4-Methylmorpholine → Benzyl (2R)-2-Benzyl-3-(4-trifluoroethylpiperazin-1-ylcarbonyl)propionate

Participants

Reaction Conditions

Reaction Steps

The resultant acid from Example 23 (0.500 g, 1.68 mmol) in CH2Cl2 (7 ml) at -10° C. was treated with N-methylmorpholine (0.20 ml, 1.82 mmol) and then isobutyl chloroformate (0.22 ml, 1.68 mmol). After 5 min 1-trifluoroethylpiperazine (0.30 g, 1.78 mmol) was added and the mixture was stirred at -10° C. for 15 min and then at room temperature for 2 h. The solvent was evaporated and the residue was taken up in ethyl acetate which was washed with saturated NaHCO3 solution, water and brine, and then dried over Na2SO4 and evaporated. Chromatography of the residue on silica gel with 20-33% ethyl acetate in hexane provided 0.61 g (81%) of an oil. 1H NMR (CDCl3) δ7.10-7.40 (m,10H), 5.15 (d,1H), 5.05 (d,1H), 3.25-3.70 (m,5H), 3.04 (dd,1H), 2.97 (q,2H), 2.81 (dd,1H), 2.72 (dd,1H), 2.60 (m,4H), 2.32 (dd,1H).

Provenance & Evidence