Triethylamine → 2,2-Dimethyl-N-(3-methylpyridin-2-yl)propanamide

Temperature

0 °C

2-Amino-3-methylpyridine (108 g) and triethylamine (180 ml) were dissolved in tetrahydrofuran (500 ml) and the solution cooled to 0° C. in an acetone/ice bath. A solution of pivaloyl chloride (135.4 ml) in tetrahydrofuran (250 ml) was added over 70 minutes at such a rate that the temperature remained between 0° C. and 5° C. The mixture was aged at 0° C. for 15 minutes, allowed to warm to room temperature and aged for 3 hours. The reaction mixture was quenched into water (1 liter), the phases separated and the aqueous phase extracted with ethyl acetate (2×200 ml). The organic phases were combined, washed with saturated sodium bicarbonate solution (2×200 ml), brine (200 ml) and dried (sodium sulphate). The solvent was removed under reduced pressure and the solid residue flushed with hexane (100 ml). The solid was dissolved in hot hexane, filtered and allowed to crystallise. The title compound was collected by filtration, washed with hexane (200 ml) and dried (147.4 g, 76.8% yield; mp 90°-92° C.).

1. customremained between 0° C. and 5° C
2. temperatureto warm to room temperature and aged for 3 hours
3. customThe reaction mixture was quenched into water (1 liter)
4. customthe phases separated
5. extractionthe aqueous phase extracted with ethyl acetate (2×200 ml)
6. washwashed with saturated sodium bicarbonate solution (2×200 ml), brine (200 ml)
7. dry with materialdried (sodium sulphate)
8. customThe solvent was removed under reduced pressure
9. customthe solid residue flushed with hexane (100 ml)
10. dissolutionThe solid was dissolved in hot hexane
11. filtrationfiltered
12. customto crystallise
13. filtrationThe title compound was collected by filtration
14. washwashed with hexane (200 ml)
15. customdried (147.4 g, 76.8% yield; mp 90°-92° C.)

ORD record

ord-8ffb6476017a4c4b99ad0a41569c0174

Source dataset

uspto-grants-1997_10

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US05681959