Methanol → HCID 67908810, compound

Participants

Reaction Steps

A stirred solution of diphenylmethyl 3-(2,5-dihydro-2-oxofuran-4-ylmethylthio) -7β-phenylacetamidoceph-3-em-4-carboxylate (520 mg) in dry dichloromethane (8 ml) was cooled to -20° C., then N-methylmorpholine (0.202 ml) was added followed by a solution of phosphorous pentachloride in dichloromethane (7.2 ml of a solution containing 40 mg ml-1). The solution was stirred at -15° to -20° C. for 30 mins., then methanol (1.8 ml) was added and the mixture stirred at room temperature for 30 mins. Water (2.5 ml) was then added and the mixture vigorously stirred for a further 30 mins. The dichloromethane was then evaporated on a rotary evaporator and the residue partitioned between ethyl acetate and water. The pH of the aqueous phase was adjusted to 6.0 with saturated sodium bicarbonate solution and the organic phase was separated, washed with water, then brine, dried over magnesium sulphate and evaporated. The title compound (333 mg) was isolated by column chromatography of the residue (Kieselgel, ethyl acetate as eluent). υmax (CHCl3) 1780 and 1750 cm-1 ; δH (CDCl3) 1.86 (2H, broad s), 3.42 (1H, d, J 17.4Hz), 3.48 (1H, d, J 15.0Hz), 3.60 (1H, d, J 17.4Hz), 3.65 (1H, d, J 15.0Hz), 4.60 (2H, s), 4.78 (1H, d, J 5.1Hz), 4.95 (1H, d, J 5.1Hz), 5.89 (1H, s), 6.99 (1H, s), 7.2-7.5 (10H, m).

Provenance & Evidence