triphenylmethanol?

1) To form a Grignard reagent
2) To form a Grignard adduct
3) To hydrolyze into triphenylmethanol
4) To act as an electrophile

Bromobenzene and magnesium are used to form a Grignard reagent (phenylmagnesium bromide), which is a key nucleophilic component in the synthesis of triphenylmethanol through a Grignard reaction with benzophenone. Thus option 1. To form a Grignard reagent is correct.

Explanation:

The purpose of utilizing bromobenzene and magnesium in the synthesis of triphenylmethanol is to form a Grignard reagent. Bromobenzene, an aryl halide, reacts with magnesium metal in an ether solvent (such as diethyl ether or tetrahydrofuran) to produce phenylmagnesium bromide. This organomagnesium compound is highly reactive due to the polarity of the carbon-magnesium bond, with the carbon end being nucleophilic.

This reactivity is crucial as the phenylmagnesium bromide subsequently acts as a nucleophile in a Grignard reaction, attacking the electrophilic carbonyl carbon of benzophenone to form a Grignard adduct, which is then hydrolyzed by HCl to yield triphenylmethanol.