4-Chlorobutyryl chloride → 4-chloro-N-methoxy-N-methylbutyramide

Participants

Reaction Steps

To a solution of 4-chlorobutyryl chloride (10.0 g in 200 mL of dry methylene chloride) was added 10.4 g of N,O-dimethylhydroxylamine hydrochloride. The mixture was stirred under nitrogen and maintained below 25° C. by cooling in an ice bath as necessary while triethylamine (29.1 mL) was added dropwise over about 20 minutes, resulting in precipitation. After 1.5 hours at room temperature, the mixture was concentrated in vacuo. The residue was partitioned between 100 mL of diethyl ether and 100 mL of saturated aqueous sodium bicarbonate solution. The organic layer was washed with an additional 100 mL of saturated sodium bicarbonate, and the aqueous fractions were back-extracted with ether. The combined organic phases were dried over sodium sulfate, filtered, and concentrated in vacuo to give 10.5 g (90%) of an oil, which had satisfactory purity by 1H NMR (CDCl3). Mass spectrum (PB-NH3 /CI): m/e=166 (M+H).

Provenance & Evidence