Hydrogen Peroxide → HCID 60206841, compound

Participants

Reaction Steps

To a solution of tert-butyl (4S)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-3,4-dihydro-2H-chromen-4-ylcarbamate (1.09 g, 2.90 mmol) in tetrahydrofuran (10 mL) was added sodium hydroxide (6 mL, 1 N, 6 mmol) followed by hydrogen peroxide (10 mL, 30%). The reaction mixture was stirred at room temperature for 2 h and then quenched with sodium hydrogen sulfite (5 g in 10 mL of water). The mixture was adjusted to pH 4 with 2 N sodium hydroxide and then extracted with ethyl acetate (3×50 mL). The combined extracts were washed with saturated sodium chloride, dried (sodium sulfate), filtered, and concentrated under reduced pressure. Flash chromatography (silica gel, 10–25% ethyl acetate/hexanes) provided (650 mg, 85%) of the desired product. 1H NMR (300 MHz, CDCl3) δ 7.89 (s, 1H), 6.75 (d, J=2.7 Hz, 1H), 6.72–6.63 (m, 1H), 5.03 (d, J=7.5 Hz, 1H), 4.77–4.75 (m, 1H), 4.16–4.08 (m, 2H), 2.30 (s, 1H), 2.16–2.13 (m, 1H), 2.05–1.99 (m, 1H), 1.47 (s, 9H).

Provenance & Evidence