The reduction of aromatic compounds to 1.4-cyclohexadiene compounds in presence of alkali metal liquid ammonia and an alcohol is called Birch reduction. A variety of aromatic compounds containing electron donating or electron withdrawing groups could be readily converted to the corresponding 1,4 cyclohexadiene derivatives. The regioselectivity towards the products in Birch reduction of substituted aromatic compound depends on the nature of the substituent. For example, the electron donating substituent such as alkyl or alkoxy group remains on the unreduced carbon where as the electron withdrawing groups such as carboxylic acid or primary amide remains on reduced carbon almost exclusively. The aldehydes and esters groups are in the electron donation side because these are reduced to the corresponding alcohols in Birch condition before the reduction of aromatic ring . The addition of one or two equivalent of water ...
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