Triethylamine → 5,6-Dichloro-1-(methylsulphonyl)-benzimidazole

HRID 2420116Notes

Reaction equation

HRID 2420116 reaction equation
[CH3:1][S:2](Cl)(=[O:4])=[O:3].[Cl:6][C:7]1[C:15]([Cl:16])=[CH:14][C:10]2[N:11]=[CH:12][NH:13][C:9]=2[CH:8]=1.C(N(CC)CC)C.Cl.C(N(CC)CC)C>CC(C)=O.O>[Cl:16][C:15]1[C:7]([Cl:6])=[CH:8][C:9]2[N:13]([S:2]([CH3:1])(=[O:4])=[O:3])[CH:12]=[N:11][C:10]=2[CH:14]=1

Participants

7

Reactant 4

HCID 8471TriethylamineHCID 11130Triethylamine hydrochlorideHCID 31297Methanesulfonyl chlorideHCID 3317755,6-Dichloro-1H-benzimidazole

Product 1

HCID 203130445,6-Dichloro-1-(methylsulphonyl)-benzimidazole

Reagents, catalysts & solvents 2

HCID 180AcetoneSolvent2×HCID 962WaterSolvent

Procedure

A solution of methanesulphonyl chloride (60 parts) in acetone (800 parts) was added dropwise to a suspension of 5,6-dichloro-benzimidazole (94 parts) in acetone (240 parts) containing triethylamine (50 parts). A precipitate of triethylamine hydrochloride was observed and the temperature rose to 40° C. The mixture was heated under reflux for 10 minutes and then stirred at room temperature for 20 hours. On pouring into cold water (4000 parts) a solid product precipitated out, which was filtered off, washed with water, dried and recrystallised from acetone (charcoal) to give 5,6-dichloro-1-(methylsulphonyl)-benzimidazole (61 parts) as pale yellow needles, melting point 191°-193° C.

Workup

  1. customrose to 40° C
  2. temperatureThe mixture was heated
  3. temperatureunder reflux for 10 minutes
  4. customprecipitated out
  5. filtrationwhich was filtered off
  6. washwashed with water
  7. customdried
  8. customrecrystallised from acetone (charcoal)

Sources & evidence

ORD record
ord-4a8e25bb60ef4025aae0c947bbe4344a
Source dataset
uspto-grants-1978_08
Patent number
US04109004

Reaction notes

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