Hydrochloric Acid → 4-Butylpiperidine

In a 500 mL flask fitted with a stirrer was added a slurry of 2 (13.2 g, 58 mmol) and 10% palladium on charcoal (1.2 g) in ethanol (70 mL), followed by addition of concentrated hydrochloric acid (1.5 mL). The reaction flask was evacuated and hydrogen was added via a reaction flask. A total of 2.5 dm3 of hydrogen was consumed. The reaction mixture was filtered and evaporated and the residue was dissolved in H2O (40 mL) and NaOH (20 mL, 2 M) followed by extraction with ethyl acetate (3×100 mL). The combined organic phases were washed with brine (30 mL) and evaporated to dryness to produce 7.1 g of crude 3. The crude product was subjected to CC [eluent:heptane:EtOAc (4:1)] to give pure 3 (2.7 g, 33%). 1H NMR (CDCl3) δ0.85 (t, 3H), 1.0-1.38 (m, 9H), 1.65 (dd, 2H), 2.38 (s, 1H), 2.55 (dt, 2H), 3.04 (dt, 2H).

1. customIn a 500 mL flask fitted with a stirrer
2. customThe reaction flask was evacuated
3. additionhydrogen was added via a reaction flask
4. customA total of 2.5 dm3 of hydrogen was consumed
5. filtrationThe reaction mixture was filtered
6. customevaporated
7. dissolutionthe residue was dissolved in H2O (40 mL)
8. extractionNaOH (20 mL, 2 M) followed by extraction with ethyl acetate (3×100 mL)
9. washThe combined organic phases were washed with brine (30 mL)
10. customevaporated to dryness
11. customto produce 7.1 g of crude 3

ORD record

ord-7f0a9a9b88ce4875a01a46af6247439e

Source dataset

uspto-grants-2009_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07485651B2