反应详情

To 2-aminomethyl-3-chloropyrazine hydrochloride (content 76%, 69.4 mmol, 16.43 g), cis-4-hydroxycyclohexanecarboxylic acid (69.4 mmol, 10 g), 1-(3-dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (104 mmol, 19.95 g), 4-dimethylaminopyridine (6.94 mmol, 0.847 g) in dichloromethane (200 ml) was added N,N-diisopropylethylamine (173 mmol, 30.3 ml, 22.41 g) until pH became eight and the reaction mixture was stirred at room temperature for 18 hours. Then it was concentrated in vacuo, ethyl acetate and water were added and the organic layer separated. The water layer was extracted with ethyl acetate twice. The combined organic layers were washed with brine, dried (MgSO4) and concentrated in vacuo. The residue was purified by column chromatography (silica gel; dichloromethane with gradient of 0% to 7% methanol). All fractions that contained product were combined and concentrated in vacuo. The residue was dissolved in dichloromethane (400 ml) and washed with 2 M sodium hydroxide (aq) (three times 100 ml), washed with brine, dried (MgSO4) and concentrated in vacuo to give (cis)-N-((3-chloropyrazin-2-yl)methyl)-4-hydroxycyclohexanecarboxamide (15.47 g)

1. concentrationThen it was concentrated in vacuo, ethyl acetate and water
2. additionwere added
3. customthe organic layer separated
4. extractionThe water layer was extracted with ethyl acetate twice
5. washThe combined organic layers were washed with brine
6. dry with materialdried (MgSO4)
7. concentrationconcentrated in vacuo
8. customThe residue was purified by column chromatography (silica gel; dichloromethane with gradient of 0% to 7% methanol)
9. concentrationconcentrated in vacuo
10. dissolutionThe residue was dissolved in dichloromethane (400 ml)
11. washwashed with 2 M sodium hydroxide (aq) (three times 100 ml)
12. washwashed with brine
13. dry with materialdried (MgSO4)
14. concentrationconcentrated in vacuo