Thionyl Chloride → HCID 21454865, compound

Participants

Reaction Conditions

Reaction Steps

Thionyl chloride (8.7 g.) is added to a solution of (5,6-dihydro-1,4-dithiin-2-yl)acetic acid (6.45 g.) in benzene (120 cc.). The mixture is heated under reflux until gas ceases to be evolved and is then concentrated to dryness under reduced pressure (20 mm.Hg). The brown oil thus obtained is dissolved in acetone (50 cc.) and the resulting solution is added dropwise, over the course of one hour, to a solution of 7-amino-2-carboxy-3-[(1-methyl-1,2,3,4-tetrazol-5-yl)thiomethyl]-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene (12 g.) and sodium bicarbonate (7.35 g.) in water (200 cc.) and acetone (100 cc.) kept at 3° C. Stirring is continued for a further hour at 3° C. and then for 2 hours at about 20° C. The mixture is concentrated to dryness under reduced pressure (20 mm.Hg), water (150 cc.) is added and the slight amount of insoluble matter is filtered off. The solution is washed twice with ethyl acetate (300 cc.) and brought to pH 2.2 by addition of 4 N hydrochloric acid in the presence of ethyl acetate (300 cc.). The solution is filtered through "Supercel" and decanted, and the aqueous phase is extracted with ethyl acetate (300 cc.). The organic phases are combined and washed with water (200 cc.), dried over magnesium sulphate and treated with decolourizing charcoal. The mixture is filtered and the filtrate is concentrated to a volume of 100 cc. Diethyl ether (700 cc.) is then added and the mixture is cooled to about 0° C.; the resulting precipitate is filtered off and washed with diethyl ether (100 cc.). 2-Carboxy-7-[(5,6-dihydro-1,4-dithiin-2-yl)-acetamido]-3-[(1-methyl-1,2,3,4-tetrazol-5-yl)thiomethyl]-8-oxo-5-thia-1-aza-bicyclo[4,2,0]oct-2-ene (4.4 g.) is obtained in the form of a cream powder.

Provenance & Evidence