13745-17-0 | 4-Bromo-1h-pyrazole-3-carboxylic acid

Packsize	Purity	Availability	Price	Discounted Price
250mg	98%	in stock	$6.00	$4.00
1g	98%	in stock	$7.00	$5.00
5g	95%	in stock	$14.00	$10.00
10g	95%	in stock	$25.00	$18.00

Description

• Catalog Number: AA50718
• Chemical Name: 4-Bromo-1h-pyrazole-3-carboxylic acid
• CAS Number: 13745-17-0
• Molecular Formula: C4H3BrN2O2
• Molecular Weight: 190.9828
• MDL Number: MFCD01459882
• SMILES: OC(=O)c1n[nH]cc1Br

Computed Properties

• Complexity: 130
• Covalently-Bonded Unit Count: 1
• Heavy Atom Count: 9
• Hydrogen Bond Acceptor Count: 3
• Hydrogen Bond Donor Count: 2
• Rotatable Bond Count: 1
• XLogP3: 0.8

Upstream Synthesis Route

Starting with commercially available 1H-pyrazole-3-carboxylic acid, the upstream synthetic route to 4-bromo-1H-pyrazole-3-carboxylic acid typically involves a halogenation reaction. The most common method for the bromination is the electrophilic bromination using a brominating agent like N-bromosuccinimide (NBS) in the presence of a radical initiator such as azobisisobutyronitrile (AIBN) or peroxides, and a solvent like carbon tetrachloride (CCl4) or dichloromethane (DCM) at a temperature ranging from room temperature to reflux conditions.

The reaction proceeds via radical formation where the weak N-Br bond in NBS undergoes homolytic cleavage to generate bromine radicals. These bromine radicals react with the pyrazole ring at the position 4 due to its higher electron density. The carboxylic acid group is typically not affected under these reaction conditions.

Careful control of reaction conditions — including temperature, concentration, and stoichiometry of NBS — is crucial to avoid over-bromination and to ensure a good yield of the monobrominated product.

Once the bromination is completed, the reaction mixture is generally quenched with water, and the product is separated, typically using extraction techniques, followed by purification through crystallization or column chromatography to give the pure 4-bromo-1H-pyrazole-3-carboxylic acid.