p-Toluenesulfonic acid → HCID 10437193, compound

Participants

Reaction Steps

The product from Example 4A (218 mg, 0.34 mmol) in absolute ethanol was treated with three crystals of p-toluenesulfonic acid and heated at reflux. After 3 hours, the mixture was allowed to cool to room temperature and was concentrated under reduced pressure. The residue was taken up in ethyl acetate, washed with saturated NaHCO3 solution, brine, dried (Na2SO4), filtered, and the filtrate was concentrated under reduced pressure. The residue was purified by flash chromatography (85% ethyl acetate/hexanes) to provide the title compound as a yellow solid (36 mg, 20% yield). 1H NMR (300 MHz, DMSO-d6) δ 9.41 (d, 2H), 8.78 (bs, 2H), 8.63 (bs, 1H), 8.28 (d, 1H), 8.02-8.1 (m, 2H), 7.81 (dd, 1H), 7.70 (dd, 1H), 6.91-7.01 (m, 2H), 6.49-6.61 (m, 4H), 6.33-6.42 (m, 2H); MS (ESI) 535 (M−H)−.

Provenance & Evidence