Dimethylformamide → HCID 131717474, compound

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Reaction Steps

To a solution of N,N-dimethylformamide (0.321 ml; 1 Eq.) in dichloromethane (20 ml) keeping at -10° C. is added dropwise oxalyl chloride (0.354 ml; 1.64 Eq.), and the mixture is stirred at -10° to -5° C. for 15 minutes. To this mixture are added a solution of 2-(2-t-butoxycarbonylamino-4-thiazolyl)-2-triphenylmethoxyiminoacetic acid (2.0 g; 09 Eq.) in dichloromethane (10 ml) and N-methylmorpholine (0.502 ml; 1.1 Eq.), and the mixture is stirred at -10° to -5° C. for 30 minutes. To this solution is added a solution of 7β-amino-3-chloromethyl-3-cephem-4-carboxylic acid p-toluenesulfonate (2.4 g; 4.16 mMol.). To this mixture is added N-methylmorpholine (0.502 ml; 1 Eq.), and the mixture is stirred at -10° to -5° C. for 45 minutes. The reaction mixture is diluted with ice water and extracted with dichloromethane. The extract is washed with hydrochloric acid, aqueous sodium hydrogen carbonate, and water, dried, and concentrated in vacuum. The residue is purified by silica gel chromatography (toluene:ethyl acetate) to give 7β-[2-(2-t-butoxycarbonylamino-4-thiazolyl)-2-trityloxyimino-acetamido]-3-chloromethyl-3-cephem-4-carboxylic acid p-methoxybenzyl ester (2) (2.38 g).

Provenance & Evidence