Triethylamine → HCID 22811194, compound

Temperature

0 °C

Methyl 4-(4-chloro-2-oxoazetidin-1-yl)-3-oxobutyrate (1.1 g, 5 mmole) was dissolved in a mixture of diethyl ether (20 ml) and methylene dichloride (30 ml). The solution was stirred at -30° C. with exclusion of moisture while triethylamine (510 mg, 5 mmole) in diethyl ether (5 ml) was added dropwise over 3 minutes. The mixture was then warmed to 0° C. and stirred for a further 40 minutes. The mixture was diluted with ethyl acetate (100 ml) and the solution was washed twice with 5% sodium chloride solution. The solution was dried (magnesium sulphate) and the solvent was evaporated to yield a yellow gum (350 mg). The gum was chromatographed on silica gel (30 g) using ethyl acetate/petroleum ether to give, in order of elution, (Z)-carbmethoxychloromethylene-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (5 mg), (E)-carbmethoxymethylene-4-oxa-1-azabicyclo[3.2.0]heptan-7-one (73 mg) and (Z)-carbmethoxymethylene-4-oxa- 1-azabicyclo[3.2.0]heptan-7-one (65 mg). The latter compound was obtained as colourless prisms, m.p. 168°-169° C., from ethyl acetate/petroleum ether (b.p. 60°-80° C.). (Found: M+, 183.05334. C8H9NO4 requires 183.05315).

1. additionwas added dropwise over 3 minutes
2. washthe solution was washed twice with 5% sodium chloride solution
3. dry with materialThe solution was dried (magnesium sulphate)
4. customthe solvent was evaporated

ORD record

ord-091e9dee003b4c98aa6f8fd7fc83261a

Source dataset

uspto-grants-1980_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US04206120