6647-93-4Relevant articles and documents
New approach to electrochemical iodination of arenes exemplified by the synthesis of 4-iodopyrazoles of different structures
Lyalin,Petrosyan
, p. 360 - 367 (2015/02/05)
The two-stage electrosynthesis of 4-iodosubstituted pyrazole derivatives was performed. At the first stage, KIO3 was obtained at the Ni anode under the undivided galvanostatic conditions of electrolysis of an aqueous alkaline solution of KI (or I2) at the Ni anode. At the second stage, pyrazole and its derivatives were iodinated in the heterophase (H2O-CHCl3 (CCl4)) medium by the KIO3-KI (or KIO3-I2) system in the presence of H2SO4. The yields of iodopyrazoles were 74-92%. The electrochemical iodination of anisole, 2-methylpyrazole, and thiophene was carried out to form 4-iodoanisole (88% yield), 4,5-diiodo-2-methylimidazole (54% yield), and a mixture of 2-iodothiophene (60% yield) and 2,5-diiodothiophene (4% yield).
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.
SYNTHESIS FROM DIMETHYLPYRAZOLES V. NITRATION OF 4-HALOPYRAZOLE-3- AND -5-CARBOXYLIC ACIDS
Manaev, Yu. A.,Andreeva, M. A.,Perevalov, V. P.,Stepanov, B. I.,Dubrovskaya, V. A.,Seraya, V. I.
, p. 2291 - 2296 (2007/10/02)
-
