反应详情

An activated acid, prepared from ethyl hydrogen α-(cyclopropyloxyimino)malonate (syn isomer)(19.78 g), phosphorus oxychloride (11.9 ml) and N,N-dimethylformamide (9.91 ml) by a conventional manner, was added to a saturated ammonia solution in tetrahydrofuran at -30° C. The mixture was gently warmed to ambient temperature. The mixture was poured into a mixture of ethyl acetate (1 l) and ice-water (1 l) and adjusted to pH 7 with saturated aqueous solution of sodium bicarbonate. The organic layer was separated washed with saturated aqueous solution of sodium chloride, dried over magnesium sulfate and concentrated in vacuo. The residue was subjected to column chromatography on silica gel (200 g) using chloroform as an eluent to give ethyl 2-carbamoyl-2-(cyclopropyloxyimino)acetate (syn isomer) as a crystal (10.51 g).

1. customThe organic layer was separated
2. washwashed with saturated aqueous solution of sodium chloride
3. dry with materialdried over magnesium sulfate
4. concentrationconcentrated in vacuo