Asymmetrische Katalyse über die Ligandensphäre von oktaedrischen Komplexen mit chiralem Metallzentrum

Abstract

Aufgrund der Beziehung zwischen Struktur und Funktion in der Chemie ist der Zugang zu neuartigen chemischen Strukturen ein treibender Faktor für die Entdeckung neuer chemischer Funktionen. Unter diesem Blickwinkel betrachtet, liegt die beachtliche Nützlichkeit der oktaedrischen Geometrie sechsfach koordinierter Metallkomplexe darin begründet, dass ihre stereochemische Vielseitigkeit mit der Fähigkeit gepaart wird, Zugang zu chemischem Raum zu ermöglichen, der für rein organische Verbindungen möglicherweise nicht erreichbar ist. In diesem Kurzaufsatz möchten wir inerte oktaedrische Metallkomplexe mit metallzentrierter Chiralität als aufkommende Klasse metallgestützten asymmetrischer “Organokatalysatoren” vorstellen. Die Ausnutzung der oftmals starren und globulären Gerüste sowie die vielfältige Stereochemie versprechen neue Anwendungsmöglichkeiten auf dem Gebiet der Katalyse.

Synthesis and Characterization of a New Cu (BHB)2/Fe-MIL-101-NH2 Composite: A Novel Hydrogen Peroxide Sensor based upon the Bimetallic Complex

“…3 The structure of Schiff base complexes is exceptionally comparative to metal porphyria complexes using for catalysis. Therefore, there is a wide space of research for Schiff base metal complexes due to their biological and catalytic activity based on many reports such as asymmetric catalysis, 20 olefinic oxidation, 21 Suzuki coupling reactions 22 and hydrogen peroxide sensor. 23 The related outcomes appear that the Schiff base complexes display high catalytic performance.…”

Switchable Stereoselectivity in Bromoaminocyclization of Olefins: Using Brønsted Acids of Anionic Chiral Cobalt(III) Complexes

“…[1] Thec onventional strategy for the establishment of their chirality mostly relies on chiral organic molecular anion catalysts,s uch as borane anions, [2a-b] phosphate anions, [2c-g] and anion-bonding (thio)ureas. [3] Belokon and co-workers have introduced as eries of salicylaldehyde-derived chiral cobalt-(III) complexes as counteranions which are capable of facilitating af ew C À Cb ond formation reactions,a lbeit with low to moderate enantioselectivities. [3] Belokon and co-workers have introduced as eries of salicylaldehyde-derived chiral cobalt-(III) complexes as counteranions which are capable of facilitating af ew C À Cb ond formation reactions,a lbeit with low to moderate enantioselectivities.…”

“…[2h-i] However,the potential of stereochemically stable octahedral chiral metal-complexes as counteranions,i nw hich the metal center does not serve as ac atalytic center to directly activate the substrate by coordination, but just offers ar igid framework and the environment of centrochirality,h as been much less recognized in asymmetric catalysis. [3] Belokon and co-workers have introduced as eries of salicylaldehyde-derived chiral cobalt-(III) complexes as counteranions which are capable of facilitating af ew C À Cb ond formation reactions,a lbeit with low to moderate enantioselectivities. [4] Them ost severe limitation of these cobalt(III) complexes turns out to be the stereocontrolled synthesis of defined meridional stereoisomers.…”

Tris(1,2-diphenylethylenediamine)cobalt(III) Complexes: Chiral Hydrogen Bond Donor Catalysts for Enantioselective α-Aminations of 1,3-Dicarbonyl Compounds

“…During this period, many types of catalyst-based stereogenic elements have been evaluated. We have sought to (1) expand the chiral pool to include inorganic or organometallic molecules that exhibit chiralty motifs not commonly encountered in organic systems and (2) explore the utility of NH hydrogen bond donor groups that are either ligated to the metal or positioned at remote sites. , Related themes have been of interest in the Meggers group. , …”