Acetic Acid → 7-Chloro-2,3-dihydrobenzo[d]isothiazole 1,1-Dioxide

HRID 1709094Notes

Reaction equation

HRID 1709094 reaction equation
[Cl:1][C:2]1[C:10]2[S:9](=[O:12])(=[O:11])[N:8]=[CH:7][C:6]=2[CH:5]=[CH:4][CH:3]=1.[BH4-].[Na+].C(O)(=O)C>C(O)C>[Cl:1][C:2]1[C:10]2[S:9](=[O:12])(=[O:11])[NH:8][CH2:7][C:6]=2[CH:5]=[CH:4][CH:3]=1

Participants

5

Reactant 3

HCID 176Acetic AcidHCID 4311764Sodium borohydrideHCID 136863097-Chloro-1,2-benzisothiazole-1,1-dioxide

Product 1

HCID 136863107-Chloro-2,3-dihydrobenzo[d]isothiazole 1,1-DioxideYield 97.4%

Reagents, catalysts & solvents 1

HCID 702EthanolSolvent

Conditions

Temperature
0 °C

Procedure

A suspension of 17.9 g of 7-chloro-1,2-benzisothiazole-1,1-dioxide in 180 ml of absolute ethanol was cooled to 0° C. and treated with 3.33 g of sodium borohydride at such a rate that the temperature remained below 5° C. The mixture was warmed to room temperature for 30 minutes, recooled to 0° C. and contacted with glacial acetic acid to destroy excess hydride. The mixture was concentrated to dryness, the resulting solid suspended in water, filtered, washed with water and dried in vacuo at 50° C. for 16 hours to give 17.6 g of the title compound as a white powder, m.p. 159°-161° C.

Workup

  1. customremained below 5° C
  2. temperatureThe mixture was warmed to room temperature for 30 minutes
  3. customrecooled to 0° C.
  4. customto destroy excess hydride
  5. concentrationThe mixture was concentrated to dryness
  6. filtrationfiltered
  7. washwashed with water
  8. customdried in vacuo at 50° C. for 16 hours

Sources & evidence

ORD record
ord-b1b79c5e21f64796ab0a75809a4a0564
Source dataset
uspto-grants-1990_08
Patent number
US04948416

Reaction notes

Loading…