A magic‐number Au13 cluster with icosahedral geometry can be exclusively generated from a polydisperse mixture of ultrasmall 1,2‐bis(diphenylphosphino)ethane‐coordinated gold clusters upon treatment ...with HCl, which acts as an efficient promoter.
It is well known that various transition elements can form M···H hydrogen bonds. However, for gold, there has been limited decisive experimental evidence of such attractive interactions. Herein we ...demonstrate an example of spectroscopically identified hydrogen bonding interaction of C-H units to Au atoms in divalent hexagold clusters (Au
) decorated by diphosphine ligands. X-ray crystallography reveals substantially short Au-H/Au-C distances to indicate the presence of attractive interactions involving unfunctionalized C-H moieties. Solution
H and
C NMR signals of the C-H units appear at considerably downfield regions, indicating the hydrogen-bond character of the interactions. The Au···H interactions are critically involved in the ligand-cluster interactions to affect the stability of the cluster framework. This work demonstrates the uniqueness and potential of partially oxidised Au cluster moieties to participate in non-covalent interaction with various organic functionalities, which would expand the scope of gold clusters.Many transition metals can form hydrogen bonds to organic species, but experimental evidence for Au is still lacking. Here, the authors obtain crystallographic and NMR spectroscopic evidence of hydrogen bonding between C-H groups and Au atoms of gold clusters, suggesting that non-covalent interactions may play a role in gold cluster catalysis.
Size matters: The core‐etching reaction by free glutathione is studied for glutathionate (SG)‐protected Aun(SG)m clusters with n=10–39 and m=10–24 (see picture). Only the Au25(SG)18 clusters remain ...unetched, whereas the Aun(SG)m clusters with n<25 and n>25 are transformed into a AuI:SG complex and stable Au25:SG, respectively. The selective synthesis of thiolate (SR)‐protected Au25:SR on a large scale may be possible.
Optically active linear polyurethane and a cyclic dimer were synthesized from 2,7-diisocyanatofluorene and 2,2'-dihydroxy-1,1'-binaphthyl. The circular dichroism (CD) spectral intensity of the ...polymer was amplified at a higher concentration through aggregate formation, while circularly polarized light (CPL) emission was not enhanced. The cyclic dimer's CPL emission was largely amplified (
1.1 × 10
) due to intermolecular excimer formation through aggregation, while the CD intensity was not affected.
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