Triethylamine → 2-oxo-2H-1-benzopyran-7-yl 4-(but-3-enyloxy)-benzoate

HRID 1532417Notes

Reaction equation

HRID 1532417 reaction equation
[CH2:1]([O:5][C:6]1[CH:14]=[CH:13][C:9]([C:10]([OH:12])=[O:11])=[CH:8][CH:7]=1)[CH2:2][CH:3]=[CH2:4].S(Cl)(Cl)=O.O[C:20]1[CH:29]=[C:28]2[C:23]([CH:24]=[CH:25][C:26](=[O:30])[O:27]2)=[CH:22][CH:21]=1.C(N(CC)CC)C>CN(C=O)C.ClCCl>[CH2:1]([O:5][C:6]1[CH:14]=[CH:13][C:9]([C:10]([O:12][C:20]2[CH:21]=[CH:22][C:23]3[CH:24]=[CH:25][C:26](=[O:30])[O:27][C:28]=3[CH:29]=2)=[O:11])=[CH:8][CH:7]=1)[CH2:2][CH:3]=[CH2:4]

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 24386Thionyl ChlorideHCID 5444524-(3-Butenyloxy)benzoic acidHCID 5281426Umbelliferone

Product 1

HCID 212518322-oxo-2H-1-benzopyran-7-yl 4-(but-3-enyloxy)-benzoateYield 64.4%

Reagents, catalysts & solvents 2

HCID 6228DimethylformamideCatalystHCID 6344DichloromethaneSolvent

Procedure

4.85 g (0.025 mol of 4-(but-3-enyloxy)-benzoic acid were treated with 9 ml of thionyl chloride and 2 drops of DMF and boiled under reflux for 2 hours. The excess thionyl chloride was removed completely, firstly in a water-jet vacuum and subsequently in a high vacuum. The acid chloride remaining was taken up in 10 ml of dichloromethane and slowly added dropwise at 0° C. to a suspension of 3.9 g (0.024 mol) of 7-hydroxy-coumarin and 3.9 ml of triethylamine in 5 ml of dichloromethane. The batch was stirred at room temperature overnight, filtered and the filtrate was evaporated. For purification, the residue was chromatographed on silica gel wiith dichloromethane and subsequently recrystallized from ethanol. There were isolated 5.2 g of 2-oxo-2H-1-benzopyran-7-yl 4-(but-3-enyloxy)-benzoate in the form of fine white needles; m.p. 108-109° C.

Workup

  1. temperatureunder reflux for 2 hours
  2. customThe excess thionyl chloride was removed completely, firstly in a water-jet vacuum and subsequently in a high vacuum
  3. filtrationfiltered
  4. customthe filtrate was evaporated
  5. customFor purification
  6. customthe residue was chromatographed on silica gel wiith dichloromethane
  7. customsubsequently recrystallized from ethanol

Sources & evidence

ORD record
ord-70b00b9e8cf44ea2a951ddbf97295878
Source dataset
uspto-grants-2001_03
Patent number
US06201087B1

Reaction notes

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