Hydrochloric Acid → N-Hydroxy-N-methyl-3-(4-methylphenyl)prop-2-enamide

Temperature

0 °C

A solution of 4-methylcinnamic acid (1.62 g, 10 mmol) and oxalyl chloride (2.0 ml, 23 mmol) in 50 ml anhydrous tetrahydrofuran (THF) was stirred at reflux for two hours, then concentrated in vacuo. The residue was redissolved in 30 ml THF, and added dropwise to a solution of N-methyl-hydroxylamine hydrochloride (1.26 g, 15 mmol) and triethylamine (5.0 ml, 36 mmol) in 50 ml of 2:1 THF-water at 0° C. The mixture was stirred for one hour at 0° C., then for one hour at room temperature, and then poured into excess 5% aqueous hydrochloric acid. The resulting mixture was extracted with ethyl ether, and the ether extract washed successively with 5% aqueous hydrochloric acid and brine, dried over sodium sulfate, and evaporated. Recrystallization of the residue from ethyl acetate provided 1.48 g (77% yield) of the titled compound, mp 142°-144° C.

1. temperatureat reflux for two hours
2. concentrationconcentrated in vacuo
3. dissolutionThe residue was redissolved in 30 ml THF
4. waitfor one hour at room temperature
5. extractionThe resulting mixture was extracted with ethyl ether
6. extractionthe ether extract
7. washwashed successively with 5% aqueous hydrochloric acid and brine
8. dry with materialdried over sodium sulfate
9. customevaporated
10. customRecrystallization of the residue from ethyl acetate

ORD record

ord-9b3f8450499b475581a2d38baa89c455

Source dataset

uspto-grants-1989_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04820828