Dimethylformamide → 3-Chloro-1,2-benzisothiazole

HRID 1183792Notes

Reaction equation

HRID 1183792 reaction equation
[S:1]1[C:5]2[CH:6]=[CH:7][CH:8]=[CH:9][C:4]=2[C:3](=O)[NH:2]1.CN(C)C=O.S(Cl)([Cl:18])=O>ClC1C=CC=CC=1>[Cl:18][C:3]1[C:4]2[CH:9]=[CH:8][CH:7]=[CH:6][C:5]=2[S:1][N:2]=1

Participants

5

Reactant 3

HCID 6228DimethylformamideHCID 175201,2-Benzisothiazol-3(2H)-oneHCID 24386Thionyl Chloride

Product 1

HCID 5981903-Chloro-1,2-benzisothiazoleYield 90%

Reagents, catalysts & solvents 1

HCID 7964ChlorobenzeneSolvent

Procedure

A 1 L four-neck flask equipped with a stirrer, a thermometer and a condenser tube was charged with 75.6 g (0.5 mol) of 1,2-benzisothiazol-3-one, 54.8 g (0.75 mol) of N,N-dimethylformamide and 100.0 g of chlorobenzene. While stirring, 71.4 g (0.6 mol) of thionyl chloride was added dropwise thereto over 1 hour at 70° to 80° C., and the mixture was reacted at the same temperature for 8 hours. After terminating the reaction, the liquid reaction mixture was concentrated, and a crude product obtained was distillated under reduced pressure of 0.93 kPa at 128° C. to give 75.1 g (0.45 mol) of 3-chloro-1,2-benzisothiazole. The yield based on the 1,2-benzisothiazol-3-one was 90%.

Workup

  1. customA 1 L four-neck flask equipped with a stirrer
  2. customthe mixture was reacted at the same temperature for 8 hours
  3. customAfter terminating
  4. customthe reaction
  5. customthe liquid reaction mixture
  6. concentrationwas concentrated
  7. customa crude product obtained
  8. customwas distillated under reduced pressure of 0.93 kPa at 128° C.

Sources & evidence

ORD record
ord-009e201c73bd4121af068eddd04aa4bd
Source dataset
uspto-grants-2014_03
Patent number
US08664404B2

Reaction notes

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