Sodium Carbonate → N-[1-(5-Bromo-2-fluoro-phenyl)-2,2-difluoro-1-hydroxymethyl-ethyl]-2-chloropropionamide

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Reaction Steps

[1-(5-Bromo-2-fluoro-phenyl)-2,2-difluoro-1-hydroxymethyl-ethyl]-carbamic acid tert-butyl ester [Example 42 step c)] (2.21 g, 5.75 mmol) was dissolved in 20 mL HCl solution 4 mol/L in dioxane and stirred at room temperature for 60 minutes. The reaction mixture was evaporated to give a white solid which was directly taken up in 15 mL dichloromethane. 20 mL aqueous Na2CO3 solution (10% w/w) was added and the emulsion was cooled to 0-5° C. Racemic 2-chloro-propionyl chloride (787 mg, 6.20 mmol) was added dropwise and the reaction mixture was slowly warmed to room temperature. After 30 minutes, the layers were separated and washed with dichloromethane. The organic layers were combined, dried over Na2SO4 and evaporated. The crude product was purified on a silica gel column by eluting with heptanes/EtOAc 3/1->2/1 to give 632 mg of the first eluting and 619 mg of the second eluting diastereomer.

Provenance & Evidence