tert-Butyl piperazine-1-carboxylate → 1,1-Dimethylethyl 4-(5-chloro-8-quinolinyl)-1-piperazinecarboxylate

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-chloroquinolin-8-yl trifluoromethanesulfonate (1.8 g, 5.78 mmol), Cesium carbonate (2.63 g, 8.09 mmol), rac-2,2'-Bis(diphenylphosphino)-1,1'-binaphthyl (0.180 g, 0.29 mmol), tert- Butyl 1-piperazinecarboxylate (1.291 g, 6.93 mmol) and Palladium(II) acetate (0.065 g, 0.29 mmol) in THF (30 mL) under a nitrogen atmosphere was stirred at 75 °C for 6h. The solution was cooled to rt and diluted with ether. The mixtture was filtered through celite and the solvent was evaporated under reduced pressure. The residue was purified by flash chromatography on silica gel, eluting with a gradient of 25-50% EtOAc in heptane, to afford tert-butyl 4-(5-chloroquinolin-8-yl)piperazine-1-carboxylate (0.489 g, 24.34 %) as an oil. 1H NMR (400 MHz, CHLOROFORM- _d_ ) d ppm 1.51 (s, 9 H), 3.28 - 3.37 (m, 4 H), 3.72 - 3.82 (m, 4 H), 7.06 (d, _J_ =7.81 Hz, 1 H), 7.48 - 7.57 (m, 2 H), 8.57 (dd, _J_ =8.59, 1.95 Hz, 1 H), 8.94 (dd, _J_ =4.10, 1.76 Hz, 1 H); MS m/z 348.31 [M+H]+ (ESI).

Provenance & Evidence