Potassium Dichromate → 5-[3,6-Dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-carboxylic acid

HRID 1274614Notes

Reaction equation

HRID 1274614 reaction equation
[Cr](O[Cr]([O-])(=O)=O)([O-])(=O)=[O:2].[K+].[K+].[CH3:12][N:13]1[C:18]([C:19]([F:22])([F:21])[F:20])=[CH:17][C:16](=[O:23])[N:15]([C:24]2[CH:25]=[CH:26][C:27]3[S:31][N:30]=[C:29]([CH:32]=[O:33])[C:28]=3[CH:34]=2)[C:14]1=[O:35]>S(=O)(=O)(O)O.C(O)(=O)C.O>[CH3:12][N:13]1[C:18]([C:19]([F:20])([F:21])[F:22])=[CH:17][C:16](=[O:23])[N:15]([C:24]2[CH:25]=[CH:26][C:27]3[S:31][N:30]=[C:29]([C:32]([OH:2])=[O:33])[C:28]=3[CH:34]=2)[C:14]1=[O:35]

Participants

6

Reactant 2

HCID 24502Potassium DichromateHCID 178523685-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1, 2-benzisothiazole-3-carboxaldehyde

Product 1

HCID 111878605-[3,6-Dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-carboxylic acidYield 67.8%

Reagents, catalysts & solvents 3

HCID 176Acetic AcidSolventHCID 962WaterSolventHCID 1118Sulfuric AcidSolvent

Procedure

A solution of potassium dichromate (10.0 g) in 1.5 M sulfuric acid (200 mL) is cooled to 0° C., treated dropwise with a solution of a 2:3 mixture of 3-[3-(hydromethyl)-1,2-benzisothiazol-5-yl]-1-methyl-6-(trifluoromethyl)-2,4(1H,3H)-pyrimidinedione and 5-[3,6-dihydro-3-methyl-2,6-dioxo-4-(trifluoromethyl)-1(2H)-pyrimidinyl]-1,2-benzisothiazole-3-carboxaldehyde (12.0 g) in acetic acid, stirred at room temperature for 2 hours, and diluted with water. The resultant aqueous mixture is extracted with methylene chloride. The organic extracts are combined, washed sequentially with water and brine, dried over anhydrous sodium sulfate, and concentrated in vacuo to give the title product as a white solid (8.50 g, mp 149-152° C.).

Workup

  1. extractionThe resultant aqueous mixture is extracted with methylene chloride
  2. washwashed sequentially with water and brine
  3. dry with materialdried over anhydrous sodium sulfate
  4. concentrationconcentrated in vacuo

Sources & evidence

ORD record
ord-50cae551cddb4cf8ac54d8ea1354bcf1
Source dataset
uspto-grants-2000_12
Patent number
US06156700

Reaction notes

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