4-Pyridineacetic acid hydrochloride → 4-Piperidineacetic acid

Pyridin-4-yl-acetic acid hydrochloride (20.0 g, 115 mmol) was added to water/25% ammonia (125 mL:10 mL). The mixture was degassed and flushed with nitrogen before addition of rhodium on activated alumina (0.45 g). The mixture was again degassed, then stirred in a hydrogen atmosphere at 50 bar for 16 h. Filtration of the reaction mixture through filter paper afforded the bulk of the catalyst which was recycled after washing with methanol. The filtrate was then filtered through Celite and concentrated to afford a white solid (19.7 g, 96% yield).

1. customThe mixture was degassed
2. customflushed with nitrogen before addition of rhodium on activated alumina (0.45 g)
3. customThe mixture was again degassed
4. filtrationFiltration of the reaction mixture
5. filtrationthrough filter paper
6. customafforded the bulk of the catalyst which
7. washafter washing with methanol
8. filtrationThe filtrate was then filtered through Celite
9. concentrationconcentrated

ORD record

ord-daaa1dd8532d4b07b2dcd390bf1035bb

Source dataset

uspto-grants-2008_04

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US07354895B1