(4-CHLORO-5-METHYL-PYRAZOL-1-YL)-ACETIC ACID synthesis

Yield:180741-45-1 100%

Reaction Conditions:

with N-chloro-succinimide in acetonitrile at 80; for 1.5 h;

Steps:

47.a

a) A mixture of 2-(5-methylpyrazol-1-yl)acetic acid (0.700 g, 5 mmol) and NCS (0.668 g, 5 mmol) in CH₃CN (10 mL) was heated at 80° C. for 1.5 hrs. It was then cooled to rt, evaporated in vacuo, and purified by flash chromatography (SiO₂, with a gradient elution of 0-20% MeOH/CH₂Cl₂) to afford 2-(4-chloro-5-methylpyrazol-1-yl)acetic acid (0.870 g, 100%).

References:

US2014/57937,2014,A1 Location in patent:Paragraph 0237; 0238