Lewis acid-driven self-assembly of diiridium macrocyclic catalysts imparts substrate selectivity and glutathione tolerance

Molecular inorganic catalysts (MICs) tend to have solvent-exposed metal centers that lack substrate specificity and are easily inhibited by biological nucleophiles. Unfortunately, these limitations exclude many MICs from being considered for in vivo applications. To overcome this challenge, a strate...

Full description

Saved in:
Bibliographic Details
Published in:Chemical science (Cambridge) 2023-09, Vol.14 (37), p.1264-1272
Main Authors: Nguyen, Hieu D, Jana, Rahul D, Campbell, Dylan T, Tran, Thi V, Do, Loi H
Format: Article
Language:English
Subjects:
Aldehydes
Catalysts
Cations
Chemistry
Crystallography
Glutathione
Iridium
Lewis acid
Nucleophiles
Photon correlation spectroscopy
Self-assembly
Substrate inhibition
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:Molecular inorganic catalysts (MICs) tend to have solvent-exposed metal centers that lack substrate specificity and are easily inhibited by biological nucleophiles. Unfortunately, these limitations exclude many MICs from being considered for in vivo applications. To overcome this challenge, a strategy to spatially confine MICs using Lewis acid-driven self-assembly is presented. It was shown that in the presence of external cations ( e.g. , Li + , Na + , K + , or Cs + ) or phosphate buffered saline, diiridium macrocycles spontaneously formed supramolecular iridium-cation species, which were characterized by X-ray crystallography and dynamic light scattering. These nanoassemblies selectively reduced sterically unhindered C&z.dbd;O groups via transfer hydrogenation and tolerated up to 1 mM of glutathione. In contrast, when non-coordinating tetraalkylammonium cations were used, the diiridium catalysts were unable to form higher-ordered structures and discriminate between different aldehyde substrates. This work suggests that in situ coordination self-assembly could be a versatile approach to enable or enhance the integration of MICs with biological hosts. Addition of metal salts to a diiridium macrocyclic complex leads to the spontaneous formation of supramolecular particles that react preferentially with small substrates and can tolerate glutathione additives.
ISSN:2041-6520
2041-6539
DOI:10.1039/d3sc02836d