Gold Nanocluster Functionalized with Peptide Dendron
Thiolates: Acceleration of the Photocatalytic Oxidation of an Amino
Alcohol in a Supramolecular Reaction Field
Herein,
we report the synthesis of gold nanoclusters (AuNCs) functionalized
by peptide dendron thiolate ligands forming a hydrogen bonding supramolecular
reaction field. The prepared AuNCs act as efficient photocatalysts
that promote the oxidative cyclization of an amino alcohol to afford
the oxazolidine product. Circular dichroism (CD) spectroscopy and 1H NMR titration experiments revealed that the dynamic transformation
of interdendron hydrogen bonds into intermolecular hydrogen bonds
between the ligand and the substrate is the key to accelerating the
photocatalytic reaction. This work introduces a concept for tuning
the reactivities and selectivities of metal nanocluster catalysts
that use supramolecular reaction fields created with dendritic thiolate
ligands.