Switchable selectivity in multicomponent heterocyclizations of acetoacetamides, aldehydes, and 3-amino-1,2,4-triazoles/5-aminopyrazoles
作者:Elena A. Muravyova、Sergey M. Desenko、Roman V. Rudenko、Svetlana V. Shishkina、Oleg V. Shishkin、Yulia V. Sen’ko、Elena V. Vashchenko、Valentin A. Chebanov
DOI:10.1016/j.tet.2011.09.138
日期:2011.12
Multicomponent heterocyclizations of 3-amino-1,2,4-triazoles/5-aminopyrazoles with acetoacetamides and aromatic aldehydes were studied in detail using conventional thermal heating, ultrasonication, and microwave irradiation. Several different synthetic pathways for these cyclocondensations occurring under either kinetic or thermodynamic control were established depending on the temperature regime and building block selection. The experimental data obtained and the procedures developed allow tuning selectivity of the multicomponent reactions studied. (C) 2011 Elsevier Ltd. All rights reserved.
Efficient synthesis of novel functionalized dihydro‑pyrazolo[3,4-d]pyridines via the three-component reaction using MgO/HAp as a sustainable catalyst
作者:Nagaraju Kerru、Lalitha Gummidi、Suresh Maddila、Sreekantha B. Jonnalagadda
DOI:10.1016/j.inoche.2020.108321
日期:2021.1
catalytic activity of MgO/HAp for the synthesis of novel dihydropyrazolo[3,4-b]pyridine derivatives by three-componentreaction of 1H-3-amino-1H-pyrazole, acetoacetanilide and different benzaldehydes in ethanol medium at room temperature (RT). The protocol offered excellent yields (92-97%) of the products in 20-25 min reaction time. Additionally, the spent catalyst was recycled up to five runs without