On April 22, 2021, Chen, Yuzhong; Freudenberger, John Herbert; Wright, James published a patent.SDS of cas: 1187582-58-6 The title of the patent was Methods for the preparation of 5-bromo-2-(3-chloropyridin-2-yl)-2H-pyrazole-3-carboxylic acid. And the patent contained the following:
Described herein are novel methods of synthesizing 5-bromo-2-(3-chloro-pyridin-2-yl)-2H-pyrazole-3-carboxylic acid from pyrazole or pyrazole derivatives For example, protecting pyrazole with 3,4-dihydro-2H-pyrazole followed by bromination of the resulting 1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole, deprotecting (5-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole containing 3-bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole), coupling 3-bromo-1H-pyrazole with 2,3-dichloropyridine, and reacting 2-(3-bromo-1H-pyrazol-1-yl)-3-chloropyridine with CO2 in the presence of TMPMgCl.LiCl solution in THF afforded 5-bromo-2-(3-chloro-pyridin-2-yl)-2H-pyrazole-3-carboxylic acid. General method of preparing compound I [each of R5-R10 = (independently) H and halo; and R13 = an organic acid], starting by halogenation of protected pyrazole II [R14 = (un)substituted carbocycle and heterocycle], was disclosed. The experimental process involved the reaction of 5-Bromo-1-(tetrahydro-2H-pyran-2-yl)-1H-pyrazole(cas: 1187582-58-6).SDS of cas: 1187582-58-6
The Article related to bromochloropyridinylpyrazolecarboxylic acid preparation intermediate, Heterocyclic Compounds (More Than One Hetero Atom): Pyrazoles and other aspects.SDS of cas: 1187582-58-6
Referemce:
Pyrazole – Wikipedia,
Pyrazoles – an overview | ScienceDirect Topics