Sodium ethoxide → HCID 12044968, compound

Participants

Reaction Conditions

Reaction Steps

A solution of tert-butyl 6-(3-bromo-5-cyano-1-methyl-1H-pyrrol-2-yl)-4,4-dimethyl-2-oxo-2H-3,1-benzoxazine-1(4H)-carboxylate (1 eq, 0.4 g, 0.87 mmol) in THF was added to a solution of sodium ethoxide (3 eq, 0.18 g, 2.6 mmol) in ethanol (10 mL). The solution was heated at 80° C. for 1 h then cooled to room temperature and concentrated in vacuo. The residue was dissolved in THF (10 mL) and 4N HCl (10 mL) was added. After heating to 60° C. for 16 h the solution was cooled, poured into water and the layers were separated. The aqueous layer was extracted with ethyl acetate (3×10 mL) and the combined organic layer was washed with brine, dried over MgSO4 and concentrated in vacuo. The product, 4-bromo-5-(4,4-dimethyl-2-oxo-1,4-dihydro-2H-3,1-benzoxazin-6-yl)-1-methyl-1H-pyrrole-2-carbonitrile (0.17 g, 54%) was obtained by crystallization from 20% ethyl acetate/hexane. 1H NMR (300 MHz, d6-DMSO) δ 1.64 (s, 6H), 3.62 (s, 3H), 7.02 (d, 1H, J=8.2 Hz), 7.34 (s, 1H), 7.35 (dd, 1H, J=1.3, 8.2 Hz), 7.40 (s, 1H), 10.47 (s, 1H). MS (ESI (−)) m/z 358/360 (M−H)−. Anal. calcd for C16H14N3O2Br, C, 53.4, H, 3.92, N, 11.7. Found, C, 52.6, H, 3.82, N, 11.2.

Provenance & Evidence