反应详情

A turbid solution of 1.245 g (3.58 mmol) phosphonitrilic chloride trimer in 20 ml dichloromethane was cooled to −75° C. To this mixture 1.02 ml (14.32 mmol) DMSO were added, and stirring was continued for 1 h. Then a suspension of 1.28 g (3.58 mmol; 1 eq.; example 37.1) [rac]-2-[2-(4-chloro-phenyl)-4,5,6,7-tetrahydro-2H-indazol-3-yl]-2-cyclohexyl-ethanol in 50 ml dichloromethane was added dropwise over 10 min to the turbid reaction mixture, keeping the temperature below −60° C. The reaction mixture was then stirred 1 h at −75° C. Then the mixture was stirred in an ice-bath, and at 0° C. 2.50 ml (17.91 mmol) triethylamine were added. The solution was stirred 1.5 h at 0° C. and then at ambient temperature overnight. The reaction mixture was poured onto 120 ml water, extracted 3 times with dichloromethane. The organic layers were washed with water and brine, dried over MgSO4, filtered and evaporated to give the crude product which was purified on a 20 g silica gel column using a gradient from heptane (A) and ethyl acetate (B) to give the title aldehyde.

1. additionwas added dropwise over 10 min to the turbid reaction mixture
2. customthe temperature below −60° C
3. stirringThe reaction mixture was then stirred 1 h at −75° C
4. stirringThen the mixture was stirred in an ice-bath
5. customat 0° C
6. stirringThe solution was stirred 1.5 h at 0° C.
7. customat ambient temperature
8. customovernight
9. extractionextracted 3 times with dichloromethane
10. washThe organic layers were washed with water and brine
11. dry with materialdried over MgSO4
12. filtrationfiltered
13. customevaporated
14. customto give the crude product which
15. customwas purified on a 20 g silica gel column