Solvent-Induced Isomeric Cu₁₃ Nanoclusters: Chlorine to Copper Charge Transfer Boosting Molecular Oxygen Activation in Sulfide Selective Oxidation

Abstract

Isomers with minimal structural dissimilarities are promising research objects to obtain a comprehensive understanding of structure−property relationships; however, comparability of isomeric structures is a prerequisite. Herein, two quasi-structurally isomeric 13-nuclei copper nanoclusters (Cu NCs) (Cu13a and Cu13b) containing highly similar Cu 13 kernels and different arrangements of peripheral ligands were obtained using a solvent-induced strategy. The exotic chloride ion is shown to play a prominent role in inducing the selective formation of two quasi-isomers, where the comparative study to establish a structure−property relationship was realized. Due to the charge transition from chlorine to the copper core (X (Cl) M (Cu) CT), the molecular oxygen activation of Cu13a showed higher singlet oxygen ( 1 O 2 ) and lower superoxide radical (O 2•− ) yields compared to those of Cu13b, which gives it better catalytic selectivity for the 1 O 2 involved selective oxidation of sulfides. The present work not only offers a controllable strategy for the rational design and synthesis of quasi-structurally isomeric Cu NCs but also provides a pathway to boost catalytic selectivity by a halogen to metal core charge transition.

Atomically precise copper nanoclusters as ultrasmall molecular aggregates: Appealing compositions, structures, properties, and applications

“…Sun et al have reported two quasi-structurally isomeric CuNCs of [Cu(I) 13 Na 2 (CZ-PrA) 6 (TC 4 A) 2 Cl(MeOH) 2 ] (CuNC-32a) and [Cu(I) 13 Na(CZ-PrA) 6 (TC 4 A) 2 (MeOH)]⋅ MeOH⋅DCM⋅CH 3 COCH 3 (CuNC-32b), where CZ-PrAH = 9-(prop-2-yn-1-yl)-9H-carbazole and H 4 TC4A = p-tertbutylthiacalix[4]arene, as shown in Figure 18A-a,b. [68] The Cu 13 kernel is built from a Cu 5 trigonal bipyramid sharing an equatorial Cu atom with a Cu 5 square pyramid, and the other two equatorial Cu atoms each is appended by two more Cu atoms (Figure 18A-c). In contrast, the Cu 5 trigonal bipyramid in CuNC-32a is more geometrically deformed due to a bridging Clion.…”

Elongation of a Trigonal-Prismatic Copper Cluster by Diphosphine Ligands with Longer Spacers

“…Compared to gold­(I) and silver­(I) clusters, copper­(I) clusters are more synthetically challenging because they are oxidation-sensitive. However, copper complexes are much cheaper than their congeners and always have good photophysical properties. − The construction of copper­(I) clusters mainly includes two strategies: (i) applying copper­(I) precursors directly; , (ii) using comproportionation reactions by mixing copper­(II) salts with copper powders. − Reductions of copper­(II) salts by reducing agents are also good alternatives for the preparation of copper­(I) clusters, which may allow for the serendipity of copper hydride clusters with diverse structures and applications in catalysis, hydrogen storage, and so on. − The protecting ligands of copper hydride clusters include phosphines, − alkynyls, dithiocarbamates, , dithiophosphates, − thiols, − selenols, and carbenes . Alkynyls have been demonstrated to be a kind of versatile ligand in the formation of coin-metal nanoclusters with diverse coordination modes. , However, only a few reports of copper hydride clusters involve alkynyls. ,, Mixed-ligand-protected metal clusters were reported to exhibit higher stability and enhanced properties compared to single-ligand-protected ones .…”

Structure and assembly of a hexanuclear AuNi bimetallic nanocluster

“…metal nanoclusters' crystal structures have been reported. Among them, structural units such as the 13-metal-atom icosahedron (M 13 ), [21][22][23] the 8-metal-atom cube (M 8 ), [24][25][26] and the 4-metal-atom tetrahedron (M 4 ) [27][28][29] are not only stable cluster forms, but also building blocks in hierarchically structured nanoclusters.…”

“…Since the pioneering works on the structural determination of Au 102 (SC 6 H 4 COOH) 44 18 and Au 25 (SC 2 H 4 Ph) 18 , 19,20 hundreds of metal nanoclusters’ crystal structures have been reported. Among them, structural units such as the 13-metal-atom icosahedron (M 13 ), 21–23 the 8-metal-atom cube (M 8 ), 24–26 and the 4-metal-atom tetrahedron (M 4 ) 27–29 are not only stable cluster forms, but also building blocks in hierarchically structured nanoclusters.…”