7-Hydroxyflavanone → 7-[2-(1H-1-Imidazolyl)ethoxy]-2-phenyl-4-chromanone

HRID 368349Notes

Reaction equation

HRID 368349 reaction equation
[OH:1][C:2]1[CH:11]=[C:10]2[C:5]([C:6](=[O:18])[CH2:7][CH:8]([C:12]3[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=3)[O:9]2)=[CH:4][CH:3]=1.C1(P(C2C=CC=CC=2)C2C=CC=CC=2)C=CC=CC=1.[N:38]1([CH2:43][CH2:44]O)[CH:42]=[CH:41][N:40]=[CH:39]1.N(C(OCC)=O)=NC(OCC)=O>C1COCC1>[N:38]1([CH2:43][CH2:44][O:1][C:2]2[CH:11]=[C:10]3[C:5]([C:6](=[O:18])[CH2:7][CH:8]([C:12]4[CH:17]=[CH:16][CH:15]=[CH:14][CH:13]=4)[O:9]3)=[CH:4][CH:3]=2)[CH:42]=[CH:41][N:40]=[CH:39]1

Participants

6

Reactant 4

HCID 18907-HydroxyflavanoneHCID 11776TriphenylphosphineHCID 74168N-(2-Hydroxyethyl)imidazoleHCID 220568ethyl N-ethoxycarbonyliminocarbamate

Product 1

HCID 154869117-[2-(1H-1-Imidazolyl)ethoxy]-2-phenyl-4-chromanoneYield 43.1%

Reagents, catalysts & solvents 1

HCID 8028TetrahydrofuranSolvent2×

Procedure

A solution of 5.0 g (20.8 mmol) of 7-hydroxy-2-phenyl-4-chromanone in 200 mL of THF was treated with 6.22 g (23.7 mmol) of triphenylphosphine and 2.65 g (23.7 mmol) of 2-(1H-1-imidazolyl)-1-ethanol. A solution of 4.13 g (23.7 mmol) of diethyl azodicarboxylate in 25 mL of THF was added dropwise and the solution allowed to stir at room temperature overnight. The solvent was removed under pressure, and the residue taken up in 1N citric acid and washed three times with Et2O. The aqueous phase was adjusted to pH 7 with 50% NaOH and extracted with EtOAc. The EtOAc was washed with saturated NaCl and dried over MgSO4. Treatment with charcoal and removal of the solvent under pressure gave 3.0 g (43% yield) of the product as a white solid, mp 139-140° C. The structure was confirmed by NMR and mass spectroscopy. MS m/z 335 (M+H+).

Workup

  1. customThe solvent was removed under pressure
  2. washwashed three times with Et2O
  3. extractionextracted with EtOAc
  4. washThe EtOAc was washed with saturated NaCl
  5. dry with materialdried over MgSO4
  6. customTreatment with charcoal and removal of the solvent under pressure

Sources & evidence

ORD record
ord-34f330f749044861aff96ead089fa1a0
Source dataset
uspto-grants-2000_10
Patent number
US06133303

Reaction notes

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