Microwave-assisted one-pot synthesis in water of carbonylpyrazolo[3,4-b]pyridine derivatives catalyzed by InCl<sub>3</sub> and sonochemical assisted condensation with aldehydes to obtain new chalcone derivatives containing the pyrazolopyridinic moiety
Pyrazolo[3,4-b]pyridine derivatives have been synthesized via one-pot condensation of 3-methyl-1-phenyl-1H-pyrazolo-5-amine (1), formaldehyde (as paraformaldehyde) (2) and β-diketones (3) under microwave irradiation in aqueousmedia catalyzed by InCl3. This process has been found to be useful in the preparation of new N-fused heterocycle products in good to excellent yields. Further treatment of pyrazolopyridines
吡唑并[3,4- b ]吡啶衍生物是通过3-甲基-1-苯基-1 H-吡唑并-5-胺(1),甲醛(作为低聚甲醛)(2)和β-的一锅缩合反应合成的。在InCl 3催化的水性介质中微波辐射下的二酮(3)。已经发现该方法可用于以良好至优异的产率制备新的N-稠合的杂环产物。吡咯并吡啶(4a和4e)与醛类芳香族化合物(5a–l)的进一步处理提供了查耳酮类似物。
Synthesis of Newly Substituted Pyrazoles and Substituted Pyrazolo[3,4-<i>b</i>]Pyridines Based on 5-Amino-3-Methyl-1-Phenylpyrazole
作者:Talaat I. El-Emary
DOI:10.1002/jccs.200700072
日期:2007.4
10b was produced through reaction of 9 with acetophenone. Reaction of 1 with benzylidinemalononitrile afforded 11. New methods for preparation of 15 and 16 are described. The reaction of 8 with malononitrile, thio-semicarbazide, phenyl hydrazine and acetophenone afforded compounds 18-21. The reaction of 21 with malononitrile gave 22. Compounds 23-26 were produced upon reaction of 10a with malononitrile