Methanethioamide → HCID 13175941, compound

Participants

Reaction Conditions

Reaction Steps

A solution of 2-benzhydryloxycarbonyl-3-(1-bromo-2-oxoethyl)-7-t-butoxycarbonylamino-8-oxo-5-thia-1-azabicyclo[4.2.0]oct-2-ene (mixture of the epimeric bromoaldehydes) (2.34 g) and thioformamide (0.3 g) in dry tetrahydrofuran (23 cc) is stirred for 3 hours at 20° and then heated for 90 minutes at 50° C. The reaction mixture is diluted with ethyl acetate (160 cc) and washed with a saturated solution of sodium bicarbonate (100 cc) and then with a semi-saturated solution of sodium chloride (100 cc). After drying of the organic layer over magnesium sulphate and evaporation of the solvent under reduced pressure (30 mm Hg; 4 kPa) at 30° C., the residue obtained is subjected to chromatography on a column (height: 30 cm; diameter: 2.5 cm) of silica gel (0.04-0.06 mm), elution being carried out under a pressure of 0.8 bar (80 kPa) with a 70/30 (by volume) mixture of cyclohexane and ethyl acetate, and 50 cc fractions being collected. Fractions 16 to 25, containing the pure product, are combined and concentrated to dryness under reduced pressure (30 mm Hg; 4 kPa) at 30° C., and the residue is triturated in isopropyl ether (50 cc). After filtration and drying, 2-benzhydryloxycarbonyl-7-t-butoxycarbonylamino-8-oxo-3-(thiazol-5-yl)-5-thia-1-azabicyclo[4.2.0]oct-2-ene (0.85 g) is obtained in the form of a cream-coloured solid.

Provenance & Evidence