Addition of Hydrogen Cyanide to Give Cyanohydrins

Wolff-Kishner reduction complements the Cletnmensen and thioacetal desulfurization methods of deoxygenating aldehydes and ketones. Thus, the Clemmensen reduction is unsuitable for compounds containing acid-sensitive groups, and hydrogenation of multiple bonds can accompany desulfurization with hydrogen and Raney nickel. Such functional groups are generally not affected by Wolff-Kishner conditions. 

Wolff-Kishner reduction aids in alkylbenzene synthesis 

We have already seen that the products of Friedel-Crafts acylations may be converted into alkyl benzenes by using Cletnmensen reduction. Wolff-Kishner deoxygenation also is frequently employed for this purpose and is particularly useful for add-sensitive, base-stable substrates. 

Wolff-Kishner Reduction of a Friedel-Crafts Acylation Product 

Propose a synthesis of hexylbenzene from hexanoic acid. 

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