Potassium tert-butoxide → 5-[5-Methyl-1-(4-{[tris(1-methylethyl)silyl]oxy}benzyl)-1H-pyrazol-3-yl]-3-[4-(trifluoromethoxy)phenyl]-1,2,4-oxadiazole

HRID 2400588Notes

Reaction equation

HRID 2400588 reaction equation
[CH3:1][C:2]1[NH:6][N:5]=[C:4]([C:7]2[O:11][N:10]=[C:9]([C:12]3[CH:17]=[CH:16][C:15]([O:18][C:19]([F:22])([F:21])[F:20])=[CH:14][CH:13]=3)[N:8]=2)[CH:3]=1.Br[CH2:24][C:25]1[CH:41]=[CH:40][C:28]([O:29][Si:30]([CH:37]([CH3:39])[CH3:38])([CH:34]([CH3:36])[CH3:35])[CH:31]([CH3:33])[CH3:32])=[CH:27][CH:26]=1.CC(C)([O-])C.[K+]>C1COCC1>[CH3:1][C:2]1[N:6]([CH2:24][C:25]2[CH:26]=[CH:27][C:28]([O:29][Si:30]([CH:31]([CH3:33])[CH3:32])([CH:37]([CH3:39])[CH3:38])[CH:34]([CH3:36])[CH3:35])=[CH:40][CH:41]=2)[N:5]=[C:4]([C:7]2[O:11][N:10]=[C:9]([C:12]3[CH:13]=[CH:14][C:15]([O:18][C:19]([F:20])([F:22])[F:21])=[CH:16][CH:17]=3)[N:8]=2)[CH:3]=1

Participants

5

Reactant 3

HCID 23665647Potassium tert-butoxideHCID 44134296[4-(Bromomethyl)-phenoxy][tris(1-methylethyl)]silane2×HCID 469016545-(5-methyl-1H-pyrazol-3-yl)-3-[4-(trifluoromethoxy)phenyl]-1,2,4-oxadiazole2×

Product 1

HCID 595047665-[5-Methyl-1-(4-{[tris(1-methylethyl)silyl]oxy}benzyl)-1H-pyrazol-3-yl]-3-[4-(trifluoromethoxy)phenyl]-1,2,4-oxadiazoleYield 47%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

To a mechanically stirred solution of 5-(5-methyl-1H-pyrazol-3-yl)-3-[4-(trifluoromethoxy)-phenyl]-1,2,4-oxadiazole (Intermediate C, 600 mg, 1.93 mmol) and [4-(bromomethyl)-phenoxy][tris(1-methylethyl)]silane (Intermediate M, 1.11 g, 2.90 mmol) in dry THF (15 mL) was added potassium tert-butoxide (239 mg, 2.13 mmol) at a temperature of 0° C. The cooling bath was removed, and the reaction mixture was stirred at rt over night. After the addition of water (75 mL), the crude product was extracted into ethyl acetate (3×75 mL). The combined organic extracts were successively washed with water and brine, dried over anhydrous magnesium sulfate, followed by filtration and evaporation of the solvent. The residue was subjected to preparative HPLC to afford the title compound (519 mg, 47%) and, additionally, a considerable amount of the product of the next step (180 mg, 22%) which was formed by cleavage of the silicon-oxygen bond under the acidic HPLC conditions.

Workup

  1. customThe cooling bath was removed
  2. additionAfter the addition of water (75 mL)
  3. extractionthe crude product was extracted into ethyl acetate (3×75 mL)
  4. washThe combined organic extracts were successively washed with water and brine
  5. dry with materialdried over anhydrous magnesium sulfate
  6. filtrationfollowed by filtration and evaporation of the solvent

Sources & evidence

ORD record
ord-f3f4044cc86f4d0e8e4dde120fd6bd38
Source dataset
uspto-grants-2014_08
Patent number
US08796253B2

Reaction notes

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