Potassium Dichromate → 7-Acetamido-2-methylquinoline-5,8-dione

HRID 1760197

Reaction equation

HRID 1760197 reaction equation
[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=[O:2].[K+].[K+].C(N[C:16]1[CH:25]=[C:24]([NH:26][C:27](=[O:29])[CH3:28])[C:23]([O:30]C(=O)C)=[C:22]2[C:17]=1[CH:18]=[CH:19][C:20]([CH3:34])=[N:21]2)(=O)C>C(O)(=O)C.O>[C:27]([NH:26][C:24]1[C:23](=[O:30])[C:22]2[N:21]=[C:20]([CH3:34])[CH:19]=[CH:18][C:17]=2[C:16](=[O:2])[CH:25]=1)(=[O:29])[CH3:28]

Participants

5

Reactant 2

HCID 24502Potassium Dichromate2×HCID 10805264HCID 10805264, compound

Product 1

HCID 98345267-Acetamido-2-methylquinoline-5,8-dioneYield 56%

Reagents, catalysts & solvents 2

HCID 176Acetic AcidSolvent2×HCID 962WaterSolvent2×

Procedure

This compound was prepared by the oxidation of the corresponding acylamido with potassium dichromate in glacial acetic acid. Into a 1000 ml Erlenmeyer flask, 240 ml of glacial acetic acid, and 5,7-diacetamido-2-methyl-8-acetoxyquinoline (31) (prepared as described in Example 31) (6.3 g, 2.0 mmol) were added. To the resulting suspension, a solution of potassium dichromate (17.64 g) in 200 ml of water was added. This black solution was magnetically stirred at room temperature for 20-24 hours. The solution was then poured into 900 ml of water and extracted with dichloromethane (5×200 ml). The organic extracts were washed with a solution of 5% sodium carbonate in a saturated salt solution (3×300 ml). The organic layer was dried overnight with anhydrous magnesium sulfate. The magnesium sulfate was filtered off, and the solvent was evaporated to leave an orange/yellow solid. The solid 7-acetamino-2-methylquinoline-5,8-dione (27) was dried overnight under vacuum. 2.6 g of product was obtained for a yield of 56%.

Workup

  1. extractionextracted with dichloromethane (5×200 ml)
  2. washThe organic extracts were washed with a solution of 5% sodium carbonate in a saturated salt solution (3×300 ml)
  3. dry with materialThe organic layer was dried overnight with anhydrous magnesium sulfate
  4. filtrationThe magnesium sulfate was filtered off
  5. customthe solvent was evaporated
  6. customto leave an orange/yellow solid
  7. dry with materialThe solid 7-acetamino-2-methylquinoline-5,8-dione (27) was dried overnight under vacuum

Sources & evidence

ORD record
ord-dd53a72979104252bc6d414557411f9d
Source dataset
uspto-grants-2005_01
Patent number
US06841555B2

Linked notes

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