Pyridine → HCID 67899263, compound

Participants

Reaction Conditions

Reaction Steps

6.4 (12.2 mmol) of benzhydryl 7-phenylacetamido-3-[(Z)-propen-1-yl]-3-cephem-4-carboxylate (Example 9) are dissolved in 64 ml of methylene chloride, the solution is cooled to -40° C. with a dry ice bath and 2.47 ml (30.5 mmol) of pyridine and 2.54 g (12.2 mmol) of phosphorus pentachloride are added in succession. After 5 minutes, the mixture is allowed to warm to -20° C., after which the temperature should rise to -10° C. in the course of 20 minutes and then rise to +10° C. The solution is now stirred at +10° C. to +15° C. for 1 hour. The mixture is subsequently cooled to -40° C., 100 ml of methanol (-30° C.) are added and the mixture is stirred at +10° C. for a further 30 minutes. The reaction solution is concentrated gently, the oil obtained is dissolved in 600 ml of methylene chloride, the solution is stirred into 800 ml of sodium bicarbonate solution and the mixture is stirred for 10 minutes. The methylene chloride phase is separated off, washed once with water and dried over sodium sulphate. The methylene chloride filtrate is chromatographed on 400 ml of silica gel (0.04-0.063 mm), elution being carried out first with methylene chloride and then with methylene chloride with the addition of methanol (gradient up to 10%). The eluate is investigated by means of analytical HPLC and TLC (thin layer chromatography) (methylene chloride/methanol=100:1).

Provenance & Evidence