Ammonium Chloride → HCID 10899598, compound

Temperature

0 °C

In an atmosphere of argon gas, a solution of (4S,5S)-5-methoxycarbonyl-4-(oxazolidin-2-on-3-yl)carbonyl-1-cyclohexene (8.50 g, 33.6 mmoles) disclosed in literature [N. Narasaka et al, J. Am. Chem. Soc., 111, 5340 (1989)] in methanol (50 ml) was added to 1M dimethoxymagnesium/methanol (168 ml, 168 mmoles), and the mixture was stirred at 0° C. for 15 minutes. Saturated aqueous solution of ammonium chloride was added to the reaction mixture, and the resulting mixture was extracted with toluene. The toluene extract solution was washed with saturated aqueous solution of sodium chloride and then the solvent was distilled off under reduced pressure. The residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:9, v/v) to obtain (4S,5S)-4,5-bis(methoxycarbonyl)-1-cyclohexene (1.89 g, Yield 30%).

1. extractionthe resulting mixture was extracted with toluene
2. extractionThe toluene extract solution
3. washwas washed with saturated aqueous solution of sodium chloride
4. distillationthe solvent was distilled off under reduced pressure
5. customThe residue was purified by silica gel column chromatography (ethyl acetate:n-hexane=1:9, v/v)

ORD record

ord-d0c96da970834197b875db6cba381386

Source dataset

uspto-grants-1994_12

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05374625