Acetic Acid → (+/-)-(5-Bromo-pyridin-2-yl)-(1-methyl-pyrrolidin-3-yl)-methanone

Participants

Reaction Steps

To a solution of (5-bromo-pyridin-2-yl)-pyrrolidin-3-yl-methanone (0.35 g, 1.35 mmol) in methanol (68 mL), add acetic acid (0.15 mL, 2.7 mmol), and formaldehyde (0.33 g, 4.1 mmol, 37% aqueous solution). After 15 min, add sodium triacetoxyborohydride (0.86 g, 4.1 mmol) and allow the mixture to stir at RT for 1 h. Concentrate the reaction mixture, dissolve in CH2Cl2, and wash with saturated NaHCO3. Back-extract the aqueous with CH2Cl2. Wash the combined organic layer with water, dry over Na2SO4, filter, and concentrate. Purify the crude material by flash chromatography, eluting with 5-10% MeOH (2N NH3)/CH2Cl2 to give 0.17 g (47%) of the title compound. LC-MS/ES m/z (79Br) 270 [M+H]+.

Provenance & Evidence