Cesium carbonate → 4',6'-Dimethyl-2,3,5,6-tetrahydro-[1,2']bipyridinyl-4-one

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Caesium carbonate (48.05 g, 141.3 mmol) was added to a solution of piperidin-4-one hydrochloride (7.6 g, 56.5 mmol) in toluene (20 mL) and stirred for 15-20 min under argon. A solution of 2-chloro-4,6-dimethyl-pyridine (4.0 g, 28.3 mmol) in tetrahydrofuran (10 mL) was added dropwise followed successively by palladium acetate (63 mg, 0.28 mmol) and (±)-(1,1′-binaphthalene-2,2′-diyl)bis(diphenylphosphine) (BINAP) (0.174 g, 0.28 mmol). The reaction mixture was heated at reflux overnight then cooled to 0° C., diluted with water and extracted with ethyl acetate. The organic phase was washed with brine, dried over anhydrous sodium sulfate and concentrated in vacuo to give a residue which was purified by column chromatography over silica gel (60-120 mesh) using 10% ethyl acetate in hexane as eluent to afford 4′,6′-dimethyl-2,3,5,6-tetrahydro-[1,2′]bipyridinyl-4-one (450 mg, 8%) as a yellow solid.

Herkunft & Nachweise