2(3H)-Benzoxazolone → 2(3H)-Benzoxazolone, 3-(3-chloropropyl)-

Participants

Reaction Steps

To a stirred suspension of sodium hydride (7.8 g, 160 mmol, ether-washed) in dimethylformamide (75 ml) was added dropwise under nitrogen, 2-benzoxazolinone (20.0 g, 150 mmol) dissolved in dimethylformamide (150 ml). After complete addition the reaction was stirred at ambient temperature for 30 min, and then it was cooled to -5° C. with an ice-acetone bath. A solution of 3-chloro-1-bromopropane (46.6 g, 300 mmol) in dimethylformamide (50 ml) was added dropwise (temperature never exceeded 0° C.). The reaction was allowed to reach ambient temperature and was stirred for 16 hours. The reaction was poured into waiter, and the aqueous mixture was extracted with ethyl acetate. The ethyl acetate was washed with water, dried (MgSO4), and the extract concentrated to afford 21.9 g of a brown solid. The solid was recrystallized from toluene-hexane to afford N-(3-4chloropropyl)-2-benzoxazolinone as large needles, 15.6 g, m.p.=264°-266° C.

Provenance & Evidence