[H-].[Na+].[CH3:3][CH:4]1[NH:10][C:9](=[O:11])[CH2:8][CH2:7][CH2:6][CH2:5]1.[CH2:12](Br)[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1>C1COCC1.O>[CH2:12]([N:10]1[CH:4]([CH3:3])[CH2:5][CH2:6][CH2:7][CH2:8][C:9]1=[O:11])[C:13]1[CH:18]=[CH:17][CH:16]=[CH:15][CH:14]=1Sodium hydride (95%, 1.74 g, 68.7 mmol, 1.15 equiv) was added to a solution of 7-methylazepan-2-one (2-2, 7.60 g, 59.8 mmol, 1 equiv) in THF (150 mL) at 0° C. and the resulting mixture was warmed to 23° C. and stirred for 20 h. Benzyl bromide (7.82 mL, 65.7 mmol, 1.10 equiv) was added followed by 2 drops of water, and the resulting mixture was stirred at 23° C. for 20 h. Excess sodium hydride was quenched carefully with water and the mixture was concentrated. The residue was partitioned between water and dichloromethane. The organic layer was dried over sodium sulfate and concentrated. The residue was purified by flash column chromatography (100% hexanes initially, grading to 100% EtOAc) to give 1-benzyl-7-methylazepan-2-one (2-3) as a colorless oil. LRMS m/z (M+H) 218.2 found, 218.2 required.
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