Facile synthesis of pyrazoles by iron-catalyzed regioselective cyclization of hydrazone and 1,2-diol under ligand-free conditions
作者:Niranjan Panda、Subhadra Ojha
DOI:10.1016/j.jorganchem.2018.02.043
日期:2018.4
A facile synthesis of pyrazoles by the cyclization of hydrazones and 1,2-diols was described. In the presence of ferric nitrate, the reaction occurs under neat conditions and makes the use of potassium persulfate to oxidize the diol to α-hydroxy carbaldehyde for the reaction with hydrazones to produce 1,3- and 1,3,5-substituted pyrazoles selectively. The overall regioselective transformation occurs
Fe-Catalyzed One-Pot Synthesis of 1,3-Di- and 1,3,5-Trisubstituted Pyrazoles from Hydrazones and Vicinal Diols
作者:Niranjan Panda、Ashis Kumar Jena
DOI:10.1021/jo301770k
日期:2012.10.19
An iron-catalyzed route for the regioselectivesynthesis of 1,3- and 1,3,5-substituted pyrazolesfrom the reaction of diarylhydrazones and vicinal diols has been developed. This method was found to be practical with wide substrate scope.
Regioselective Synthesis of C3-Hydroxyarylated Pyrazoles
作者:Leonie O’Sullivan、Ketul V. Patel、Ben C. Rowley、Duncan K. Brownsey、Evgueni Gorobets、Benjamin S. Gelfand、Jeffrey F. Van Humbeck、Darren J. Derksen
DOI:10.1021/acs.joc.1c02518
日期:2022.1.7
report the first regioselective route to C3-hydroxyarylated pyrazoles obtained through reaction of pyrazole N-oxides with arynes using mild conditions. Importantly, this method does not require the C4 and C5 positions of the pyrazole to be functionalized to observe regioselectivity. Using this method, we completed the synthesis of a recently reported JAK 1/2 inhibitor. Our synthesis produces the desired