1,2-Dibromoethane → 4-(4-(2-Bromoethoxy)-benzyl)-3-(2,4-dichlorophenyl)-7-methoxy-chromen-2-one

HRID 1296686Notes

Reaction equation

HRID 1296686 reaction equation
[Cl:1][C:2]1[CH:7]=[C:6]([Cl:8])[CH:5]=[CH:4][C:3]=1[C:9]1[C:10](=[O:29])[O:11][C:12]2[C:17]([C:18]=1[CH2:19][C:20]1[CH:25]=[CH:24][C:23]([OH:26])=[CH:22][CH:21]=1)=[CH:16][CH:15]=[C:14]([O:27][CH3:28])[CH:13]=2.[Br:30][CH2:31][CH2:32]Br.C([O-])([O-])=O.[K+].[K+].C(Cl)Cl.O>CC(C)=O>[Br:30][CH2:31][CH2:32][O:26][C:23]1[CH:24]=[CH:25][C:20]([CH2:19][C:18]2[C:17]3[C:12](=[CH:13][C:14]([O:27][CH3:28])=[CH:15][CH:16]=3)[O:11][C:10](=[O:29])[C:9]=2[C:3]2[CH:4]=[CH:5][C:6]([Cl:8])=[CH:7][C:2]=2[Cl:1])=[CH:21][CH:22]=1

Participants

6

Reactant 4

HCID 78391,2-Dibromoethane2×HCID 11430Potassium Carbonate2×HCID 113393373-(2,4-Dichlorophenyl)-4-(4-hydroxybenzyl)-7-methoxychromen-2-oneHCID 21908982Water methylene chloride

Product 1

HCID 589130934-(4-(2-Bromoethoxy)-benzyl)-3-(2,4-dichlorophenyl)-7-methoxy-chromen-2-oneYield 61%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A mixture of 3-(2,4-dichlorophenyl)-4-(4-hydroxybenzyl)-7-methoxy-chromen-2-one (6.4 g, 15.0 mmol), 1,2-dibromoethane (12.9 mL, 149.8 mmol) and K2CO3 (4.14 g, 30 mmol) in acetone (65 mL) was stirred at reflux temperature for 20.5 h. An additional portion of K2CO3 (241.6 mg, 1.75 mmol) and 1,2-dibromoethane (3.2 mL, 37.5 mmol) was added at that time and once more 7.5 h later. Heating was continued for an additional 20 h, for a total reaction time of 48 h. The resultant mixture was cooled to room temperature and poured into CH2Cl2/H2O. The layers were separated, and the aqueous phase was extracted with CH2Cl2 (2×). The combined organic layers were washed with brine (2×) and dried (MgSO4), and the solvent was removed in vacuo. The resultant residue was purified using flash chromatography (300 g silica gel, 4.5:1:1→4:1:1→3:1:1 hexanes:CH2Cl2:AcOEt) to provide the title compound as a white solid (4.851 g, 61%) in addition to recovered starting material (2.054 g, 32%). 1H NMR (300 MHz, CDCl3) δ 7.50 (d, J=2.0 Hz, 1H), 7.44 (d, J=9.0 Hz, 1H), 7.26 (dd, J=2.0, 8.0 Hz, 1H), 7.12 (d, J=8.0 Hz, 1H), 6.98–6.91 (m, 2H), 6.88 (d, J=2.0 Hz, 1H), 6.79–6.74 (m, 3H), 4.23 (t, J=6.5 Hz, 2H), 4.04 (d, J=15.5 Hz, 1H), 3.87 (s, 3H), 3.78 (d, J=15.5 Hz, 1H), 3.61 (t, J=6.5 Hz, 2H); MS (ESI) m/z 532.7 (M+H)+; HPLC tR 8.38 min.

Workup

  1. temperatureat reflux temperature for 20.5 h
  2. temperatureHeating
  3. customThe layers were separated
  4. extractionthe aqueous phase was extracted with CH2Cl2 (2×)
  5. washThe combined organic layers were washed with brine (2×)
  6. dry with materialdried (MgSO4)
  7. customthe solvent was removed in vacuo
  8. customThe resultant residue was purified

Sources & evidence

ORD record
ord-df929075fba74423b94b98c4aa20df85
Source dataset
uspto-grants-2007_07
Patent number
US07247646B2

Reaction notes

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