Nitric Acid → Phthalaldehyde

Participants

Reaction Conditions

Reaction Steps

In a 1000-ml three-neck flask equipped with a thermometer, a reflux condenser and a stirrer were placed 50 g of o-xylylene glycol, 39.2 g of 60% by weight nitric acid, 197.6 g of water, and 213.2 g of acetic acid. The mixture was raised in temperature to 70° C. on an oil bath and was stirred under these conditions for 2 hours. After cooling, the reaction mixture was analyzed by gas chromatography to find that the raw material o-xylylene glycol was completely absent and that phthalaldehyde was formed in a yield of 60%. In addition, phthalide (yield: 6%) and an ester of the raw material were formed as by-products. The obtained reaction mixture was extracted with two portions of toluene, the organic layer was distilled and thereby yielded phthalaldehyde in a yield of 45% on the basis of o-xylylene glycol. Gas chromatographic analysis revealed that phthalaldehyde had a purity of 95.0%. In addition, phthalide was formed in a yield of 10%.

Provenance & Evidence