反应详情

温度

50 °C

Acetic anhydride (1.00 mL, 10.6 mmol;) was added to a solution of 2-Nitro-6,7,8,9-tetrahydro-5-oxa-9-aza-benzocycloheptene (0.580 g, 2.99 mmol), 4-Dimethylaminopyridine (20 mg, 0.1 mmol; Acros) and Triethylamine (1.0 mL, 7.2 mmol) in Acetonitrile (10 mL; Acros). The reaction was stirred under an atmosphere of Nitrogen overnight. Conversion was moderate, so the mixture was heated at 50° C. for the weekend. The solution was conc. in vacuo, diluted with 25 mL EtOAc then washed with 1N HCl (10 mL), satd. sodium bicarbonate (10 mL) and brine (10 mL). After drying over sodium sulfate, the solution was conc. and the residue chromatographed (ISCO, 80 g SiO2, 0-65% EtOAc:Hex) to afford 1-(2-Nitro-7,8-dihydro-6H-5-oxa-9-aza-benzocyclohepten-9-yl)-ethanone as light yellow solids (522 mg, 74%). Mixture of rotamers in 1H-NMR, resulting in very broad signals for the aliphatic methylenes. 13C-NMR (CDCl3): 169.8, 160.3, 142.7, 134.3, 124.8, 124.6, 122.6, 71.1, 45.0, 28.0, 22.4

1. washthen washed with 1N HCl (10 mL)
2. dry with materialAfter drying over sodium sulfate
3. customthe residue chromatographed (ISCO, 80 g SiO2, 0-65% EtOAc:Hex)