2,5-Dibromopyridine → 3-(5-Bromo-pyridine-2-carbonyl)-pyrrolidine-1-carboxylic acid tert-butyl ester

Beteiligte Stoffe

Reaktionsbedingungen

Reaktionsschritte

Add dropwise n-BuLi (3.2 mL, 5.1 mmol) to an suspension of 2,5-dibromopyridine (1.0 g, 4.2 mmol) in dry toluene (50 mL) at −80° C. under nitrogen. Allow the mixture to stir at −80° C. for 2 h. Slowly add a solution of 3-(methoxy-methyl-carbamoyl)-pyrrolidine-1-carboxylic acid tert-butyl ester (1.4 g, 5.5 mmol) in dry toluene (10 mL). Allow the reaction mixture to stir for 1 h at −78° C., then warm to −10° C. Quench the mixture with saturated NH4Cl (1 mL) and warm to RT. Separate the organic layer and concentrate. Purify the crude material by flash chromatography, eluting with 10-20% ethylacetate/hexane to give 0.61 g (43%) of the title compound. LC-MS/ES m/z (79Br) 299 [M-tert-Bu+H]+.

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