4-Chloro-1,2-dihydro-3H-indazol-3-one(CAS: 787580-87-4)

4-Chloro-1,2-dihydro-3H-indazol-3-one is a crystalline solid with a molecular weight of approximately 218.6 g/mol. It is slightly soluble in water and has good solubility in organic solvents like methanol and ethanol. Chemically, it is relatively stable but can undergo substitution reactions with nucleophiles. It reacts with bases to form salts and can also undergo reduction and oxidation reactions.

4-Chloro-1,2-dihydro-3H-indazol-3-one can be synthesized via a multi-step process involving the condensation of 2-aminoindazol-3-one with thiochloroacetic acid, followed by acid hydrolysis. The reaction involves the use of a Lewis acid as a catalyst to promote the condensation step. The overall yield is moderate, and the method provides good selectivity for the desired product.

4-Chloro-1,2-dihydro-3H-indazol-3-one is primarily used in the pharmaceutical industry as an intermediate in the synthesis of certain drugs. It also finds applications in the chemical sensors industry due to its reactivity and stability. Additionally, it can be used in the preparation of certain materials in the semiconductor and polymer industries.

When handling 4-Chloro-1,2-dihydro-3H-indazol-3-one, it is important to wear appropriate personal protective equipment (PPE), including gloves, goggles, and a laboratory coat. Ensure the work is conducted in a fume hood to minimize inhalation exposure. Proper storage should be in a cool, dry place, away from direct sunlight and heat sources. In case of a spill, use appropriate absorbent materials and follow the safety data sheet (SDS) for disposal instructions.