N,N-Dimethylpiperidin-4-amine → HCID 59909810, compound

A solution of ethyl 5-{(1R)-1-[2-(tert-butoxy)-2-oxoethyl]-4-cyclohexylbutyl}-1,2,4-oxadiazole-3-carboxylate (Preparation 3) (800 mg, 2.03 mmol) in ethanol (10 ml) was treated with N,N-dimethyl-N-(4-piperidinyl)amine (1.23 g, 9.61 mmol) and the resulting mixture was heated under reflux under a nitrogen atmosphere for 3 hours. The solvent was removed under reduced pressure and the residue was partitioned between ethyl acetate and water. The layers were separated and the aqueous layer was extracted with ethyl acetate. The combined organic layers were washed sequentially with water and brine, dried over anhydrous sodium sulphate, filtered and the solvent was removed under reduced pressure. The residue was purified by column chromatography on silica gel eluting with dichloromethane:methanol (90:10) to give a residue which was further purified by column chromatography on silica gel eluting with dichloromethane:methanol:0.88 ammonia (90:10:0.5) to afford the title compound as a yellow oil (653 mg).