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Showing 1 to 4 of 4 for “"nucleophilic carbene"”.
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Neue Heterazoliumsalze aus Prolin und Pyroglutaminsäure und Anwendungen in Carben-katalysierten asymmetrischen nucleophilen Acylierungen
… active species of these reactions is a nucleophilic carbene. Consequently, enzyme mimetic asymmetric catalytic processes that are mediated by nucleophilic carbenes in vitro as, for instance, the benzoin condensation, the Stetter and other related nucleophilic acylation reactions have …
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Bicyclische Triazoliumsalze als Präkatalysatoren in der asymmetrischen Benzoin- und Acyloinkondensation und asymmetrische Synthese von Oxazolidin-2-onen
… in the form of the corresponding Wanzlick carbene in the asymmetric variant of the benzoin condensation is described. The chiral bicyclic triazolium salt is currently the most efficient precatalyst for the asymmetric benzoin condensation. The substituted acyloins are obtained in moderate to …
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Development of a catalytic enantioselective intramolecular Stetter reaction: catalyst development and synthetic applications
A triazolinylidene carbene-catalyzed enantioselective intramolecular Stetter reaction has been developed. The process involves direct conversion of an aldehyde into a chiral acyl anion equivalent and its addition into a pendant electron-deficient olefin. The development of chiral bicyclic …
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Carbene catalyzed asymmetric nucleophilic acylations with novel triazolium salts
… (S)-glutamic acid. With access to the new precarbene catalysts we started to verify their ability to promote the benzoin condensation and intramolecular Stetter reaction. The optimal conditions were identified and allowed for an expansion of the reaction scope with 8-95% yield and enantiomeric …