tert-Butyl piperazine-1-carboxylate → Tert-butyl 4-(2-methylquinolin-5-yl)piperazine-1-carboxylate

Participants

Reaction Steps

A stirred mixture of Pd(OAc)2 (243 mg), CsCO3 (6.63 g), and 2,2′-bis(diphenylphosphino)-1,1′-binaphthyl (1.01 g) in dry toluene (60 mL) was heated under reflux for 15 min, under argon. After cooling, a solution of tert-butyl piperazine-1-carboxylate (3.03 g, 16.3 mmol) and the 2-methylquinolin-5-yl trifluoromethane-sulfonate prepared in example 5 (3.95 g, 13.6 mmol) in toluene (100 mL) was added, and the resulting mixture was heated under reflux for 8 h. The reaction mixture was cooled to room temperature, concentrated to half of its value, and then quenched with saturated solution of NH4Cl (50 mL). The organic layer was separated, the aqueous layer was extracted with EtOAc, and the combined organic solutions were concentrated in vacuo. The residue was purified by column chromatography using CH2Cl2 as eluent. Yield: 4.29 g (96.6%), brown oil. Rf=0.64 (CH2Cl2-MeOH (19:1).

Provenance & Evidence