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

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

A mixture of 3,5-dibromopyridine (3.01 mL, 12.66 mmol), morpholine (1.00 g, 11.48 mmol), TRIS(DIBENZYLIDENEACETONE)DIPALLADIUM (0.210 g, 0.23 mmol), sodium 2-methylpropan-2-olate (1.655 g, 17.22 mmol) and 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl (0.429 g, 0.69 mmol) in degassed toluene (35 mL) was stirred for 16 hours at 110 °C in a sealed vessel under inert atmosphere. Extraction with sat. aq. Na2CO3 solution and AE, then back extraction 2x NaCl sat using DCM. The organics were dried over MgSO4 and evaporated _in vacuo_. The residue (see structure below, LC MS FLA-04227-45-02: 3,5 dimorpholino pyridine) was washed off with diethylether, then AE. The liquors were vaporated _in vacuo_. The residue was purified by chromatography (11 cm SiO2, diameter: 5 cm) eluent: AE/hex 25/75to 45/55 to provide 4-(5-bromopyridin-3-yl)morpholine (1.400 g, 50.2 %) as a yellow solid. 1H NMR, LC MS: FLA-04227-45-03. OK \---------------------------------------------------------

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