The Synthesis of Benzoins

Ide, Walter S.; Buck, Johannes S.


Benzoins are aromatic alpha-hydroxy ketones of the general formula, Ar’CHOHCOAr. Similar compounds containing aromatic heterocyclic nuclei are also classed as benzoins. The reactions for the preparation of benzoins are (1) the condensation of two molecules of an aromatic aldehyde in the presence of cyanide ion; (2) the conversion of an unsymmetrical benzoin into it into its isomer; (3) condensation of an aryl glyoxal with an aromatic hydrocarbon; (4) the reaction of an aryl Grignard reagent with mandelamide or mandelonitrile; (5) the reduction of a benzyl; (6) the reduction of an aromatic acid or its derivatives; (7) the introduction of a hydroxyl group into a desoxybenzoin; (8) and some miscellaneous reactions. These are the subject of this chapter