Carbon Dioxide → 2-(2-Pyridyl)-2-propylamine

Temperature

-76 °C

Add THF (240 mL) to anhydrous cerium (III) chloride (35 g, 144 mmol) and stir the slurry under nitrogen for 30 minutes. Cool the mixture to −76° C. in a dry-ice acetone bath. Add a 1.6 M solution of methyl lithium in Et2O (90 mL, 144 mmol) dropwise maintaining the internal reaction temperature below −60° C. Stir for 30 minutes after the addition is complete, cool the reaction to −76° C., then add 2-cyanopyridine (5 g, 48 mmol) as a solution in THF (20 mL) controlling the addition to keep the reaction below −60° C. Stir the mixture in the dry-ice bath for 15 minutes, then remove the bath and allow the reaction to warm to 15° C. Cool the reaction in the dry-ice bath then add ammonium hydroxide (90 mL) with stirring. Allow the reaction to warm to room temperature with stirring overnight. Decant the solution from the mixture and wash the solids well with THF. Combine the filtrate and washes, then evaporate to give 1-methyl-1-pyridin-2-yl-ethylamine in quantitative mass balance. 1H NMR (400 MHz, CDCl3): δ 8.52 (d, J=4.0 Hz, 1H), 7.60 (td, J=7.7, 1.6 Hz, 1H), 7.42 (d, J=7.9 Hz, 1H), 7.15-7.08 (m, 1H), 1.47 (s, 6H).

1. temperaturedropwise maintaining the internal reaction temperature below −60° C
2. stirringStir for 30 minutes
3. additionafter the addition
4. temperaturecool
5. customthe reaction to −76° C.
6. additionthe addition
7. customthe reaction below −60° C
8. customremove the bath
9. customthe reaction
10. temperatureto warm to 15° C
11. temperatureCool
12. customthe reaction
13. temperatureto warm to room temperature
14. stirringwith stirring overnight
15. customDecant the solution from the mixture
16. washwash the solids well with THF
17. customevaporate

ORD record

ord-1eeb64f648904d86b4a089130b478dc6

Source dataset

uspto-grants-2013_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08426448B2