反应详情

温度

-34 °C

A 3-L, 3-neck flask was charged with LiHMDS (1.0 M in THF, 750mL, 0.75 mol) and purged with nitrogen. The flask was cooled to −34° C. An addition funnel was then charged with EtOAc (74 mL, 0.7576 mol) and this reagent was slowly added to the reaction vessel. After complete EtOAc addition another addition funnel was charged with a 2-[4-(3-cyclopentyl-3-oxopropyl)-2-fluorophenyl]-2-methylpropanenitrile solution (crude MTBE soln from prior reaction, theor. 135.49 g, 0.4715 mol) and rinsed over with THF (anhydrous, 20 mL). The ketone solution was added to the reaction flask. Five minutes after complete addition a reaction aliquot was removed and analyzed by HPLC, showing 1% 2-[4-(3-cyclopentyl-3-oxopropyl)-2-fluorophenyl]-2-methylpropanenitrile. Ten minutes after complete ketone addition, the bath was switched to 0° C. Once the internal temperature had warmed to −10° C., 1M NaOH (860 mL) was slowly added. After complete NaOH soln addition, the reaction was heated to 50° C. After 21 hours an aliquot was removed from the top layer and analyzed by HPLC, showing no detectable ethyl 5-[4-(1-cyano-1-methylethyl)-3-fluorophenyl]-3-cyclopentyl-3-hydroxypentanoate. The reaction solution was cooled below 30° C. and added to a separatory funnel with MTBE (1265 mL). The phases were mixed well and separated. An aliquot of the aqueous phase was analyzed by HPLC, verifying no significant product, and this layer was discarded. Water (1265 mL) was added and the phases mixed well and separated. An aliquot of the organic phase was analyzed by HPLC, verifying very little product in this layer, and the organic phase was discarded. The aqueous phase was added to a flask. Concentrated aq. HCl (˜49 mL) was added to the aqueous phase until the pH=2. The mixture was added back to a separatory funnel with IPE (1265 mL) and mixed well. An aliquot of the aqueous phase verified no significant product, and this layer was discarded. The organic layer was dried (MgSO4, 25 g), filtered, and the cake rinsed with IPE (200 mL). The solution was analyzed by K—F titration, showing 0.93% water content. This solution was charged to a 3-L, 3-neck flask. While stirring well, dicyclohexylamine (188 mL, 0.9446 mol) was added. The amine addition caused an exotherm to 28° C. After 10 min, significant solids were observed. The solution was stirred at rt for 2.5 h. The solution was cooled in a 0° C. bath until the internal temp remains below 5° C. for 2 h. The slurry is filtered, and the solids rinsed with cold (5° C.) IPE (250 mL). The solids were dried to provide 189.68 g of 5-[4-(1-cyano -1-methylethyl)-3-fluorophenyl]-3-cyclopentyl-3-hydroxypentanoic acid dicyclohexylamine salt as a white powder. The solids had a 98.4% purity by HPLC and were clean by 1H NMR.

1. custompurged with nitrogen
2. additionthis reagent was slowly added to the reaction vessel
3. customreaction, theor
4. wash135.49 g, 0.4715 mol) and rinsed over with THF (anhydrous, 20 mL)
5. additionThe ketone solution was added to the reaction flask
6. additionFive minutes after complete addition a reaction aliquot
7. customwas removed
8. additionTen minutes after complete ketone addition
9. customwas switched to 0° C
10. temperatureOnce the internal temperature had warmed to −10° C.
11. addition1M NaOH (860 mL) was slowly added
12. additionAfter complete NaOH soln addition
13. temperaturethe reaction was heated to 50° C
14. customAfter 21 hours an aliquot was removed from the top layer
15. temperatureThe reaction solution was cooled below 30° C.
16. additionadded to a separatory funnel with MTBE (1265 mL)
17. additionThe phases were mixed well
18. customseparated
19. additionWater (1265 mL) was added
20. additionthe phases mixed well
21. customseparated
22. additionThe aqueous phase was added to a flask
23. additionConcentrated aq. HCl (˜49 mL) was added to the aqueous phase until the pH=2
24. additionThe mixture was added back to a separatory funnel with IPE (1265 mL)
25. additionmixed well
26. dry with materialThe organic layer was dried (MgSO4, 25 g)
27. filtrationfiltered
28. washthe cake rinsed with IPE (200 mL)
29. additionThis solution was charged to a 3-L, 3-neck flask
30. customto 28° C
31. stirringThe solution was stirred at rt for 2.5 h
32. temperatureThe solution was cooled in a 0° C. bath until the internal temp
33. waitremains below 5° C. for 2 h
34. filtrationThe slurry is filtered
35. washthe solids rinsed with cold (5° C.) IPE (250 mL)
36. customThe solids were dried