p-Toluenesulfonic acid monohydrate → HCID 91002123, compound

Participants

Reaction Steps

A mixture of Example 695C (0.3 g, 0.91 mmol) and TsOH.H2O (0.35 g, 1.82 mmol) in toluene (50 mL) was heated to reflux for 20 hours using a Dean-Stark trap to remove water. The reaction was cooled to room temperature, concentrated under vacuum, diluted with ethyl acetate, washed with saturated NaHCO3 and brine, dried (MgSO4), filtered, and concentrated under vacuum. The residue was purified by flash column chromatography on silica gel with 7:3 hexanes/ethyl acetate to provide 0.21 g (81%) of the desired product. MS (DCI) m/e 317 (M+H)+, 334 (M+NH4)+; 1H NMR (500 MHz, DMSO-d6) δ 9.88 (s, 1H), 8.03 (s, 1H), 7.68 (d, J=8.7 Hz, 1H), 7.06 (d, J=2.2 Hz, 1H), 6.91-6.93 (m, 2H), 6.86-6.87 (m, 2H), 3.60 (s, 3H), 3.54 (s, 2H).

Provenance & Evidence