Trifluoroacetic acid → 1-(Piperidin-4-yl)-1,2,3,6-tetrahydropyridine

tert-Butyl 4-(5,6-dihydropyridin-1 (2H)-yl)piperidine-1-carboxylate (800 mg, 3 mmol) was dissolved in dichloromethane (54 ml). To this was added trifluoroacetic acid (7.9 ml) and triethyl silane (1.2 ml). The mixture was stirred at room temperature for 3 h. Solvent was removed from the mixture en vacuo. The residue was dissolved in saturated sodium bicarbonate (50 ml) and stirred for 30 min. Sodium hydroxide (50 ml, 50% in water) was added to the solution which was then extracted with dichloromethane (3×100 ml). The organic extract was dried over sodium sulfate and the solvent evaporated to give 370 mg (74%) as a colorless oil. 1H-NMR (CDCl3, 400 MHz) δ 5.74-5.70 (m, 1H), 5.68-5.64 (m, 1H), 3.14-3.07 (m, 4H), 2.64-2.53 (m, 4H), 2.43-2.37 (m, 1H), 2.15 (m, 2H), 1.85-1.82 (m, 2H), 1.73 (s, 1H), 1.47-1.38 (m, 2H).

1. customSolvent was removed from the mixture en vacuo
2. dissolutionThe residue was dissolved in saturated sodium bicarbonate (50 ml)
3. stirringstirred for 30 min
4. additionSodium hydroxide (50 ml, 50% in water) was added to the solution which
5. extractionwas then extracted with dichloromethane (3×100 ml)
6. extractionThe organic extract
7. dry with materialwas dried over sodium sulfate
8. customthe solvent evaporated
9. customto give 370 mg (74%) as a colorless oil

ORD record

ord-a34d6e3f977049f79c03ed99a0291708

Source dataset

uspto-grants-2010_08

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07772244B2