Phenol → 2-(4-Hydroxyphenyl)-2,4-dimethyl-2H-1,4-benzothiazin-3(4H)-one

HRID 649315Notes

Reaction equation

HRID 649315 reaction equation
[CH3:1][CH:2]1[C:7](=[O:8])[N:6]([CH3:9])[C:5]2[CH:10]=[CH:11][CH:12]=[CH:13][C:4]=2[S:3]1.S(Cl)(Cl)(=O)=O.[C:19]1([OH:25])[CH:24]=[CH:23][CH:22]=[CH:21][CH:20]=1.[Cl-].[Al+3].[Cl-].[Cl-]>C(Cl)Cl>[CH3:1][C:2]1([C:22]2[CH:23]=[CH:24][C:19]([OH:25])=[CH:20][CH:21]=2)[C:7](=[O:8])[N:6]([CH3:9])[C:5]2[CH:10]=[CH:11][CH:12]=[CH:13][C:4]=2[S:3]1

Participants

6

Reactant 4

HCID 996PhenolHCID 24648Sulfuryl chlorideHCID 6451240Aluminum(III) ChlorideHCID 129549032,4-Dimethyl-2H-1,4-benzothiazin-3(4H)-one

Product 1

HCID 142446972-(4-Hydroxyphenyl)-2,4-dimethyl-2H-1,4-benzothiazin-3(4H)-oneYield 90.3%

Reagents, catalysts & solvents 1

HCID 6344DichloromethaneSolvent2×

Procedure

To a stirred solution of 3,4-dihydro-2,4-dimethyl-3-oxo-2H-1,4-benzothiazine (4.8 g) in methylene chloride (25 ml), sulfuryl chloride (3.5 g) is added under ice-cooling. The mixture is stirred for 30 minutes, and added into a solution of phenol (2.4 g) and aluminum chloride (3.3 g) in methylene chloride (20 ml) with stirring under ice-cooling. The mixture is stirred for 1 hour under ice-cooling, and washed with water, saturated aqueous sodium bicarbonate solution and saturated aqueous sodium chloride solution. The solution is dried over anhydrous sodium sulfate and concentrated in vacuo. A mixture of benzene and n-hexane (1:1) is added to the residue and the separated crystals are collected by filtration to give 6.4 g (90.2%) of the titled compound.

Workup

  1. temperaturecooling
  2. stirringwith stirring under ice-
  3. temperaturecooling
  4. stirringThe mixture is stirred for 1 hour under ice-
  5. temperaturecooling
  6. washwashed with water, saturated aqueous sodium bicarbonate solution and saturated aqueous sodium chloride solution
  7. dry with materialThe solution is dried over anhydrous sodium sulfate
  8. concentrationconcentrated in vacuo
  9. additionA mixture of benzene and n-hexane (1:1)
  10. additionis added to the residue
  11. filtrationthe separated crystals are collected by filtration

Sources & evidence

ORD record
ord-56322e03e8b04735a61756a9ddb7dad4
Source dataset
uspto-grants-1988_04
Patent number
US04739050

Reaction notes

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