Hexamethylphosphoramide → Ethyl 4-oxooxane-3-carboxylate

Participants

Reaction Conditions

Reaction Steps

Lithium diisopropylamide (1.14 mol/l solution in n-hexane/tetrahydrofuran, 2.5 ml) was added dropwise to a solution of tetrahydro-4H-pyran-4-one (260 mg) in tetrahydrofuran (13 ml) at −78° C., and the mixture was stirred for one hour while warming to 0° C. The reaction solution was cooled to −78° C. again, hexamethylphosphoric triamide (452 μl) was added and subsequently ethyl cyanoformate (280 μl) was added at the same temperature. The mixture was stirred over one hour while warming to 0° C. The reaction solution was separated by adding distilled water and ethyl acetate. The resulting organic layer was washed with brine and dried over anhydrous sodium sulfate. The solvent was evaporated under reduced pressure. The resulting residue was purified by silica gel column chromatography (developed with ethyl acetate-hexane) to give the title compound (210 mg).

Provenance & Evidence