Hexane → 5-Ethenyl-2-(trifluoromethyl)pyridine

A suspension of methyltriphenylphosphonium bromide (24.4 g, 68.4 mmol) in THF (150 mL) at −78° C. under an atmosphere of nitrogen was added 2.5 M of n-butyllithium in hexane (27 mL, 67.5 mmol) during a period of 12 mins. The reaction was warmed to room temperature to give a deep red ylide solution. To the ylide solution, cooled in ice, was introduced a solution of 6-(trifluoromethyl)nicotinaldehyde (10 g, 57 mmol) in THF (50 mL). The reaction mixture was warmed to room temperature and stirred for 3 hours. The result suspension was heated to 60° C. over 30 minutes and then stirred at 60° C. for 1 hour. After cooling, the mixture was diluted with water (400 mL), and extracted with EtOAc. The organic layer was washed with brine, dried (MgSO4), and concentrated. The residue was purified by silica gel column (0-10% EtOAc/hexane) to afford title compound.

1. customto give a deep red ylide solution
2. temperatureTo the ylide solution, cooled in ice
3. temperatureThe reaction mixture was warmed to room temperature
4. temperatureThe result suspension was heated to 60° C. over 30 minutes
5. stirringstirred at 60° C. for 1 hour
6. temperatureAfter cooling
7. extractionextracted with EtOAc
8. washThe organic layer was washed with brine
9. dry with materialdried (MgSO4)
10. concentrationconcentrated
11. customThe residue was purified by silica gel column (0-10% EtOAc/hexane)

ORD record

ord-391afc12535044899888b05c4c91f9e5

Source dataset

uspto-grants-2015_02

DOI

10.6084/m9.figshare.5104873.v1

Patent number

US08946439B2