Reaction #1960501

Reaction equation

5,6-difluoro-3-propyl-8-(4-propylcyclohexyl)-7,8,9,10-tetrahydro-3H-benzo[f]chromene

→

5,6-difluoro-3-propyl-8-(4-propylcyclohexyl)-2,3,7,8,9,10-hexahydro-1H-benzo[f]chromene

Solvents

THF

Conditions

Workup

1. 1
   FiltrationThe reaction solution is filtered
2. 2
   Otherthe filtrate is evaporated to dryness
3. 3
   OtherThe residue is purified by column chromatography (SiO2, n-heptane:toluene=9:1)
4. 4
   OtherThe further purification
5. 5
   Otheris carried out by recrystallisation from ethanol
6. 6
   Othergiving

Procedure

5.0 g (about 11.4 mmol) of 5,6-difluoro-3-propyl-8-(4-propylcyclohexyl)-7,8,9,10-tetrahydro-3H-benzo[f]chromene are hydrogenated at atmospheric pressure in THF and in the presence of Pd/C (5% of Pd). The reaction solution is filtered, and the filtrate is evaporated to dryness. The residue is purified by column chromatography (SiO2, n-heptane:toluene=9:1). The further purification is carried out by recrystallisation from ethanol, giving a 1:1 mixture of isomeric 5,6-difluoro-3-propyl-8-(4-propylcyclohexyl)-2,3,7,8,9,10-hexahydro-1H-benzo[f]chromenes (m.p. 89° C.). This can be resolved, for example, by preparative HPLC.

Source