Water → 5-Amino-1-(2-carbamoyloxyethyl)pyrazole

HRID 248335Notes

Reaction equation

HRID 248335 reaction equation
C([NH:3][C:4]1[N:8]([CH2:9][CH2:10][OH:11])[N:7]=[CH:6][CH:5]=1)=O.ClS([N:16]=[C:17]=[O:18])(=O)=O.O.[OH-].[Na+]>C(#N)C>[NH2:3][C:4]1[N:8]([CH2:9][CH2:10][O:11][C:17](=[O:18])[NH2:16])[N:7]=[CH:6][CH:5]=1

Participants

6

Reactant 4

HCID 962WaterHCID 14798Sodium Hydroxide2×HCID 70918Chlorosulfonyl isocyanateHCID 150777375-Formamido-1-(2-hydroxyethyl)pyrazole

Product 1

HCID 229167665-Amino-1-(2-carbamoyloxyethyl)pyrazole

Reagents, catalysts & solvents 1

HCID 6342AcetonitrileSolvent

Procedure

To a suspension of 5-formamido-1-(2-hydroxyethyl)pyrazole (1 g) in acetonitrile (50 ml) was added dropwise chlorosulfonyl isocyanate (0.77 ml) at -15° C.~-20° C. The mixture was stirred for 3 hours under ice-cooling. To the reaction mixture was added water (1 ml) and kept to stand overnight. The solution was adjusted to pH 7.5 with 5N-sodium hydroxide solution and then adjusted to pH 8.5 with 1N-sodium hydroxide solution. The organic layer was separated and the aqueous layer was extracted with tetrahydrofuran. The extract and said organic layer were combined and dried over magnesium sulfate. The solvent was distilled off and the residue was crystallized from ethyl acetate to give 5-amino-1-(2-carbamoyloxyethyl)pyrazole (0.60 g).

Workup

  1. temperaturecooling
  2. waitto stand overnight
  3. customThe organic layer was separated
  4. extractionthe aqueous layer was extracted with tetrahydrofuran
  5. extractionThe extract
  6. dry with materialdried over magnesium sulfate
  7. distillationThe solvent was distilled off
  8. customthe residue was crystallized from ethyl acetate

Sources & evidence

ORD record
ord-ba21085b21494e3c97f10d1abe502e0d
Source dataset
uspto-grants-1993_05
Patent number
US05210080

Reaction notes

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