Methanesulfonyl chloride → HCID 15077739, compound

Reaction equation

[OH:1][CH2:2][CH2:3][N:4]1[C:8]([NH2:9])=[C:7]([C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:6]=[N:5]1.[CH3:15][S:16](Cl)(=[O:18])=[O:17]>C(Cl)Cl.C(N(CC)CC)C>[CH3:15][S:16]([O:1][CH2:2][CH2:3][N:4]1[C:8]([NH2:9])=[C:7]([C:10]([O:12][CH2:13][CH3:14])=[O:11])[CH:6]=[N:5]1)(=[O:18])=[O:17]

Participants

Procedure

To a solution of 1-(2-hydroxyethyl)-4-ethoxycarbonyl-5-aminopyrazole (200 g) in a mixture of methylene chloride (2 l) and triethylamine (210 ml) was added dropwise methanesulfonyl chloride (85.5 ml) under ice-cooling. The mixture was stirred for 1 hour at 3°-5° C. The reaction mixture was poured into ice-water (700 ml). The separated organic layer was washed with 1N hydrochloric acid and water, and dried over magnesium sulfate. The solvent was evaporated to give 1-(2-methylsulfonyloxyethyl)-4-ethoxycarbonyl-5-aminopyrazole (270.8 g) as crystals.