Dimethyl-(2-pyridin-3-yl-cyclohex-2-enylmethyl)amine hydrochloride → cis-Dimethyl-(2-pyridin-3-yl-cyclohexylmethyl)amine hydrochloride

6.90 g dimethyl-(2-pyridin-3-yl-cyclohex-2-enylmethyl)amine hydrochloride were dissolved in 70 ml methanol and hydrogenated in the presence of 1.04 g palladium-on-active charcoal (10 percent by weight) for five hours under a hydrogen pressure of 2 bar. The mixture was then filtered, the filtrate was concentrated in vacuo, the residue was converted into the base with two molar sodium hydroxide solution and a mixture of equal volumes of ethyl acetate and tetrahydrofuran and the base was extracted with ethyl acetate. After drying and concentration, the residue (4.47 g) was chromatographed on silica gel with a mixture of equal volumes of methanol, ethyl acetate and n-hexane. The main fraction (3.72 g) was dissolved in approx. 40 ml acetone/ethanol (V/V=9:1), and half a molar equivalent of water and one molar equivalent of chlorotrimethylsilane were added. After the mixture had been stirred overnight, it was concentrated to dryness, the residue was treated in an ultrasonic bath with 72 ml THF and 18 ml ethanol for 30 minutes, the suspension was stirred overnight and filtered with suction and the residue was dried. 2.42 g cis-dimethyl-(2-pyridin-3-yl-cyclohexylmethyl)amine hydrochloride with a melting point of 219-222° C. were obtained.

1. filtrationThe mixture was then filtered
2. concentrationthe filtrate was concentrated in vacuo
3. additiona mixture of equal volumes of ethyl acetate and tetrahydrofuran
4. extractionthe base was extracted with ethyl acetate
5. customAfter drying
6. concentrationconcentration
7. customthe residue (4.47 g) was chromatographed on silica gel with a mixture of equal volumes of methanol, ethyl acetate and n-hexane
8. dissolutionThe main fraction (3.72 g) was dissolved in approx. 40 ml acetone/ethanol (V/V=9:1)
9. additionhalf a molar equivalent of water and one molar equivalent of chlorotrimethylsilane were added
10. concentrationit was concentrated to dryness
11. additionthe residue was treated in an ultrasonic bath with 72 ml THF and 18 ml ethanol for 30 minutes
12. stirringthe suspension was stirred overnight
13. filtrationfiltered with suction
14. customthe residue was dried

ORD record

ord-b23fabec6d8f42a88149b368ffe5ffeb

Source dataset

uspto-grants-2008_06

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07384961B2