Salicylamide → 2,2-dibutyl-4-oxo-2,3-dihydro-4H-1,3-benzoxazine

HRID 1781186

Reaction equation

HRID 1781186 reaction equation
[CH2:1]([C:5]([CH2:7][CH2:8][CH2:9][CH3:10])=[O:6])[CH2:2][CH2:3][CH3:4].[C:11]([NH2:20])(=[O:19])[C:12]1[C:13](=[CH:15][CH:16]=[CH:17][CH:18]=1)O.O.C1(C)C=CC(S(O)(=O)=O)=CC=1>C1(C)C=CC=CC=1>[CH2:1]([C:5]1([CH2:7][CH2:8][CH2:9][CH3:10])[NH:20][C:11](=[O:19])[C:12]2[CH:13]=[CH:15][CH:16]=[CH:17][C:18]=2[O:6]1)[CH2:2][CH2:3][CH3:4]

Participants

5

Reactant 3

HCID 5147SalicylamideHCID 104055-NonanoneHCID 521998p-Toluenesulfonic acid monohydrate

Product 1

HCID 100840172,2-dibutyl-4-oxo-2,3-dihydro-4H-1,3-benzoxazineYield 92.5%

Reagents, catalysts & solvents 1

HCID 1140TolueneSolvent

Procedure

A mixture of 20 g of dibutylketone, 19.3 g of salicylamide and 2.7 g of p-toluenesulfonic acid monohydrate is added to 300 ml of toluene and the mixture is refluxed overnight by making use of a dehydrator of Dean Stark. After cooling, the reaction mixture is washed, dried and evaporated to remove the solvent. The residue is purified by silica gel column chromatography (solvent; hexane:ethyl acetate=95:5) to obtain 34 g of 2,2-dibutyl-4-oxo-2,3-dihydro-4H-1,3-benzoxazine as a yellow oil.

Workup

  1. temperaturethe mixture is refluxed overnight
  2. temperatureAfter cooling
  3. washthe reaction mixture is washed
  4. customdried
  5. customevaporated
  6. customto remove the solvent
  7. customThe residue is purified by silica gel column chromatography (solvent; hexane:ethyl acetate=95:5)

Sources & evidence

ORD record
ord-ef0f13707ef34c53bd28617536850e4e
Source dataset
uspto-grants-1997_05
Patent number
US05631363

Linked notes

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