Cesium carbonate → 1,1-Dimethylethyl (2-bromo-1,3-thiazol-5-yl)((2S)-2-((((1,1-dimethylethyl)oxy)carbonyl)amino)-3-(4-(trifluoromethyl)phenyl)propyl)-carbamate

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Reaction Conditions

Reaction Steps

To a 250 mL round-bottomed flask was added tert-butyl 2-bromothiazol-5-ylcarbamate (0.75 g, 2.69 mmol), DMF (26.9 mL, 2.69 mmol), and cesium carbonate (1.75 g, 5.37 mmol). The mixture was warmed to 50° C. and 1,1-dimethylethyl 4-((4-(trifluoromethyl)phenyl)methyl)-1,2,3-oxathiazolidine-3-carboxylate 2,2-dioxide (1.13 g, 2.96 mmol, Scheme 1) was added slowly in 10 mL DMF. After 1 hour, the mixture was cooled, diluted with ether (100 mL) and washed with brine (3×50 mL). The organic layer was dried over sodium sulfate, evaporated onto a plug of silica gel and purified by chromatography through a Redi-Sep® pre-packed silica gel column (40 g), eluting with a gradient of 20% to 100% EtOAc in hexane, to provide the product (1.42 g, 91% yield) as a white amorphous solid. LCMS (API-ES) m/z (%): 582 (100%, M+H).

Provenance & Evidence