Reaction #2507833

Reaction equation

6,8-Difluoro-3-[2-(6-fluoro-3-pentylchroman-7-yl)vinyl]-2H-chromene

→

6,8-Difluoro-3-[2-(6-fluoro-3-pentylchroman-7-yl)ethyl]-2H-chromene

Solvents

THF

Conditions

Workup

1. 1
   FiltrationThe catalyst is filtered off
2. 2
   Otherthe solution is evaporated
3. 3
   Filtrationthe residue is filtered through silica gel with toluene/heptane (3:2)
4. 4
   Otherthe crude product is recrystallised from n-heptane at −25° C.
5. 5
   Othergiving colourless crystals of m.p. 84° C.

Procedure

6,8-Difluoro-3-[2-(6-fluoro-3-pentylchroman-7-yl)vinyl]-2H-chromene is dissolved in THF and hydrogenated to completion on a palladium/active carbon catalyst. The catalyst is filtered off, the solution is evaporated, the residue is filtered through silica gel with toluene/heptane (3:2), and the crude product is recrystallised from n-heptane at −25° C., giving colourless crystals of m.p. 84° C.

Source