2-Aryl-3-dimethylphosphinylpropionic acids as potential nonsteroidal antiinflammatory agents

Abstract

of 80% formic acid was stirred and heated to 50" for 24 hr. Another 5 ml of 30% HzOz was added and the heating and stirring were continued until an aliquot of the solution failed to give a positive Schiff test (another 24 hr). The volatile components were removed under reduced pressure and the residue was treated with 3.5 g (150 mmol) of LiOH in 35 ml of water. The resulting solution was heated in an autoclave at 120" for 12 hr. A white precipitate was isolated by filtration and washed with several portions of ethanol and then anhydrous ether. The resulting white powder was dried in uacuo to give 2.3 g (56%) of pure 4b. The observed spectral and physical properties were in agreement with those previously reported for this compound.3