Acetic Anhydride → 7-(Acetyloxy)-4-methyl-8-(2-propen-1-yl)-2H-1-benzopyran-2-one

HRID 848154Notes

Reaction equation

HRID 848154 reaction equation
[CH2:1]([C:4]1[C:5]([OH:16])=[CH:6][CH:7]=[C:8]2[C:13]=1[O:12][C:11](=[O:14])[CH:10]=[C:9]2[CH3:15])[CH:2]=[CH2:3].[C:17]([O-])(=[O:19])[CH3:18].[Na+].C(OC(=O)C)(=O)C>O>[C:17]([O:16][C:5]1[C:4]([CH2:1][CH:2]=[CH2:3])=[C:13]2[C:8]([C:9]([CH3:15])=[CH:10][C:11](=[O:14])[O:12]2)=[CH:7][CH:6]=1)(=[O:19])[CH3:18]

Participants

5

Reactant 3

HCID 7918Acetic AnhydrideHCID 517045Sodium AcetateHCID 57131038-allyl-7-hydroxy-4-methyl-chromen-2-one

Product 1

HCID 129004497-(Acetyloxy)-4-methyl-8-(2-propen-1-yl)-2H-1-benzopyran-2-oneYield 94%

Reagents, catalysts & solvents 1

HCID 962WaterSolvent

Procedure

A solution of 8-allyl-7-hydroxy-4-methylcoumarin (61.0 g, 0.282 mol) and a few pinches of anhydrous sodium acetate in boiling acetic anhydride (480 ml.) was allowed to relux for four hours with magnetic stirring. The cooled brown mixture was then poured into water (1750 ml.) with magnetic stirring. The mixture was allowed to stir for half an hour. A brown precipitate was collected by filtration, washed with water, and dried in vacuo to obtain 7-acetoxy-4-methyl-8-allylcoumarin (68.5 g. 94% yield), mp. 98.8°-99.8° C. (lit.2 87°-87.5° C.).

Workup

  1. filtrationA brown precipitate was collected by filtration
  2. washwashed with water
  3. customdried in vacuo

Sources & evidence

ORD record
ord-62d852d16966462f948a303ddc151888
Source dataset
uspto-grants-1981_10
Patent number
US04294847

Reaction notes

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