15802-75-2Relevant articles and documents
A mild and efficient method for the regioselective iodination of pyrazoles
Rodríguez-Franco, María Isabel,Dorronsoro, Isabel,Hernández-Higueras, Ana I,Antequera, Gema
, p. 863 - 865 (2001)
The iodination of N-H or N-benzylpyrazoles using elemental iodine in the presence of CAN as the in situ oxidant is a mild and efficient method to prepare 4-iodopyrazoles containing even electron-withdrawing substituents. The reaction is regioselective since the iodine atom preferred pyrazole instead of the benzyl group, and the 4-pyrazolic position instead of other possible positions in the heterocycle.
R4NHal/NOHSO4: A Usable System for Halogenation of Isoxazoles, Pyrazoles, and beyond
Bondarenko, Oksana B.,Karetnikov, Georgy L.,Komarov, Arseniy I.,Pavlov, Aleksandr I.,Nikolaeva, Svetlana N.
supporting information, p. 322 - 332 (2021/01/14)
A new convenient and versatile halogenating system (R4NHal/NOHSO4), giving straightforward and general access to halogenated 3,5-diaryl- and alkylarylisoxazoles, pyrazoles and electron-rich benzenes from the corresponding scaffolds, is suggested. The method provides excellent regioselectivity, scalability to the gram scale, and a broad scope for both aromatics and halogens. A three-step, one-pot reaction protocol was developed, and a series of 3,5-diaryl-4-haloisoxazoles has been efficiently synthesized from 1,2-diarylcyclopropanes under suggested nitrosating-halogenating conditions.
Method for synthesizing 1 - methyl -4 -iodo pyrazole (by machine translation)
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Paragraph 0054-0057, (2020/06/16)
The invention relates to the technical field 1 - methyl -4 - iodinol synthesis, in particular to a synthesis method of 1 - methyl -4 - iodo pyrazole. The synthesis method of 1 - methyl -4 - iodinol comprises the following steps: (1) mixing 1 - methylpyrazole with iodine, heating to 40 - 80 °C, dropwise adding an oxidizing agent aqueous solution to carry out iodination reaction, and (2) adding alkali liquor to 5 - 9 DEG C to obtain a light yellow crystal, namely 1 - methyl -4 - iodo pyrazole. To 1 - methyl -4 - iodinol synthesis method, 1 - methylpyrazole raw materials are used as the iodinating agent, and an oxidizing agent, an oxidizing agent and hydrogen iodide are added to generate iodine, so that iodine is fully utilized, the reaction rate and product yield are improved, and the synthesis cost 1 - methyl -4 -iodo pyrazole is greatly reduced. (by machine translation)
PYRAZOLE DERIVATIVES
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Page/Page column 80, (2017/08/01)
Provided herein are compounds of the formula I: as well as pharmaceutically acceptable salts thereof, wherein the substituents are as those disclosed in the specification. These compounds, and the pharmaceutical compositions containing them, are useful for the treatment or prevention of mGluR5 mediated disorders, such as acute and/or chronic neurological disorders, cognitive disorders and memory deficits, as well as acute and chronic pain.
Electrosynthesis of 4-iodopyrazole and its derivatives
Lyalin,Petrosyan,Ugrak
experimental part, p. 1549 - 1555 (2011/05/04)
Electrosynthesis of 4-iodo-substituted pyrazoles has been accomplished by iodination of the corresponding precursors on a Pt-anode in aqueous solutions of KI under conditions of the diaphragm galvanostatic electrolysis. Efficiency of the process depends on the donor-acceptor properties of substituents and their positions in the pyrazole ring. Thus, iodination of pyrazole, 3,5-dimethylpyrazole, 3-nitropyrazole, 1-methylpyrazole, 1,3-dimethylpyrazole, pyrazole-3(5)-carboxylic acid or methyl esters furnished 4-iodo derivatives in 57, 86, 2, 5, 35, 30, and 40% yields, respectively.
Two-stage sonogashira coupling method in the synthesis of auxin active acetylenes
Wayne Craig,Eberle, Martin,Irminger, Bruno,Schueckenboehmer, Anegret,Laime, Yvette,Mueller, Patrick
, p. 1967 - 1974 (2008/09/16)
A sequential Sonogashira coupling of a protected acetylene precursor with aryl halides (5) followed by pyrazolyl iodides (14) allows efficient access to the unsymmetrical aryl-heteroarylacetylene (8). Subsequent regioselective lithiation exchange followed by dimethyl oxalate quench produced readily vicinal ketoesters (9) which show auxin effects in a wide variety of plant species.
Micelle Activated Reactions I. Micelle Activated Iodination and Partial Dehalogenation of Pyrazoles and 1,2,4-Triazoles
Miethchen, R.,Randow, R.,Listemann, R.,Hildebrandt, J.,Kohlheim, K.
, p. 799 - 805 (2007/10/02)
A method is described to iodinate pyrazole, substituted pyrazoles or 1,2,4-triazole with iodine or iodine chloride in aqueous alkaline in the presence of an anionic surfactant. 4-Iodo- (2a), 4-iodo-3(5)-methyl- (2b), 3(5),4-diiodo- (3a), 3(5),4-diiodo-5(3)-methyl- (3b), and 3,4,5-triiodo-pyrazole (3d) as soon as 4-iodo-pyrazole-3(5)-carboxylic acid (2c), and 3(5)-iodo-1,2,4-triazole (5) were prepared.Anhydrous hydrogen fluoride or triethylamine trishydrofluoride were found to be a suitable agent to effect a regioselective partial dehalogenation of 3b, 3d and 3,5-dibromo-1,2,4-triazole (7).We prepared 3(5)-iodo-5(3)-methyl-pyrazole (6b), 3,5-diiodo-pyrazole (6d) and 3(5)-bromo-1,2,4-triazole (8) on this way.
