Cesium carbonate → tert-Butyl 3-(2-methoxy-2-oxo-ethyl)-4-(2-methyl-4-quinolyl)piperazine-1-carboxylate

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

4-Chloroquinaldine (263 mg, 1.481 mmol), tert-butyl 3-(2-methoxy-2-oxo-ethyl)piperazine-1-carboxylate (318 mg, 1.231 mmol) and caesium carbonate (885 mg, 2.72 mmol) were mixed with anhydrous toluene (4 ml) in an argon atmosphere. 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (128 mg, 0.221 mmol) and tris(dibenzylideneacetone)dipalladium(0) (67 mg, 0.073 mmol) were added and the resulting mixture was stirred at 110° C. for six hours. Additional 9,9-dimethyl-4,5-bis(diphenylphosphino)xanthene (128 mg, 0.221 mmol) and tris(dibenzylideneacetone)dipalladium(0) (67 mg, 0.073 mmol) were added and the mixture was stirred at 110° C. overnight. After reaching room temperature the mixture was filtered, the filtrate was evaporated to dryness to give a red oil that was purified by column chromatography (silica, gradient from DCM to DCM/methanol 1:20) to yield 136 mg of a yellow foam (0.214 mmol, 17%). MS (ESI) m/z=400.2 [M+1]+.

Herkunft & Nachweise