Acetic Acid → 3-(1-{2-[2-(2-Oxopiperidin-1-yl)phenyl]ethyl}azetidin-3-yl)benzonitrile oxalate

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Reaction Steps

To [2-(2-oxopiperidin-1-yl)phenyl]acetaldehyde a3-1 (108.6 mg, 0.5 mmol, 1 eq) and 3-(azetidin-3-yl)benzonitrile a3-2 (97.33 mg, 0.5 mmole, 1 eq) in methanol (4 ml) are added acetic acid (42.9 μl, 0.75 mmol, 1.5 eq) then NaBH3CN (94.3 mg, 1.5 mmol, 3 eq). The reaction mixture is stirred overnight at room temperature. The crude reaction mixture is then loaded on an ion exchange acidic resin cartridge (2 g) prewashed with methanol. The cartridge is washed twice with approximately 3 column volumes of methanol, then eluted with 3 column volumes of 1M NH3 in methanol. This eluate is evaporated to dryness to give 141 mg of a crude material which is purified by reverse phase chromatography (basic mode; gradient: H2O/acetonitrile/NH4OH from 60/40/0.1 to 30/70/0.1 in 10 minutes). The residue obtained is redissolved in acetone (approximately 3 ml), and after addition of oxalic acid (22.7 mg, 0.25 mmol, 1 eq), a precipitate slowly appeared. This precipitate is filtered, washed with diethylether and dried overnight under vacuum at 40° C. to afford 69.6 mg of 3-(1-{2-[2-(2-oxopiperidin-1-yl)phenyl]ethyl}azetidin-3-yl)benzonitrile oxalate 31.

Provenance & Evidence