Matches in DBpedia 2016-04 for { ?s ?p "(Thio)urea organocatalysis describes the utilization of properly designed derivatives of urea and thiourea to accelerate and stereochemically alter organic transformations through predominantly double hydrogen-bonding interactions with the respective substrate(s) (non-covalent organocatalysis). The scope of these small-molecule H-bond donors termed (thio)urea organocatalysts covers both non-stereoselective and stereoselective applications in organic synthesis (asymmetric organocatalysis).In nature non-covalent interactions such as hydrogen bonding (\"partial protonation\") play a crucial role in enzyme catalysis that is characterized by selective substrate recognition (molecular recognition), substrate activation, and enormous acceleration and stereocontrol of organic transformations.Based on the pioneering examinations by Kelly, Etter, Jorgensen, Hine, Curran, Göbel, and De Mendoza (see review articles cited below) on hydrogen bonding interactions of small, metal-free compounds with electron-rich binding sites Schreiner and co-workers performed series of theoretical and experimental systematic investigations towards the hydrogen-bonding ability of various thiourea derivatives.These purely organic compounds were found to reveal significant rate enhancements of simple Diels-Alder reaction, act like weak Lewis acid catalysts, but operate through explicit double hydrogen bonding instead of covalent (strong) binding known from traditional metal-ion mediated catalysis and Brønsted acid catalysis."@en }
Showing triples 1 to 1 of
1
with 100 triples per page.
- Thiourea_organocatalysis abstract "(Thio)urea organocatalysis describes the utilization of properly designed derivatives of urea and thiourea to accelerate and stereochemically alter organic transformations through predominantly double hydrogen-bonding interactions with the respective substrate(s) (non-covalent organocatalysis). The scope of these small-molecule H-bond donors termed (thio)urea organocatalysts covers both non-stereoselective and stereoselective applications in organic synthesis (asymmetric organocatalysis).In nature non-covalent interactions such as hydrogen bonding (\"partial protonation\") play a crucial role in enzyme catalysis that is characterized by selective substrate recognition (molecular recognition), substrate activation, and enormous acceleration and stereocontrol of organic transformations.Based on the pioneering examinations by Kelly, Etter, Jorgensen, Hine, Curran, Göbel, and De Mendoza (see review articles cited below) on hydrogen bonding interactions of small, metal-free compounds with electron-rich binding sites Schreiner and co-workers performed series of theoretical and experimental systematic investigations towards the hydrogen-bonding ability of various thiourea derivatives.These purely organic compounds were found to reveal significant rate enhancements of simple Diels-Alder reaction, act like weak Lewis acid catalysts, but operate through explicit double hydrogen bonding instead of covalent (strong) binding known from traditional metal-ion mediated catalysis and Brønsted acid catalysis.".