Preparation of alpha-Hydroxy Ketones from Aromatic Aldehydes

Benzoin condensation of some aromatic aldehydes was investigated by catalytic effect of cyanide ion in alcoholic solvents. Some aldehydes including 4-methylbenzaldehyde, 4-chlorobenzaldehyde, 2-furylcarbaldehyde and 4-pyridinecarbaldehyde were converted to their relative ?-hydroxy ketones. 2-Pyridinecarbaldehyde yielded an endiol tautomer of its relative ?-hydroxy ketone, and 4-nitrobenaldehyde was converted to unexpected esters in the same conditions.