Synthesis and enantioseparation of chiral Au₁₃ nanoclusters protected by bis-N-heterocyclic carbene ligands

Abstract

A series of chiral Au13 nanoclusters were synthesized via the direct reduction of achiral dinuclear Au(I) halide complexes ligated by ortho-xylyl–linked bis-N-heterocyclic carbene (NHC) ligands. A broad range of functional...

NHC-Stabilized Au10 Nanoclusters and Their Conversion to Au25 Nanoclusters

“…Au–C bond lengths are between 2.026(9) Å and 2.041(9) Å (average 2.034 Å; Table S7 ), which is slightly shorter compared with Au–C NHC bond lengths in previously reported NHC-stabilized gold nanoclusters. 17 − 20 , 23 …”

N-Heterocyclic carbene derivatives to modify gold superatom characteristics. Tailorable electronic and optical properties of [Au11(PPh3)7LCl2]+ as a cluster from relativistic DFT

“…All calculations were carried out at the Relativistic Density Functional Theory level of theory 85 using the ADF code 86 and incorporating scalar corrections via the ZORA Hamiltonian. 87 We employed the triple-ξ Slater basis set, along with two polarization functions (STO-TZ2P) for valence electrons, within the generalized gradient approximation (GGA) according to the Perdew–Burke–Ernzerhof (PBE) exchange–correlation functional 88,89 because of its reliable performance at a reasonable computational cost for similar clusters, 66 thus enabling comparison with other computational studies of medium-sized gold nanoclusters. 90–94 The frozen core approximation was applied to the [1s 2 –4f 14 ] shells for Au, [1s 2 ] for C, and [2s 2 ] for P and Cl, leaving the remaining electrons to be treated variably.…”

“…55–64 Earlier examples include that of Shionoya involving the NHC counterpart of the classical Schmidbauer [C(AuPPh 3 ) 6 ] 2+ cluster and the formation of a [Au 13 (NHC) 9 Cl 3 ] 2+ cluster showing a high emission quantum yield by Crudden, 65 which preceded the characterization and applications of several species. 66–74…”

Synthesis and Vibrational Circular Dichroism Analysis of N-Heterocyclic Carbene Precursors Containing Remote Chirality Centers

“…However, chiroptical data (electronic and vibrational circular dichroism (ECD, VCD), optical rotation) of the NHC precursors were not measured and correlated with the stereochemistry, which would have enabled direct configurational assignment of the synthetic samples. Although there are a few reports on the ECD analysis of NHC precursors and their metal complexes [ 35 , 36 , 37 , 38 ], the VCD approach has not been applied yet to investigate their stereochemistry. Due to the relatively large number of characteristic vibrational transitions associated with the different stereogenic elements, vibrational circular dichroism assisted by DFT calculations was found to be a powerful tool to distinguish more than two stereoisomers for compounds of natural [ 39 , 40 , 41 , 42 ] or synthetic origin [ 43 , 44 , 45 , 46 ].…”