Morpholine → 4-(5-Bromopyridin-3-yl)morpholine

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

In a sealable tube, to a mixture of 3,5-dibromo-pyridine (3.3 g, 13.8 mmol) and NaOtBu (0.051 g, 23 mmol) in toluene (70 mL), is added morpholine (1.0 g, 11.5 mmol). The mixture is bubbled with Argon for 5 min, and then BINAP (428.9 mg, 0.69 mmol) and Pd2(dba)3 (210.2 mg, 0.23 mmol) are added. The reaction mixture is bubbled with Argon for another 5 min. Then the cap is sealed and the reaction mixture is heated at 120° C. overnight and then is cooled to room temperature. The reaction mixture is filtered through diatomaceous earth and washed with DCM. The filtrate is partitioned between water and DCM. The aqueous phase is further extracted with DCM (2×). The combined DCM phases are concentrated. The crude is purified by flash chromatography on a silica gel column (EtOAc/heptane 0 to 50% gradient, then 50%) to provide 1.42 g of 4-(5-bromo-3-pyridyl)morpholine.

Herkunft & Nachweise