반응 #340390

반응 방정식

DBU

pyridine

4-{2-[5-Methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-benzoic acid hydrazide

4-{2-[5-Methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-benzoic Acid Hydrazide

phenylchloroformate

→

title compound

수율 47.1%

5-(4-{2-[5-Methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-phenyl)-3H-[1,3,4]oxadiazol-2-one

수율 47.1%

용매

ethyl acetate

dichloromethane

반응 조건

후처리

1. 1
   기타is consumed (by TLC analysis)
2. 2
   workup.ADDITIONDilute the mixture with ethyl acetate
3. 3
   세척wash with water
4. 4
   건조brine dry over MgSO4
5. 5
   농축concentrate under reduced pressure
6. 6
   기타Seal the resulting solution
7. 7
   온도warm it to 170° C. in a Personal Chemistry™ microwave oven
8. 8
   workup.STIRRINGstir at this temperature for 120 min
9. 9
   온도Cool
10. 10
    기타the reaction to room temperature
11. 11
    세척wash with 1 M HCl solution (or saturated NaH2PO4 solution)
12. 12
    건조dry over MgSO4
13. 13
    농축concentrate
14. 14
    기타Triturate the resulting residue with dichloromethane several times

실험 절차

To a suspension of: 4-{2-[5-Methyl-2-(4-trifluoromethyl-phenyl)-thiazol-4-yl]-ethoxy}-benzoic acid hydrazide (Example 4, 276 mg, 0.65 mmol) in dichloromethane (4 mL) add pyridine (104 μL, 1.3 mmol) followed by phenylchloroformate (0.88 μL, 0.71 mmol). Stir the resulting mixture at room temperature until all the starting material is consumed (by TLC analysis). Dilute the mixture with ethyl acetate wash with water then brine dry over MgSO4 and concentrate under reduced pressure. Take the residue up in acetonitrile (5 mL). To this mixture, add DBU (106 μL, 0.71 mmol). Seal the resulting solution; warm it to 170° C. in a Personal Chemistry™ microwave oven and stir at this temperature for 120 min. Cool the reaction to room temperature, dilute with ethyl acetate, wash with 1 M HCl solution (or saturated NaH2PO4 solution) dry over MgSO4 and concentrate. Triturate the resulting residue with dichloromethane several times to give the title compound as a tan solid (137 mg). (recrystallized from ethyl acetate in a sealed tube at 140° C.).

출처