Cesium carbonate → tert-butyl 4-{3-[(3R)-3-({1-[4-(2-fluoroethoxy)phenyl]-3-methoxy-3-oxopropyl}carbamoyl)piperidin-1-yl]-3-oxopropyl}piperidine-1-carboxylate

Participants

Reaction Steps

150 mg (0.28 mmol) 4-(3-{(R)-3-[1-(4-hydroxy-phenyl)-2-methoxycarbonyl-ethylcarbamoyl]-piperidin-1-yl}-3-oxo-propyl)-piperidine-1-carboxylic acid tert-butyl ester were dissolved in 3 ml tetrahydrofurane. 179 mg (0.55 mmol) cesium carbonate and 91 mg (0.52 mmol) 1-iodo-2-fluoroethane were added. The mixture was stirred at room temperature for 60 hours and filtrated. The filtrate was concentrated. Chromatography over 10 g silica gel (dichloromethane ethanol 100/0-90/10) gave 90 mg (50%) tert-butyl 4-{3-[(3R)-3-({1-[4-(2-fluoroethoxy)phenyl]-3-methoxy-3-oxopropyl}carbamoyl)piperidin-1-yl]-3-oxopropyl}piperidine-1-carboxylate and 40 mg starting material.

Provenance & Evidence