Ethyl piperidine-2-carboxylate → HCID 21255125, compound

Participants

Reaction Steps

150.8 g of 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride and 60.3 g of 1-hydroxybenzotriazole hydrate are added to a suspension of 82.4 g of ethyl piperidine-2-carboxylate in 500 cm3 of dichloromethane. The solution remains milky and 45 g of 2-methylnicotinic acid are added. The solution becomes clear and 161 cm3 of triethylamine are added. The mixture is kept stirred at ambient temperature overnight. The mixture is hydrolysed with 2×1 liter of water. The organic phase is then dried over magnesium sulphate and evaporated at reduced pressure (2.7 kPa). The oil obtained is chromatographed on a column of 8 cm diameter containing 900 g of silica (0.04-0.02). Elution is carried out with ethyl acetate, 70-cm3 fractions being collected. The homogeneous fractions are combined and concentrated at reduced pressure (2.7 kPa). 81.86 g of ethyl N-(2-methylnicotinoyl)piperidine-2-carboxylate are thus obtained in the form of a colourless oil (Rf=0.21; thin layer chromatography on silica gel; ethyl acetate eluent).

Provenance & Evidence