Cesium carbonate → HCID 86604640, compound

Participants

Reaction Steps

To a stirred solution of tert-butyl [(2R,3S)-4-oxo-2-phenyl-2,3,4,5-tetrahydro-1,5-benzoxazepin-3-yl]carbamate (67a) (190 mg, 0.536 mmol) in dry DMF (2 mL) under nitrogen was added (bromomethyl)cyclopropane (108 mg, 0.800 mmol) and powdered cesium carbonate (264 mg, 0.810 mmol). The mixture was stirred overnight at ambient temperature then diluted with ewater and extracted with ethyl acetate three times. The residue from the combined organic extracts was purified by flash chromatography on silica gel eluting with 6:1 (v/v) hexane:ethyl acetate to afford the title compound (201 mg, 92%) as a white solid. TLC Rf=0.31 (6:1 hexane:ethyl acetate). 1H NMR (300 MHz, CDCl3) δ0.19 (m, 1H), 0.35-0.62 (m, 3H), 1.15 (m, 1H), 1.37 (s, 9H), 3.50 and 3.55 (dd, 1H, J=7.0 Hz), 4.12 and 4.17 (dd, 1H, J=7.0 Hz), 4.93 (m, 2H), 5.65 (d, 1H, J=7.0 Hz), 7.29 (m, 4H), 7.41 (m, 5H). MS APCI, m/z=309 (M-BOC). LC/MS: 3.08 min.

Provenance & Evidence