Exploiting Octahedral Stereocenters: From Enzyme Inhibition to Asymmetric Photoredox Catalysis

Abstract

A simple concept, namely exploiting the structural and stereochemical complexity of octahedral metal complexes, can have unexpected impact in different areas of chemical research, from medicinal chemistry and chemical biology to asymmetric catalysis and photoredox chemistry.

Syntheses, Characterization, Resolution, and Biological Studies of Coordination Compounds of Aspartic Acid and Glycine

“…No separation was observed on the ion-exchange column for Na[Cu(L 1 ) 3 ] and Na[Ni(L 1 ) 3 ], pointing to the fact that geometric isomers are diastereomers and may be separated by physical means. Therefore, it is probable that such isomers may have been separated during preparation or purification [ 7 , 28 , 29 , 39 , 52 , 62 ].…”

“…This is not totally unexpected as the compounds were synthesized using asymmetric synthesis via chiral pool syntheses. Previous researches have shown that products obtained from such reactions are enantiomerically enriched in favour of the chiral starting material [ 7 , 29 , 38 , 76 ]. In the case of the glycinato complexes, the specific rotation was zero, suggestive of a racemic mixture [ 10 , 28 , 29 ].…”

Acyl‐Imidazoles: A Privileged Ester Surrogate for Enantioselective Synthesis

“…In 2014, Meggers and co-workers introduced octahedral iridium (III) and rhodium (III) as a new class of chiral Lewis acid catalysts. [24] The general structure of these cationic complexes is relatively simple and contains only two cyclometallated benzoxazole or benzothiazole achiral ligands in addition to the two labile coordinated acetonitriles. These complexes that exclusively display octahedral metal centrochirality (Λ or Δ) are configurationally stable (Scheme 18).…”

Ligand-centred redox activation of inert organoiridium anticancer catalysts

“…3,4 Third-row 5d 6 iridium(III) complexes offer potential structural diversity of octahedral coordination geometry, slow ligand exchange kinetics, and facile synthesis. [5][6][7] For example, kinetically-inert octahedral iridium pyridocarbazole scaffolds can act as selective protein kinase inhibitors, 8 and inert iridium polypyridine anticancer complexes can have targets other than DNA. 9 Also, inert bis-cyclometalated iridium complexes are promising photosensitizers for singlet oxygen production, 10,11 and a diselenobenzoquinone iridium complex which targets cytochrome P450 reductase, exhibits comparable potency to cisplatin.…”