Hydrogen Bromide → 2-bromomethyl-4-isopropyl-6-methoxy-1,2-benzisothiazol-3(2H)-one 1,1-dioxide

HRID 1289828Notes

Reaction equation

HRID 1289828 reaction equation
[CH:1]([C:4]1[C:9]2[C:10](=O)[NH:11][S:12](=[O:14])(=[O:13])[C:8]=2[CH:7]=[C:6]([O:16][CH3:17])[CH:5]=1)([CH3:3])[CH3:2].[CH2:18]=[O:19].[BrH:20]>C(O)(=O)C>[Br:20][CH2:10][N:11]1[C:18](=[O:19])[C:9]2[C:4]([CH:1]([CH3:3])[CH3:2])=[CH:5][C:6]([O:16][CH3:17])=[CH:7][C:8]=2[S:12]1(=[O:13])=[O:14]

Participants

5

Reactant 3

HCID 260Hydrogen BromideHCID 712FormaldehydeHCID 101473624-Isopropyl-6-methoxysaccharin

Product 1

HCID 108825772-bromomethyl-4-isopropyl-6-methoxy-1,2-benzisothiazol-3(2H)-one 1,1-dioxideYield 66%

Reagents, catalysts & solvents 1

HCID 176Acetic AcidSolvent2×

Procedure

To a mixture of 4-isopropyl-6-methoxy-1,2-benzisothiazol-3(2H)-one 1,1-dioxide in acetic acid (20 ml) was added paraformaldehyde (0.7 g, 23.33 mmol), followed by 48% HBr in acetic acid (4.2 ml, 23.45 mmol). The mixture was heated at 50°-55° C. for 4 hours, cooled, poured over ice-water and filtered. The product was purified by column chromatography on silica gel eluting with 10-15% ethyl acetate/hexane to afford 1.88 g (66%) of 2-bromomethyl-4-isopropyl-6-methoxy-1,2-benzisothiazol-3(2H)-one 1,1-dioxide, m.p. 157°-159° C.

Workup

  1. temperatureThe mixture was heated at 50°-55° C. for 4 hours
  2. temperaturecooled
  3. filtrationfiltered
  4. customThe product was purified by column chromatography on silica gel eluting with 10-15% ethyl acetate/hexane

Sources & evidence

ORD record
ord-0fd94fb54f6548b2ba7f86f66e5dcc36
Source dataset
uspto-grants-1998_05
Patent number
US05750550

Reaction notes

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