Sodium hydride → Tert-butyl 3-oxa-7-azabicyclo[4.1.0]heptane-7-carboxylate
Reaction equation
[C:1]([O:5][C:6](=[O:15])[NH:7][C@H:8]1[C@H:13](Br)[CH2:12][CH2:11][O:10][CH2:9]1)([CH3:4])([CH3:3])[CH3:2].[H-].[Na+]>CN(C)C=O>[C:1]([O:5][C:6]([N:7]1[CH:8]2[CH:13]1[CH2:12][CH2:11][O:10][CH2:9]2)=[O:15])([CH3:4])([CH3:3])[CH3:2]Participants
4
Procedure
trans-(4-Bromo-tetrahydro-pyran-3-yl)-carbamic acid tert-butyl ester (intermediate D) (1.0 g, 3.5 mmol) was dissolved in 35 mL dimethylformamide. Sodium hydride (60%, 214 mg, 5.4 mmol) was added at 0° O. The reaction mixture was stirred at room temperature for 2 h. The reaction mixture was quenched by careful addition of water. The mixture was extracted three times with diethylether. The combined organic phases were dried on sodium sulfate, filtered and evaporated. Purification of the residue by flash chromatography on silica gel (heptane/ethyl acetate 1:0→1:1) yielded the title compound as a colorless oil (499 mg, 70%), MS: m/e=143 [(M-buten)+].