Water → 6-benzyloxy-2H-1-benzopyran-3-carboxaldehyde

HRID 466175Notes

Reaction equation

HRID 466175 reaction equation
[OH:1][C:2]1[CH:3]=[CH:4][C:5]2[O:10][CH2:9][C:8]([CH:11]=[O:12])=[CH:7][C:6]=2[CH:13]=1.C(=O)([O-])[O-].[K+].[K+].[CH2:20](Br)[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1.O>CN(C=O)C>[CH2:20]([O:1][C:2]1[CH:3]=[CH:4][C:5]2[O:10][CH2:9][C:8]([CH:11]=[O:12])=[CH:7][C:6]=2[CH:13]=1)[C:21]1[CH:26]=[CH:25][CH:24]=[CH:23][CH:22]=1

Participants

6

Reactant 4

HCID 962WaterHCID 7498Benzyl BromideHCID 11430Potassium CarbonateHCID 47708156-Hydroxychromene-3-carboxaldehyde

Product 1

HCID 149712606-benzyloxy-2H-1-benzopyran-3-carboxaldehyde

Reagents, catalysts & solvents 1

HCID 6228DimethylformamideSolvent

Procedure

A mixture of 6-hydroxy-2H-1-benzopyran-3-carboxaldehyde (25.0 g, 0.14 mol) and potassium carbonate (39.2 g, 0.28 mol) in 500 ml of DMF is treated with benzyl bromide (26.7 g, 0.16 mol). The mixture is stirred overnight at room temperature. Water is added and three extractions with dichloromethane are carried out. The extract is dried (MgSO4) and evaporated to dryness. The residue is crystallized from hot ethyl acetate to give 6-benzyloxy-2H-1-benzopyran-3-carboxaldehyde, m.p. 112°-114° C.

Workup

  1. extractionthree extractions with dichloromethane
  2. dry with materialThe extract is dried (MgSO4)
  3. customevaporated to dryness
  4. customThe residue is crystallized from hot ethyl acetate

Sources & evidence

ORD record
ord-12f6cde40e39456691a1140d3910462e
Source dataset
uspto-grants-1992_10
Patent number
US05155130

Reaction notes

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