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Showing 1 to 8 of 8 for “"axial chirality"”.
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Synthesis and utilization of guanidine catalysts for applications directed towards the preparation of butenolide and modified amino acid derivatives
… furanone and benzaldehyde. Incorporating chirality into the guanidine catalyst utilizing a (R)-phenylalaninol auxiliary, generating (R)-2-((5Hdibenzo[ d,t] [1,3 ]diazepin-6(7H)-ylidene ) amino )-3 -phenylpropan-l-ol, demonstrated enantioselectivity for a variety of adducts. Highest …
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Nickel-catalyzed coupling reactions and synthetic studies toward ent-dioxepandehydrothyrsiferol via an epoxide-opening cascade
… allene--aldehyde coupling exploits the axial chirality in 1,3-disubstituted allenes in achieving asymmetric induction. When a chiral allene binds to a transition metal catalyst, the allene establishes a chiral environment around the metal center. This can possibly create a new …
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Synthesis of multicyclic ring systems including an alternate route to Meyers’ lactam derivatives
… high atroposelection through a central C5 to axial chirality transfer. The aim of this project will be directed towards the design of alternative strategies in the synthesis of keto-ester Meyers’ lactam derivatives. Leading on to provide new atropos derivatives bearing different substituents …
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The Development of Asymmetric Palladium-Catalysed Transformations Using Chiral Sulfonated Phosphine Ligands
… variant of SPhos. Notably, sSPhos possesses axial chirality due to the desymmetrisation of the distal ring upon sulfonation. We were subsequently able to develop a high-yielding and facile procedure to access highly enantioenriched sSPhos via the recrystallisation of its salt with protonated …
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Synthese axialchiraler Liganden unter Verwendung des Lacton-Konzepts
Das Phänomen der Axialchiralität von Biarylverbindungen wurde erstmalig 1922 beschrieben. Jedoch wurde die Suche nach stereoselektiven Zugangswegen zu dieser Stoffklasse lange Zeit vernachlässigt, obwohl derartige Verbindungen außergewöhnliche pharmakologische Aktivitäten aufweisen und das …
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Memory of Chirality in 1,4-Benzodiazepin-2-ones
Memory of chirality (MOC) is an emerging strategy in asymmetric synthesis. It has been applied to enolate chemistry, reactions involving carbocation intermediates, and to radical systems. In this strategy the chirality of an enantiopure reactant is transferred to the dynamic chirality of a reactive …
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Structure-Property Relationship of the Two-Photon Circular Dichroism of Compounds with Axial and Helical Chirality
… biaryl derivatives and compounds with helical chirality. In Chapter 2 we present the theoretical-experimental study of the effect of the π-electron delocalization curvature on the TPCD of molecules with axial chirality. The targeted molecules for this part of our investigation were S-BINOL, …