反应详情

A mixture of 2-phenyl-5-trifluoromethyl-oxazole-4-carboxylic acid (0.67 g, 2.6 mmol), 4-(5-amino-pyridin-2-ylamino)-piperidine-1-carboxylic acid tert-butyl ester (0.76 g, 2.6 mmol), bromo-tris-pyrrolidino-phosphonium hexafluorophosphate (PyBrop, 1.45 g, 3.1 mmol), and diisopropylethylamine (0.9 mL, 5.2 mmol) in anhydrous dichloromethane (15 mL) was stirred at room temperature overnight. The reaction mixture was then concentrated and purified by flash chromatography (Merck silica gel 60, 230-400 mesh, eluted with ethyl acetate and hexane) to give 4-{5-[(2-phenyl-5-trifluoromethyl-oxazole-4-carbonyl)-amino]-pyridin-2-ylamino}-piperidine-1-carboxylic acid tert-butyl ester (0.78 g, 56%) as a white solid. LCMS calcd for C26H28F3N5O4 (m/e) 531, obsd 532 (M+H).

1. concentrationThe reaction mixture was then concentrated
2. custompurified by flash chromatography (Merck silica gel 60, 230-400 mesh, eluted with ethyl acetate and hexane)