Ethanol → 3-Ethoxy-6-methoxybenzo[D]isoxazole

HRID 2105901Notes

Reaction equation

HRID 2105901 reaction equation
O1C2C=CC=C[C:4]=2[CH:3]=N1.[OH:10][C:11]1[C:15]2[CH:16]=[CH:17][C:18]([O:20][CH3:21])=[CH:19][C:14]=2[O:13][N:12]=1.C(O)C.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.CC(OC(/N=N/C(OC(C)C)=O)=O)C>C1COCC1>[CH2:3]([O:10][C:11]1[C:15]2[CH:16]=[CH:17][C:18]([O:20][CH3:21])=[CH:19][C:14]=2[O:13][N:12]=1)[CH3:4]

Participants

7

Reactant 5

HCID 702EthanolHCID 11776TriphenylphosphineHCID 710731,2-BenzisoxazoleHCID 5363146Diisopropyl azodicarboxylateHCID 178487771HCID 178487771, compound

Product 1

HCID 210778053-Ethoxy-6-methoxybenzo[D]isoxazoleYield 44%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent

Procedure

Benzisoxazole from part (b) (193 mg, 1.17 mmol), ethanol (75 μl, 1.29 mmol) and triphenylphosphine (460 mg, 1.75 mmol) were dissolved in anhydrous THF (4 ml) and cooled (0°). Diisopropylazodicarboxylate (345 μl, 1.75 mmol) was added slowly and after 10-15 min the reaction flask was removed from the ice bath and the reaction mixture was stirred at room temperature overnight under an argon atmosphere. The solution was evaporated to dryness and the residue pre-absorbed onto silica, and chromatographed on silica (19 g); eluent: hexane (300 ml), 10-30% ethyl acetate/hexane to give 3-ethoxy-6-methoxy-1,2-benzisoxazole (101 mg, 44%) as white crystals.

Workup

  1. temperaturecooled (0°)
  2. customwas removed from the ice bath
  3. customThe solution was evaporated to dryness
  4. customthe residue pre-absorbed onto silica
  5. customchromatographed on silica (19 g)

Sources & evidence

ORD record
ord-3a68ef2dc0b74ef78c2752362701b8e0
Source dataset
uspto-grants-2009_08
Patent number
US07579465B2

Reaction notes

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