1-Naphthaldehyde → 2-[(Naphthalen-1-yl)methylidene]butanedioic acid

Participants

Reaction Steps

To a solution of 32.3 g of ethyl succinate and 29.0 g of 1-naphthaldehyde in 320 ml of an absolute ethyl alcohol was added 10.7 g of a 50% sodium hydride (dispersion in mineral oil) under ice-cooling, and the mixture was heated under reflux for 30 minutes. To the reaction mixture was added 230 ml of a 1N-aqueous sodium hydroxide solution, and the mixture was concentrated under reduced pressure. To the residue was added water, and the mixture was extracted with ethyl ether to remove neutral materials. The aqueous layer was acidified with a concentrated hydrochloric acid, and extracted with ethyl ether. The ethereal layer was washed with a saturated sodium chloride aqueous solution, dried over anhydrous magnesium sulfate and evaporated under reduced pressure. To the residue was added benzene, and precipitated crystals were collected by filtration to obtain 26.5 g of 2-(1-naphthylmethylene) succinic acid as yellow crystals.

Provenance & Evidence