Objective

Reactions of Haloarenes with metals When the magnesium metal reacts with bromobenzene and iodobenzene in presence of ether to form Grignard reagent. Chlorobenzenes are relatively unrecative and are generally not used for preparation of Grignard reagent.

In case of 1-bromo-3-chlorobenze reacts and magnesium metals in dry ether, the formation of Grignard reagent occurs selectively from the side of aryl bromide. The order of reactivity of aryl halides or (haloarenes) towards the magnesium metal is as follows: Aryl iodine > Aryl bromide >

Wurtz-Fittig reaction A mixture of an alkyl halide and aryl halide gives an alkylarene when treated with sodium in dry ether and is called Wurtz-Fittig reaction.

Fittig reaction When two aryl halides treated with sodium in dry ether, to form biphenyl along with sodium halides. It is called Fittig reaction.

Ullmann reaction Haloarens on refluxing result in formation of biphenyl. This reaction occurs through coupling of phenyl radical to form biphenyl. This reaction is called Ullmann reaction.