Benzisothiazole → 3-Chloro-1,2-benzisothiazole

HRID 341976

Reaction equation

HRID 341976 reaction equation
C[S:2][C:3]1[CH:11]=[CH:10][CH:9]=[CH:8][C:4]=1[CH:5]=[N:6]O.S(Cl)([Cl:14])=O.ClCl.S1C2C=CC=CC=2C=N1>ClC1C=CC=CC=1>[Cl:14][C:5]1[C:4]2[CH:8]=[CH:9][CH:10]=[CH:11][C:3]=2[S:2][N:6]=1

Participants

6

Reactant 4

HCID 9225BenzisothiazoleHCID 24386Thionyl ChlorideHCID 24526ChlorineHCID 7867572-(Methylthio)benzaldehyde oxime

Product 1

HCID 5981903-Chloro-1,2-benzisothiazoleYield 96.1%

Reagents, catalysts & solvents 1

HCID 7964ChlorobenzeneSolvent

Procedure

In a 300 ml four-necked flask equipped with a stirrer, a thermometer, and a condenser, 100 g of monochlorobenzene was placed in advance, to which 33.4 g (0.2 mol) of 2-(methylthio)benzaldehyde oxime was added under nitrogen atmosphere. 25.2 g (0.21 mol) Of thionyl chloride was added dropwise thereto while stirring at a temperature of from -10° to -15° C. and allowed to react for 1 hour at the same temperature. After the termination of the reaction, 15.6 g (0.22 mol) of chlorine was continuously blown into the reaction mixture containing 1,2-benzisothiazole while stirring at a temperature of from 70° to 80° C. and allowed to react for 1 hour at the same temperature. After the termination of the reaction, the reaction mixture was subjected to distilling off of the solvent and then to distillation under reduced pressure to give 32.6 g of 3-chloro-1,2-benzisothiazole. The yield was 96% to the 2-(methylthio)benzaldehyde oxime.

Workup

  1. customIn a 300 ml four-necked flask equipped with a stirrer
  2. additionwas added under nitrogen atmosphere
  3. customto react for 1 hour at the same temperature
  4. stirringwhile stirring at a temperature of from 70° to 80° C.
  5. customto react for 1 hour at the same temperature
  6. customAfter the termination of the reaction
  7. distillationto distilling off of the solvent
  8. distillationto distillation under reduced pressure

Sources & evidence

ORD record
ord-5452ffc334694ae09b9bc88857992547
Source dataset
uspto-grants-1999_01
Patent number
US05856504

Linked notes

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