Reacción #986433

Ecuación de reacción

4-[2-(1-hydroxy-1-methylethyl)phenyl]-1-methylpiperidin-4-ol

4-[2-(1-Hydroxy-1-methylethyl)phenyl]-1-methylpiperidin-4-ol

boron trifluoride diethyl etherate

→

title compound

Rendimiento 56.0%

1′,3,3-Trimethyl-3H-spiro[2-benzofuran-1,4′-piperidine]

Rendimiento 56.0%

Disolventes

benzene

Condiciones de reacción

Tratamiento posterior

1. 1
   OtroThe reaction mixture was quenched by the addition of water (200 mL) and 2 N sodium hydroxide aqueous solution (200 mL)
2. 2
   Otrothe benzene layer was separated
3. 3
   ExtracciónThe aqueous layer was extracted with diethyl ether
4. 4
   Lavadocombined organic layer washed with brine
5. 5
   Secadodried over sodium sulfate
6. 6
   Otroevaporated
7. 7
   OtroThe residue was purified by column chromatography on an amine coated silica gel (100 g)
8. 8
   Lavadoeluting with dichloromethane

Procedimiento

To a stirred solution of 4-[2-(1-hydroxy-1-methylethyl)phenyl]-1-methylpiperidin-4-ol (step 2, 4.62 g, 18.5 mmol) in benzene (200 mL) was added dropwise boron trifluoride diethyl etherate (11.0 mL, 86.8 mmol) at room temperature and the mixture was stirred for 40 h at the same temperature. The reaction mixture was quenched by the addition of water (200 mL) and 2 N sodium hydroxide aqueous solution (200 mL), and the benzene layer was separated. The aqueous layer was extracted with diethyl ether, and then combined organic layer washed with brine, dried over sodium sulfate, and evaporated. The residue was purified by column chromatography on an amine coated silica gel (100 g) eluting with dichloromethane to afford 2.39 g (56%) of the title compound as a colorless solid:

Fuente