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Structural requirements and reaction pathways in condensation reactions of alcohols on MgyAlOx catalysts
(Elsevier, 2000-03)
The effect of composition and of surface properties on alcohol-coupling reactions was studied on MgyAlOx catalysts using C2H5OH or 13CH3OH/1–12C3H7OH mixtures as reactants. Samples with Mg/Al ratios of 0.5–9.0 were obtained ...
Epoxy vitrimers: The effect of transesterification reactions on the network structure
(MDPI AG, 2018-01-03)
Vitrimers are covalently crosslinked polymers that behave as conventional thermosets below the glass transition temperature (Tg) but can flow above a particular temperature, Tv > Tg, by bond exchange reactions. In epoxy ...
Spectrophotometric determination of glycolic acid with chromotropic acid assisted by microwave oven
(Editora Unesp, 2002-01-01)
In this work, a rapid, simple and selective spectrophotometric for the determination of glycolic acid is proposed, This method is based on selective reaction between the formaldehyde splitted off by the glycolic acid, which ...
Estudos sobre o uso de NbCl5 como ácido de Lewis em reações de Povarov
(2011)
The aim of this work was to investigate the use of NbCl5 as Lewis acid in cycloadittion reactions [Reaction Aza-Diels-Alder (Povarov)] between Schiff bases and enol ethers. Comparison of reaction yields, obtained products ...
Solid-phase Petasis multicomponent reaction for the generation of beta-lactams 3-substituted with non-proteinogenic alfa-amino acids
(Elsevier, 2013-07)
An efficient protocol for the rapid generation of libraries of biologically promising b-lactams is described. Key step is a solid-phase based multicomponent Petasis reaction
One-Step Synthesis of Methoxylated Phloroglucinol Derivatives Promoted by Niobium Pentachloride: An Experimental and Theoretical Approach
(2017-06-01)
Phloroglucinol derivatives are an important class of natural compounds featuring the rhodomyrtone derivatives. In this work, the synthesis of compounds with a structure core of rhodomyrtosone I is described using a ...
Chromotropic acid-formaldehyde reaction in strongly acidic media. The role of dissolved oxygen and replacement of concentrated sulphuric acid
(Elsevier B.V., 2003-05-28)
The procedure for formaldehyde analysis recommended by the National Institute for Occupational Safety and Health (NIOSH) is the Chromotropic acid spectrophotometric method, which is the one that uses concentrated sulphuric ...
Chromotropic acid-formaldehyde reaction in strongly acidic media. The role of dissolved oxygen and replacement of concentrated sulphuric acid
(Elsevier B.V., 2003-05-28)
The procedure for formaldehyde analysis recommended by the National Institute for Occupational Safety and Health (NIOSH) is the Chromotropic acid spectrophotometric method, which is the one that uses concentrated sulphuric ...
Sobre a força de ácidos e bases: algumas consideraçõesOn the strength of acids and bases: some considerations
(Sociedade Brasileira de Química, 2008)