Dimethylformamide → 2-(2-Chloroethyl)-2,3-dihydro-2,4-dimethylpyrido[3,2-f]-1,4-oxazepin-5(4H)-one hydrochloride

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Reaktionsschritte

To a suspension of 60 g (60% in oil, 1.5 mole) of sodium hydride in 400 ml of tetrahydrofuran heated to reflux was added a solution of 100 g (0.70 mole) of 2-chloronicotinic acid and 80 g (0.70 mole) of 1,3-dimethyl-3-pyrrolidinol so as to maintain good reflux. Heating at reflux was continued overnight. The mass spectra showed very little product at this point; therefore, 400 ml of dimethylformamide was added and heating at 77° C. was continued overnight. Approximately 10% of the desired product was then observed by mass spectra. The tetrahydrofuran was evaporated by passing nitrogen gas over the reaction mixture while at the same time being replaced with dimethylformamide. The temperature was concomitantly increased to 100° C. The mixture was stirred overnight at 100° C. After cooling, no salt precipitated out; therefore, dimethylformamide was removed by rotary evaporation (90° C.; 5 mm). Approximately 250 g of crude salt was collected. Into a suspension of 230 g (~0.88 mole) of this crude salt in 1 liter of chloroform was bubbled hydrogen chloride gas to pH 6 . To this suspension was added 463 g (l.77 mole) of triphenyl phosphine and 463 g of carbon tetrachloride. The mixture was then heated to reflux. After 8 minutes a vigorous exotherm ensued which subsided in 30 minutes. Reflux was continued for 2.5 hr. According to infrared analysis, the reaction was near completion. Approximately 40 ml of triethylamine was added to drive the reaction to completion. The mixture was left standing overnight at room temperature.

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