Sodium Chloride → Hydrochloric Acid

Participants

Reaction Conditions

Reaction Steps

Diphenylmethyl 7-phenylacetamido-3-(tetrahydropyran-4-yl)thio-3-cephem-4-carboxylate (1.28 g) was dissolved in dichloromethane (15 ml) and the solution was cooled to -20° C. To the solution, pyridine (0.52 ml) and phosphorus pentachloride (665 mg) were added and the resulting mixture was stirred under ice-cooling for 2 hours and then further cooled to -30° C. Anhydrous methanol (1.72 ml) was rapidly added to the cooled reaction solution while maintaining the temperature below 0° C. and the mixture was stirred under ice-cooling for 3 hours and then further cooled again to -20° C. After adding a 15% aqueous sodium chloride solution to the reaction solution, the pH thereof was adjusted to 1 with the addition of aqueous sodium hydrogen carbonate and the reaction solution was further stirred for 30 minutes. Upon subsequent addition of diisopropylether (30 ml), precipitate was deposited from the solution, taken up by filtration, washed with cold water and with diisopropylether successively and then dried to yield the titled compound in the form of hydrochloride (970 mg; 87%).

Provenance & Evidence