Phosphorus trichloride → 3-hydroxy-N-(3-isopropylphenyl)-4-methylbenzamide

Participants

Reaction Conditions

Reaction Steps

3-Hydroxy-4-methylbenzoic acid (1.07 g, 7.00 mmol), 3-isopropylbenzenamine (0.90 mL, 6.4 mmol), and DMAP (0.27 g, 2.2 mmol) were suspended in 25 mL dry toluene in a 2-neck flask with an attached Dean-Stark trap under N2. The mixture was stirred in a 135° C. oil bath and brought to a boil before PCl3 (0.28 mL, 3.2 mmol) was added dropwise by glass/Teflon syringe over 15 minutes. Heating was continued an additional 25 minutes. After cooling, the mixture was diluted with brine and ethyl acetate, and acidified with 1 NHC1. After extraction, the organic layer was dried over anhydrous Na2SO4, concentrated, and purified by flash chromatography (20-50% EtOAc/hexanes) to yield 3-hydroxy-N-(3-isopropylphenyl)-4-methylbenzamide as a white solid after concentration. MS m/z=268 [M−1]−. Calc'd for C17H19NO2: 269.35.

Provenance & Evidence