Formaldehyde → 2-(Chloromethyl)-4-isopropyl-6-methoxybenzo[D]isothiazol-3(2H)-one 1,1-dioxide

HRID 1769024Notes

Reaction equation

HRID 1769024 reaction equation
[CH2:1]=[O:2].Cl[Si](C)(C)C.[Sn](Cl)(Cl)(Cl)[Cl:9].[CH:13]([C:16]1[CH:26]=[C:25]([O:27][CH3:28])[CH:24]=[C:23]2[C:17]=1[C:18](=O)[NH:19][S:20]2(=[O:22])=[O:21])([CH3:15])[CH3:14]>ClCCCl.O>[Cl:9][CH2:18][N:19]1[C:1](=[O:2])[C:17]2[C:23](=[CH:24][C:25]([O:27][CH3:28])=[CH:26][C:16]=2[CH:13]([CH3:15])[CH3:14])[S:20]1(=[O:22])=[O:21]

Participants

7

Reactant 4

HCID 712FormaldehydeHCID 6397ChlorotrimethylsilaneHCID 24287Tin tetrachlorideHCID 101473624-Isopropyl-6-methoxysaccharin

Product 1

HCID 99951732-(Chloromethyl)-4-isopropyl-6-methoxybenzo[D]isothiazol-3(2H)-one 1,1-dioxideYield 87%

Reagents, catalysts & solvents 2

HCID 111,2-DichloroethaneSolventHCID 962WaterSolvent

Procedure

To a suspension of 24 g of paraformaldehyde (0.8 mole) and 86.4 g of chlorotrimethylsilane (1.6 moles) in 200 mL of 1,2-dichloroethane was added 0.8 ml anhydrous tin(IV) chloride and the resulting solution stirred on a steam bath for one hour. 4-Isopropyl-6-methoxysaccharin (51.4 g, 0.2 mole) was added to the clear solution and the mixture was refluxed for 18 hours, cooled to room temperature and poured into water. The organic layer was separated, washed with 50 mL of 2N sodium hydroxide solution, dried over anhydrous magnesium sulfate and concentrated under vacuum. The residue was purified by crystallization from ethyl acetate/hexane to give 57 g (87%) of 2-chloromethyl-4-isopropyl-6-methoxysaccharin, m.p. 151 ° C.

Workup

  1. temperaturethe mixture was refluxed for 18 hours
  2. customThe organic layer was separated
  3. washwashed with 50 mL of 2N sodium hydroxide solution
  4. dry with materialdried over anhydrous magnesium sulfate
  5. concentrationconcentrated under vacuum
  6. customThe residue was purified by crystallization from ethyl acetate/hexane

Sources & evidence

ORD record
ord-85c541bfcf0240e591b2c42235625d98
Source dataset
uspto-grants-1995_01
Patent number
US05380737

Reaction notes

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