Search

A bowl-shaped phosphangulene-protected cubic Cu58 nanocluster has been synthesized. The structure was determined by X-ray crystallography and further analyzed by multiple techniques. The phosphangulenes not only enable ligand substitutions with triphenylphosphines in a cluster-to-cluster transformation way, but also facilitate inter-cluster interactions with fullerenes. These interactions further influence the entirety's photocurrent response and ability to liberate hydrogen when stimulated by light. [ABSTRACT FROM AUTHOR]

Structurally precise metal nanoclusters with a facile synthetic process and high catalytic performance have been long pursued. These atomically precise nanocatalysts are regarded as model systems to study structure-performance relationships, surface coordination chemistry, and the reaction mechanism of heterogeneous metal catalysts. Nevertheless, the research on silver-based nanoclusters for driving chemical transformations is sluggish in comparison to gold counterparts. Herein, we report the one-step synthesis of Pt/Ag alloy nanoclusters of [PtAg9(C18H12Br3P)7Cl3](C18H12Br3P), which are highly active in catalysing cycloaddition reactions of CO2 and epoxides. The cluster was obtained in a rather simple way with the reduction of silver and platinum salts in the presence of ligands in one pot. The molecular structure of the titled cluster describes the protection of the Pt-centred Ag9 crown by the shell of phosphine ligands and halides. Its electronic structure, as revealed by density function theoretical calculations, adopts a superatomic geometry with 1S21P6 configuration. Interestingly, the cluster displays high activity in the formation of cyclic carbonates from CO2 under mind conditions. [ABSTRACT FROM AUTHOR]

Photocatalytic organic conversion is considered an efficient, environmentally friendly, and energy-saving strategy for organic synthesis. In recent decades, the molecular cage has emerged as a creative functional material with broad applications in host–guest recognition, drug delivery, catalysis, intelligent materials and other fields. Based on the unique properties of porous molecular cage materials, they provide an ideal platform for leveraging pre-structuring in catalytic reactions and show great potential in various photocatalytic organic reactions. As a result, they have emerged as promising alternatives to conventional molecules or inorganic photocatalysts in redox processes. In this Review, the synthesis strategies based on coordination cages and organic cages, as well as their recent progress in photocatalytic organic conversion, are comprehensively summarized. Finally, we deliver the persistent challenges associated with porous molecular cage compounds that need to be overcome for further development in this field. [ABSTRACT FROM AUTHOR]

Developing hierarchical ordered systems is challenging. Using organo-macrocycles to construct metal–organic frameworks (MOFs) and porous coordination cages (PCCs) provides an efficient way to obtain hierarchical assemblies. Macrocycles, such as crown ethers, cyclodextrins, calixarenes, cucurbiturils, and pillararenes, can be incorporated within MOFs/PCCs and they also endow the resultant composites with enhanced properties and functionalities. This review summarizes recent developments of organo-macrocycle-containing hierarchical MOFs/PCCs, emphasizing applications and structure–property relationships of these hierarchically porous materials. This review provides insights for future research on hierarchical self-assembly using macrocycles as building blocks and functional ligands to extend the applications of the composites. [ABSTRACT FROM AUTHOR]

The identification of hydride(s) in gold nanoclusters is a challenging task, due to the instability of gold nanoclusters containing hydrides. Herein, we report two ultrastable hydrido gold nanoclusters protected by phosphine ligands: [Au20(PPh3)12H3](SbF6)3 (1H) and [Au20(PPh3)12H2(2-COOH-PhS)](PF6)3 (2H). The presence of hydrides in gold(0)–gold(I) nanoclusters is clearly demonstrated by ESI mass spectrometry and NMR spectroscopy. Single crystal structural determination reveals that both nanoclusters have an unprecedented Au20 core consisting of a Au9 unit and a Au11 unit. Such cores derived from the connection of different basic units are important for understanding the evolution and stability of metal nanoclusters. The hydride (H−) was also verified by a charge distribution calculation. [ABSTRACT FROM AUTHOR]

