Dimethylformamide → 4-{4-[4-(4-Trifluoromethyl-phenyl)-piperazin-1-yl]-butyrylamino}-piperidine-1-carboxylic acid tert-butyl ester

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Reaction Steps

4-[4-(4-Trifluoromethyl-phenyl)-piperazin-1-yl]-butyric acid lithium salt (425 mg; 1.32 mmol, prepared in accordance with Example 3) and tetramethyl-O-(1H-benzotriazol-1-yl)uronium hexafluorophosphate (500 mg; 1.32 mmol) are diluted in a 5 to 1 mixture of dimethylformamide and tetrahydrofuran (6 mL) and the resulting solution is stirred for 5 minutes. 4-Amino-piperidine-1-carboxylic acid tert-butyl ester (264 mg; 1.32 mmol, free base of Example 73) and diisopropylethyl amine (460 μL; 2.64 mmol) are added and the reaction is then stirred for 90 minutes at room temperature. Following dilution with ethylacetate (30 mL), the organic layer is washed with aq. sat. sodium hydrogen carbonate (3×10 mL), is dried over magnesium sulfate and concentrated under reduced pressure to afford the desired product (660 mg; 1.32 mmol).

Provenance & Evidence