Results 21 to 30 of about 29,362 (316)
Molecules, 2021 Nitroalkanes activated with polyphosphoric acid could serve as efficient electrophiles in reactions with amines and hydrazines, enabling various cascade transformations toward heterocyclic systems.
Alexander V. Aksenov +6 more
doaj +1 more source
Results in Chemistry, 2021 An efficient tetra-n-butyl ammonium peroxydisulphate (TBA)2S2O8 catalyzed a direct one-pot synthesis of fully substituted pyrazoles in excellent yields with high regioselectivity has been described via a three-component cyclocondensation of aldehydes ...
Mallesh Magini +5 more
doaj +1 more source
One-pot preparation of carbamoyl benzotriazoles and their applications in the preparation of ureas, hydrazinecarboxamides and carbamic esters [PDF]
Journal of the Serbian Chemical Society, 2016 Carbamoyl benzotriazoles were conveniently synthesized in one-pot from carboxylic acids, diphenylphosphorazidate (DPPA) and benzotriazole (BtH). The reactivity and applications of carbamoyl benzotriazoles were also explored.
Mao Hui +5 more
doaj +1 more source
1,1,2,2-Tetrakis[(benzoylamino)methyl]hydrazine
Molbank, 2011 We report herein the synthesis of 1,1,2,2-tetrakis[(benzoylamino)methyl]-hydrazine from (benzamidomethyl)triethylammonium chloride and hydrazine monohydrate in the presence of triethylamine in ethanol/aqueous media. The structure of the newly synthesized
Emil Popovski +2 more
doaj +1 more source
Synthesis of aza-phenylalanine, aza-tyrosine, and aza-tryptophan precursors via hydrazine alkylation; pp. 168–178 [PDF]
Proceedings of the Estonian Academy of Sciences, 2015 Aza-amino acid precursors with an aromatic side chain were synthesized using hydrazine alkylation. This synthetic pathway avoided use of hydrogen gas and expensive hydrogenation catalysts. For the optimization of this alkylation reaction various solvents
Anton Mastitski +3 more
doaj +1 more source
Chalcones as versatile synthons for the synthesis of 5- and 6-membered nitrogen heterocylces [PDF]
, 2014 Chalcones belong to the flavonoid family which constitutes one of the major classes of naturally occurring oxygen heterocyclic compounds. The alpha,beta-unsaturated carbonyl system of chalcones possesses two electrophilic reactive centers allowing them ...
Albuquerque, Hélio +3 more
core +1 more source
Hydrazones as Singular Reagents in Asymmetric Organocatalysis [PDF]
, 2016 This Minireview summarizes strategies and developments regarding the use of hydrazones as reagents in asymmetric organocatalysis, their distinct roles in nucleophile–electrophile, cycloaddition, and cyclization reactions.
Fernández Fernández, Rosario Fátima +4 more
core +1 more source
Approaches towards the synthesis of 5-aminopyrazoles
Beilstein Journal of Organic Chemistry, 2011 The biological and medicinal properties of 5-aminopyrazoles have prompted enormous research aimed at developing synthetic routes to these heterocyles. This review focuses on the biological properties associated with this system. Various synthetic methods
Ranjana Aggarwal +3 more
doaj +1 more source
A multistep continuous flow synthesis machine for the preparation of pyrazoles via a metal-free amine-redox process. [PDF]
, 2015 A versatile multistep continuous flow setup is reported for the four-step conversion of anilines into pyrazole products. The synthesis machine incorporates the use of amine-redox chemistry through diazotization and a metal-free vitamin C mediated ...
Browne, Duncan L +2 more
core +5 more sources
Advanced Functional Materials, EarlyView.Cu‐based catalysts as a cornerstone in advancing sustainable energy technologies are fully reviewed in this manuscript, highlighting their potential in photo‐ and electrocatalysis. It includes metallic copper, copper oxides, copper sulfides, copper halide perovskites, copper‐based metal–organic frameworks (MOFs), and covalent organic frameworks (COFs),
Jéssica C. de Almeida +16 more
wiley +1 more source