Arsenic Acid → 8-Methylquinoline-7-carboxylic acid

Participants

Reaction Conditions

Reaction Steps

A mixture of 3-amino-2-methylbenzoic acid (18) (6.1 g, 39.7 mmol), arsenic acid (7.4 g, 52.3 mmol), and glycerol (5.8 mL, 79.4 mmol) in sulfuric acid (9 mL) was heated at 160° C. for 5 hours. The reaction mixture was cooled to room temperature and diluted with water. The mixture was filtered through a bed of celite and the filtrate was adjusted with 2 M NaOH to pH˜6. The aqueous layer was extracted numerous times with chloroform/isopropanol. The pooled organic layers were removed under vacuum. The solid residue was triturated with chloroform. The mixture was to filtered, and the solid was washed with hexane and dried under high vacuum to give 8-methylquinoline-7-carboxylic acid (19) 3.86 g (20.6 mmol, 52% yield).

Provenance & Evidence