Reacción #1960495

Ecuación de reacción

7,8-difluoro-2-pentylchroman-6-ol

1-hexyn-3-ol

triphenylphosphine

DIAD

→

6-(1-ethynylbutoxy)-7,8-difluoro-2-pentylchroman

Disolventes

water

THF

Condiciones de reacción

Tratamiento posterior

1. 1
   workup.ADDITIONare added over the course of 20 min with ice-
2. 2
   Temperaturacooling
3. 3
   Extracciónthe mixture is extracted a number of times with MTBE
4. 4
   LavadoThe combined organic phases are washed with water and saturated sodium chloride soln
5. 5
   Otro, and the solution is dried
6. 6
   Otroafter removal of the solvents
7. 7
   Otrois purified by column chromatography (SiO2, n-heptane:MTBE=2:1)

Procedimiento

10.0 g (39.0 mmol) of 7,8-difluoro-2-pentylchroman-6-ol are initially introduced in 140 ml of THF together with 4.0 g (41.0 mmol) of 1-hexyn-3-ol and 11.3 g (42.9 mmol) of triphenylphosphine, and 9.1 ml (46.8 mmol) of DIAD are added over the course of 20 min with ice-cooling. After 18 h at RT, water is added, and the mixture is extracted a number of times with MTBE. The combined organic phases are washed with water and saturated sodium chloride soln., and the solution is dried using sodium sulfate. The residue remaining after removal of the solvents is purified by column chromatography (SiO2, n-heptane:MTBE=2:1), giving 6-(1-ethynylbutoxy)-7,8-difluoro-2-pentylchroman as a yellow oil.

Fuente