Diisopropyl Ether → 4'-Bromo-3'-sulfamoyl-diazoacetophenone

HRID 461151Notes

Reaction equation

HRID 461151 reaction equation
[N:1]([N:3]([CH3:7])C(N)=O)=O.C(OC(C)C)(C)C.[OH-].[K+].[Br:17][C:18]1[CH:26]=[CH:25][C:21]([C:22](Cl)=[O:23])=[CH:20][C:19]=1[S:27](=[O:30])(=[O:29])[NH2:28]>C(OCC)(=O)C.C(OCC)C>[Br:17][C:18]1[CH:26]=[CH:25][C:21]([C:22](=[O:23])[CH:7]=[N+:3]=[N-:1])=[CH:20][C:19]=1[S:27](=[O:29])(=[O:30])[NH2:28]

Participants

7

Reactant 4

HCID 7914Diisopropyl EtherHCID 12699N-Methyl-N-nitrosoureaHCID 14797Potassium Hydroxide2×HCID 213166124-Bromo-3-sulfamoylbenzoyl chloride2×

Product 1

HCID 543259114'-Bromo-3'-sulfamoyl-diazoacetophenone

Reagents, catalysts & solvents 2

HCID 3283Diethyl EtherSolventHCID 8857Ethyl AcetateSolvent

Procedure

26 g of freshly prepared N-nitroso-N-methyl urea were introduced portionwise at 0° to -5° C into a stirred two-phase mixture of 200 ml of diethyl ether (or diisopropyl ether) and 80 ml of 40% aqueous potassium hydroxide solution, the ice-cold etheral diazomethane solution was separated in the separating funnel and dried over a small amount of solid potassium hydroxide at -10° C during 3 hours. The dry solution of the diazomethane in diethyl ether (or diisopropyl ether) was cooled to -5° C to -10° C in a 500 ml three-neck flask provided with stirrer, inner thermometer and KOH drying tube. A suspension of 16.8 g of 4-bromo-3-sulfamoylbenzoyl chloride was added in small portions into 40 ml of anhydrous ethyl acetate, the temperature of the reaction mixture not being allowed to exceed +5° C. After the addition of 4-bromo-3-sulfamoylbenzoyl chloride stirring was continued for another 10 minutes at +5° C and the fair yellow crystalline precipitate of 4'-bromo-3'-sulfamoyl-diazoacetophenone was filtered off. The 4'-bromo-3'-sulfamoyl-diazoacetophenone so obtained was introduced without further purification in small portions into a stirred mixture cooled to 0° C of 30 ml of diethylene glycol dimethyl ether and 20 ml of concentrated HCl (37%). After nitrogen development had finished, stirring was continued for another 10 minutes at 0° C, 150 ml of water were added and after dwelling for 1 hour at 0° C the crystalline precipitate of 4'-bromo-3'-sulfamoyl-2-chloroacetophenone was filtered off. Colorless crystals, melting point: 152° C.

Workup

  1. customthe ice-cold etheral diazomethane solution was separated in the separating funnel
  2. dry with materialdried over a small amount of solid potassium hydroxide at -10° C during 3 hours
  3. temperatureThe dry solution of the diazomethane in diethyl ether (or diisopropyl ether) was cooled to -5° C to -10° C in a 500 ml three-neck flask
  4. customprovided with stirrer
  5. customto exceed +5° C
  6. filtrationthe fair yellow crystalline precipitate of 4'-bromo-3'-sulfamoyl-diazoacetophenone was filtered off

Sources & evidence

ORD record
ord-e350ffeee07c4ceab409a0e37599a73d
Source dataset
uspto-grants-1977_12
Patent number
US04061761

Reaction notes

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