1,3-Propanediamine, N'-(ethylcarbonimidoyl)-N,N-dimethyl-, monohydrochloride → (R)-3-(3-fluoro-4-trifluoromethoxy-benzylcarbamoyl)-4-(4-trifluoromethoxy-benzenesulfonyl)-piperazine-1-carboxylic acid tert-butyl ester

Participants

Reaction Steps

To a solution of the compound (1.35 g) obtained in Example 783, Step 2 in chloroform (15 ml) were added 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride (625 mg), 1-hydroxybenzotriazole hydrate (499 mg) and 3-fluoro-4-trifluoromethoxybenzylamine (620 mg) with stirring under ice-cooling. After stirring overnight at room temperature, the reaction mixture was partitioned by adding saturated aqueous sodium hydrogen carbonate solution and chloroform, and the aqueous layer was re-extracted twice with chloroform. The organic layers were combined, dried over anhydrous magnesium sulfate, filtrated, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (hexane:ethyl acetate=1:l) to give the title compound (1.50 g).

Provenance & Evidence