16492-64-1Relevant articles and documents
Synthesis of 4-Organoselanyl-1H-pyrazoles: Oxone -Mediated Electrophilic Cyclization of α,β-Alkynyl Hydrazones by Using Diorganyl Diselenides
Perin, Gelson,Nobre, Patrick C.,Mailahn, Daniela H.,Silva, Márcio S.,Barcellos, Thiago,Jacob, Raquel G.,Lenard?o, Eder J.,Santi, Claudio,Roehrs, Juliano A.
, p. 2293 - 2304 (2019/05/24)
A simple and efficient method for the synthesis of 4organoselanyl-1 H -pyrazoles has been developed, taking place under metal- and halogen-free conditions. Electrophilic species of selenium were easily generated in situ by the reaction of diorganyl diselenides with Oxone in ethanol as solvent in an open-flask at 70 °C. These electrophilic selenium species were employed in the selenylation/cyclization of α,β-alkynyl hydrazones, giving the title compounds in moderate to excellent yields. The final species of selenium obtained from the reaction of diphenyl diselenide with Oxone were characterized by 77 Se NMR spectroscopy and high-resolution mass spectrometry (HRMS).
PTSA-catalyzed Mannich-type-cyclization-oxidation tandem reactions: One-pot synthesis of 1,3,5-substituted pyrazoles from aldehydes, hydrazines and alkynes
Liu, Pei,Pan, Ying-Ming,Xu, Yan-Li,Wang, Heng-Shan
supporting information; experimental part, p. 4696 - 4698 (2012/08/08)
A convenient one-pot Mannich-type-cyclization-oxidation tandem process has been developed for the synthesis of 1,3,5-trisubstituted pyrazoles derivatives from aldehydes, hydrazines and alkynes using p-toluenesulfonic acid monohydrate (PTSA) as a multifunctional catalyst. This method provides a flexible and rapid route to 1,3,5-trisubstituted pyrazoles.
