Trityl chloride → (Z)-alpha-((2-(tert-Butoxy)-1,1-dimethyl-2-oxoethoxy)imino)-2-(tritylamino)thiazol-4-acetic acid

Participants

Reaction Conditions

Reaction Steps

To a suspension of (Z)-2-(2-aminothiazol-4-yl)-2-(2-tert-butoxycarbonylprop-2-oxyimino) acetic acid (monoblocked acid) (100 g) prepared as in Example 1 in methylene chloride (1.74 lt) is added triethylamine (33.76 g) slowly at 5-10° to obtain a clear solution. Add triphenylchloromethane (118.5 g) at 5-10° and then mass temperature is raised to 36-38°. The resulting reaction mixture is stirred for 6 hours. It is then cooled to 20-25° and washed with DM water. The organic layer is concentrated and toluene is added to the residue. The resulting slurry is cooled to 20-25° C., the product is filtered, washed with toluene and dried under reduced pressure at 40-45° C. Yield 171 g (98.5% of theory), water <0.2% w/w, assay 96-97% w/w, methylene chloride 2-2.5% w/w and toluene 1-2% w/w.

Provenance & Evidence