Diisopropylethylamine → [(S)-1-[1-(2-hydroxy-2-methyl-propyl)-1H-pyrazol-3-ylcarbamoyl]-2-(tetrahydro-pyran-2-yl)-ethyl]-carbamic acid t-butyl ester

Participants

Reaction Conditions

Reaction Steps

To a solution of (S)-2-t-butoxycarbonylamino-3-(tetrahydro-pyran-2-yl)-propionic acid (700 mg, 2.56 mmol) in N,N-dimethylformamide (6 mL) was added 1-(3-amino-pyrazol-1-yl)-2-methyl-propan-2-ol (prepared in U.S. Pat. Appl. US2008021032 Example 80, 398 mg, 2.57 mmol) and benzotriazol-1-yl-oxy-tris(dimethylamino)phosphonium hexafluorophosphate (1.36 g, 3.0 mmol). The mixture was stirred at 0° C. and N,N-diisopropylethylamine (0.4 mL) was added. The mixture was stirred at room temperature overnight and solvents were evaporated. The residue was treated with ethyl acetate and ammonium chloride solution, and the organic layer separated. The organic layer was washed with saturated sodium chloride solution and dried over sodium sulfate. Solvents were evaporated and the residue was purified through flash column chromatography (silica gel, 5 to 100% ethyl acetate/hexanes) to afford [(S)-1-[1-(2-hydroxy-2-methyl-propyl)-1H-pyrazol-3-ylcarbamoyl]-2-(tetrahydro-pyran-2-yl)-ethyl]-carbamic acid t-butyl ester (600 mg, 57%) as a white solid: LR-ES-MS m/z calculated for C20H34N4O5 [M]+ 410, observed [M+H]+ 411.

Provenance & Evidence