Dimethyl Sulfate → Methyl 3,4-dimethylbenzothiazol-2-one-5-carboxylate

HRID 1071907Notes

Reaction equation

HRID 1071907 reaction equation
[CH3:1][C:2]1[C:7]2[NH:8][C:9](=[O:11])[S:10][C:6]=2[CH:5]=[CH:4][C:3]=1[C:12]([O:14][CH3:15])=[O:13].[C:16](=O)([O-])[O-].[K+].[K+].S(OC)(OC)(=O)=O>CC(C)=O>[CH3:16][N:8]1[C:7]2[C:2]([CH3:1])=[C:3]([C:12]([O:14][CH3:15])=[O:13])[CH:4]=[CH:5][C:6]=2[S:10][C:9]1=[O:11]

Participants

5

Reactant 3

HCID 6497Dimethyl SulfateHCID 11430Potassium CarbonateHCID 223900755-Benzothiazolecarboxylic acid,2,3-dihydro-4-methyl-2-oxo-,methyl ester

Product 1

HCID 22390078Methyl 3,4-dimethylbenzothiazol-2-one-5-carboxylateYield 84.3%

Reagents, catalysts & solvents 1

HCID 180AcetoneSolvent

Procedure

A solution of 11.38 g (51 mmol) of methyl 4-methylbenzo-thiazol-2-one-5-carboxylate in 400 ml of acetone was admixed with 14.18 g of potassium carbonate. 5.1 ml (54 mmol) of dimethyl sulfate were then added dropwise with stirring, and the mixture was stirred at 23° C. for 78 hours. The precipitated solid was filtered off and the solvent was removed under reduced pressure. Recrystallization from ether gave, in a yield of 84%, 10.15 g (43 mmol) of methyl 3,4-dimethylbenzothiazol-2-one-5-carboxylate of m.p. 97° C.-100° C.

Workup

  1. stirringthe mixture was stirred at 23° C. for 78 hours
  2. filtrationThe precipitated solid was filtered off
  3. customthe solvent was removed under reduced pressure
  4. customRecrystallization from ether

Sources & evidence

ORD record
ord-71473da7c67a41e9a1d48105e5a7d5e1
Source dataset
uspto-grants-2005_06
Patent number
US06908884B2

Reaction notes

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