反应详情

Sodium triacetoxyborohydride (1.5 g) is added to a mixture of 1-benzylpiperazine (714 μl), N,N-dimethyl-2-(4-oxocyclohexyl)acetamide (820 mg) and acetic acid (680 μl) in THF (50 ml). The mixture is stirred over night. An aqueous solution of potassium carbonate (20%) is added and the mixture stirred for 30 min. The organic layer is separated and the aqueous layer is extracted with EtOAc. The combined organic layers are washed with satd. aqueous NH4Cl (2×), dried (Na2SO4) and filtered, and the solvent is removed under reduced pressure. The crude product is purified using reverse phase HPLC (Varian C18 Microsorb) eluting with a gradient of 10-100% acetonitrile in water containing 0.2% trifluoroacetic acid to give 2-(4-(4-benzylpiperazin-1-yl)cyclohexyl)-N,N-dimethylacetamide (800 mg). m/z(+) 344 (M+H+). The 2-(pyrrolidin-1-yl)ethanamine and the tert-butyl 4-oxopiperidine-1-carboxylate used to synthesize 34 were purchased from Aldrich. The tert-butyl 3-oxocyclohexylcarbamate used to synthesize 50 was purchased from AB Chem. The 1-benzyl-1,4-diazepane used to synthesize 52 was purchased from Lancaster.

1. stirringthe mixture stirred for 30 min
2. customThe organic layer is separated
3. extractionthe aqueous layer is extracted with EtOAc
4. washThe combined organic layers are washed with satd
5. dry with materialaqueous NH4Cl (2×), dried (Na2SO4)
6. filtrationfiltered
7. customthe solvent is removed under reduced pressure
8. customThe crude product is purified
9. washeluting with a gradient of 10-100% acetonitrile in water containing 0.2% trifluoroacetic acid