Reaction #45868

Reaction equation

tri-n-butyltin hydride

2,2′-azobisisobutyronitrile

tri-n-butyltin hydride

2-Cyclopropyl-7-[(1R*,3S*,4S*)-3-hydroxy-4-iodocyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

→

compound

Yield 60.0%

2-Cyclopropyl-7-[(1S*,3R*)-3-hydroxycyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile

Yield 60.0%

Solvents

toluene

Conditions

Workup

1. 1
   TemperatureThe solution was heated
2. 2
   Temperatureunder reflux under nitrogen atmosphere for 3 hours
3. 3
   OtherMonitoring the reaction by TLC
4. 4
   TemperatureAfter further heated
5. 5
   Temperatureunder reflux for 1 hour
6. 6
   Temperaturethis was cooled to room temperature
7. 7
   OtherThe solvent was evaporated away under reduced pressure
8. 8
   Otherseparately synthesized
9. 9
   Otherpurified by middle-pressure liquid chromatography (eluent, n-hexane

Procedure

2-Cyclopropyl-7-[(1R*,3S*,4S*)-3-hydroxy-4-iodocyclopentyl]-5-methyl-6-phenyl-1,3-benzoxazole-4-carbonitrile (I-301) (240 mg, 0.50 mol) was dissolved in toluene (4.8 ml), then at room temperature, 2,2′-azobisisobutyronitrile (8 mg, 0.05 mmol) and tri-n-butyltin hydride (180 μl, 0.64 mmol) were added. The solution was heated under reflux under nitrogen atmosphere for 3 hours. Monitoring the reaction by TLC showed the remaining starting material, and the solution was cooled to room temperature and tri-n-butyltin hydride (89 μl, 0.32 mmol) was again added. After further heated under reflux for 1 hour, this was cooled to room temperature. The solvent was evaporated away under reduced pressure, and the resulting residue was combined with the entitled compound (I-302) separately synthesized according to a different method, and purified by middle-pressure liquid chromatography (eluent, n-hexane:ethyl acetate=1:1, v/v) to obtain the entitled compound (113 mg, 60%) as a colorless gel.

Source