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Sperm guidance in mammals - An unpaved road to the egg
(Nature Publishing Group, 2006-04-01)
Contrary to the prevalent view, there seems to be no competition in the mammalian female genital tract among large numbers of sperm cells that are racing towards the egg. Instead, small numbers of the ejaculated sperm cells ...
Anti-Selective Organocatalytic Michael Addition between Phenylacetaldehyde and Nitrostyrene
(American Chemical Society, 2016-09)
Using the reaction between phenylacetaldehyde and nitrostyrene catalyzed by pyrrolidine as a simple model, we have studied the diastereochemical outcome of the organocatalytic Michael reactions between benzylic aldehydes ...
In situ generation of n-butanethiol and its reaction with electron-deficient olefines
(TAYLOR & FRANCIS INC, 2008)
n-Butanethiol is generated in situ by sequential addition of n-butyllithium and water to elemental sulfur. The n-butanethiol formed was reacted with electron-deficient olefines to give Michael-type addition products in ...
Quantitative characterization of the global philicity patterns of common diene/dienophile pairs in cycloaddition reactions II: the interacting pair model
(Elsevier, 2015)
We present a unified model of electrophilicity and nucleophilicity that considers the electrophile/nucleophile
pair in an interacting regime, thereby avoiding the arbitrariness of defining them as the opposite
ends of a ...
Preparação e utilização de amino catalisadores, derivados do glicerol e aminoácidos, em reações de formação de ligação carbono-carbono
(Universidade Federal de Juiz de Fora (UFJF)BrasilICE – Instituto de Ciências ExatasPrograma de Pós-graduação em QuímicaUFJF, 2019)
Conjugate additions and organocatalytic sequential reactions - new approaches to old reactions
(Universidade Federal de São CarlosUFSCarPrograma de Pós-Graduação em Química - PPGQCâmpus São Carlos, 2016-04-01)
This thesis consists in a collection of projects wherein the focus is
the application of organocatalysts to accelerate the reactions, its primary function,
as to induce asymmetry to the synthetic targets, within a ...
Synthesis of benzylidenecycloalkan-1-ones and 1,5-diketones under Claisen–Schmidt reaction: Influence of the temperature and electronic nature of arylaldehydes
(Taylor & Francis, 2017-12)
Herein, we present the results of the influence of reaction temperature and the electronic nature of arylaldehydes in the reactions of benzocycloalkan-1-ones and arylaldehydes under classical Claisen–Schmidt condensation ...
Estudo sobre o uso do pentacloreto de nióbio, como ácido de Lewis, na síntese de enaminas através da reação de adição de Michael
(Universidade Estadual Paulista (Unesp), 2013)
The NbCl5 being a strong electrophile, is a potential candidate to act as a Lewis acid, and therefore it mediates various organic reactions. For this reason, it has received continuous attention by Brazilian researchers, ...