Ammonia → 3-Phenoxybenzaldehyde

Participants

Reaction Steps

A solution of formalin (40%, 150 ml) was cooled to 10° C and then treated with aqueous ammonia solution (35%, 75 ml) over 15 minutes. A mixture of 3-phenoxybenzyl chloride and 3-phenoxybenzal chloride containing 70% monochloride chloride and 30% dichloride mixture (50 g) was added and the mixture stirred under a nitrogen blanket for 3 hours. The mixture was then acidified with acetic acid (150 ml), stirred for a further 3 hours in the cold, and then refluxed for 4 hours. After cooling, the reaction mixture was extracted with toluene (100 ml) and the extract washed neutral with sodium bicarbonate solution. The toluene solution of crude 3-phenoxybenzaldehyde was diluted with an equal quantity of ethanol and then stirred with a saturated aqueous solution of sodium bisulphite. The resulting bisulphite adduct was filtered off and washed with toluene. After vacuum drying, this gave 63.0 g of purified 3-phenoxybenzaldehyde bisulphite compound which on treatment with dilute mineral acid yielded the pure 3-phenoxybenzaldehyde. Yield based on chloride mixture was 95%.

Provenance & Evidence