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Showing 1 to 8 of 8 for “"Chiral induction"”.
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Synthesis of Chiral Benzimidazolylidenes from 1,10-Phenathrolines and 1,10-Phenathroline-2,9-dione /
… current synthetic approaches. The preparation of chiral analogues is even more challenging. Previously, our group has demonstrated an alternative approach to synthesizing benzimidazolylidenes with a tetracyclic framework in three steps from 1,10-phenanthroline. This thesis is focused on approaches …
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IMPROVING THE SCOPE AND UNDERSTANDING OF THE SYMMETRIC AND ASYMMETRIC SUZUKI COUPLING REACTION
… Suzuki cross-couplings towards axially chiral biaryl products have also been detailed. Model reactions towards configurationally stable biaryl products were found to undergo a successful chiral induction with the use of chiral ferrocenyl ligand (R)-(S)-PPFA 180, with high enantiomeric …
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Investigation of aryldimethylsilanolates in palladium-catalyzed cross-coupling reactions and development of chiral bis-hydrazone ligands for asymmetric aryl-aryl couplings
… of a novel synthetic route to access a number of chiral bis-hydrazone ligands featuring a 2,5-diarylpyrrolidine moiety. This endeavor enables systematic investigation of the ligand effect on the reactivity and enantioselectivity of the reaction. The origin of the chiral induction has been …
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Asymmetric reduction using enzymes and Chiral chemical reagents
… is concerned with the asymmetric reduction of achiral substrates to chiral products on a preparative scale. In the first case dihydrofolate reductase was used to catalyse the conversion of 7,8-dihydrofolic acid into (6S)- 5,6,7, B-tetrahydrofolic acid. The required coenzyme,NADPH, was recycled …
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Optically active [(eta 6 -arene)Cr(CO) 3]-based diphosphines : synthesis and application in asymmetric homogeneous hydrogenation
Chiral diphosphines have become an important class of ligands for asymmetric catalysis. It is the success itself of enantioselective catalysis that has enhanced the demand for new chiral ligands for essentially two reasons. The first one is that no class of ligands can be considered universal …
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Asymmetrische Cycloisomerisierung von 1,6-Dienen
… system is comparable with the most successful achiral protocols. Apart from diethyl diallylmalonate, we were able to transform further 1,6-dienes into the desired exo-methylenecyclopentanes. The highest enantioselectivity was observed with 4,4-bis-(hydroxymehtyl)-1,6-heptadiene as substrate. A …
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Chiral Polymer Photodetector
… is fabricated using polythiophene with chiral alkyl side chains. The Cotton effect is observed in the CD spectrum of the photodetector, indicating an unequal absorbance of left- and right-handed circular polarized light (CPL). The photodetector is proven to be able to identify incident …
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Enantiomerenreine beta-Diketonate für lumineszierende helicat-artige Komplexe
The work bases on ß-diketonates which all bear a chiral spacer and the following complexations lead to enantiomerically pure helicates. All ligands were synthesised by a Claisen-type condensation reaction . During the work a huge number of optimisation attempts of the coupling reaction, as well as …