Potassium Permanganate → HCID 69109367, compound

Participants

Reaction Conditions

Reaction Steps

Benzyl ester 3 (4.6 g, 9.7 mmol) was dissolved in THF (100 mL) and the solution stirred at 70° C. Potassium permanganate (7.7 g, 48.5 mmol) dissolved in water (125 mL) was added slowly through a dropping funnel over a period of 2 hours. After addition was complete, reaction mixture was stirred at 70° C. for 30 min and cooled to room temperature. The brown precipitate was filtered over a Celite® bed and the filtrate was concentrated under reduced pressure. The residual oil was taken up in EtOAc (100 mL) and acidified with 2.0 M HCl. The organic layer was separated and washed with water (1×100 mL) and brine (1×100 mL), dried, and concentrated under reduced pressure to yield the desired acid compound 4 (4.5 g, 94%). 1H NMR (DMSO-d6): 12.7 (br, 1H), 7.91 (d, J=8.8 Hz, 2H), 7.42 (d, J=8.4 Hz), 7.30-7.37 (m, 7H), 7.03 (d, J=8.8 Hz, 2H), 6.97 (d, J=8.8 Hz, 2H), 5.12 (s, 2H), 4.24-4.28 (m, 1H), 3.04 (dd, J=13.6 and 5.2 Hz, 1H), 2.91 (dd, J=13.6 and 9.6 Hz, 1H), 1.33 (s, 9H).

Provenance & Evidence