Sodium hydride → 6-bromo-1-{[2-(trimethylsilyl)ethoxy]methyl}-1,4-dihydro-2H-3,1-benzoxazin-2-one

Beteiligte Stoffe

Reaktionsschritte

To a solution of sodium hydride (55 wt % in mineral oil, 1.36 g, 31.2 mmol) in N,N-dimethylformamide (37 ml) was added 6-bromo-1,4-dihydro-2H-3,1-benzoxazin-2-one (5.93 g, 26.0 mmol) in N,N-dimethylformamide (37 ml) at 0° C. The mixture was stirred at room temperature for one hour, then 2-(chloromethoxy)ethyltrimethylsilane (4.77 g, 28.6 mmol) was added at 0° C. The mixture was stirred at room temperature overnight. The mixture was partitioned between water and ethyl acetate. The organic layer was washed with water (four times), dried over sodium sulfate, and concentrated in vacuo. The residue was purified by silica gel column chromatography (eluent; hexane/ethyl acetate=90/10 to 60/40) to afford 6-bromo-1-{[2-(trimethylsilyl)ethoxy]methyl}-1,4-dihydro-2H-3,1-benzoxazin-2-one as a pale yellow solid (7.96 g, 22.2 mmol, 85%).

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