We report the total structure determination of a covalently bonded nanocluster polymer [Au7Ag9(dppf)3(CF3CO2)7BF4]n (1). This features a one-dimensional linear chain, consisting of unique molecular building blocks, Au7Ag8(dppf)3(CF3CO2)7 clusters, which are linked together by Ag–O bonds rather than Au–Au interactions or bidentate organic bridges as previously reported. [ABSTRACT FROM AUTHOR]

An alkynyl-protected gold nanocluster [Au40(PhC≡C)20(dppm)4](SbF6)4 (dppm = bis(diphenylphosphino)methane) (1) has been synthesized. Single-crystal X-ray diffraction reveals that the cluster has a face-centered cubic (FCC) Au34 kernel that is made up of two Au20 units via sharing a rectangular face. Two linear PhC≡C–Au–C≡CPh staple motifs are located around the central part of the Au34 core, and four L-shaped PhC≡C–Au–P^P staple motifs are located at the four corners of the Au34 core. Cluster 1 and [Au38(PhC≡C)20(PPh3)4](CF3SO3)2 both have the FCC Au34 core, and it is found that the diphosphine ligands bringing two more Au atoms into the system have significant effects on the optical properties and stability of the clusters. The combination of a diphosphine ligand and an alkynyl ligand is helpful in generating new ligand-protected metal nanoclusters. [ABSTRACT FROM AUTHOR]

Gold(i) phosphinopyridyl clusters [Au9(PNC)6](BF4)3 (1) and [Au11(PNC)6(PPh3)2](BF4)5 (2) (PNC = 2-diphenylphosphinopyridyl monoion) are assembled. In contrast to the green luminescence of 1, 2 is brightly orange emissive in CH2Cl2, which shows the presence of unsupported AuI–AuI interactions in solution. Besides, 1 and 2 can selectively light up the mitochondria of living cells. [ABSTRACT FROM AUTHOR]

A gold(i)–silver(i) cluster bearing six carboxylate groups has been synthesized through the oxidation of its aldehyde precursor and the Au6 core of this cluster displays an octahedral or a trigonal prismatic configuration depending on the crystallization conditions. The reversible interconversion between these two isomers can be triggered in the solid state by the addition or removal of acetonitrile solvent molecules. Interestingly, luminescence changes were observed as each configuration shows different emission colors, yellow for octahedral type and red for the trigonal prismatic one. [ABSTRACT FROM AUTHOR]

We report a unique intercluster compound comprising a Ag41 cage encapsulating a divacant [α-SiW10O37]10− anion and a complete [β-SiW12O40]4− anion as a counteranion. Two electro-redox centers associated with the inner and outer POM anions show interesting electrochemical behaviours, because the stable Ag41 cage acts as an electron transfer mediator. [ABSTRACT FROM AUTHOR]

A convenient method for the synthesis of silver alkynyl compounds containing different nuclearities has been developed. The reaction of AgC≡CBut and AgX (X = CF3CO2−, C2F5CO2−) in the presence of auxiliary ligands L (L = bipyridine, bipy; 1,10-phenanthroline, phen; 2-(diphenylphosphino)pyridine, dppy) under different conditions afforded a family of new silver alkynyl compounds, namely, [Ag3(bipy)(C≡CBut)(CF3CO2)2]n (1), [Ag4(bipy)2(C≡CBut)(CF3CO2)3]n (2), [Ag6(phen)3(C≡CBut)2(C2F5CO2)4(MeOH)(EtOH)] (3), [Ag8L4(C≡CBut)2(C2F5CO2)6] (L = bipy, 4; L = phen, 5), [Ag10(dppy)2(C≡CBut)6X4] (X = CF3CO2−, 6; X = C2F5CO2−, 7), [Ag12(bipy)2(C≡CBut)8(C2F5CO2)4] (8) and [Ag12(phen)4(C≡CBut)6(CF3CO2)6]·2EtOH (9). Single-crystal X-ray analysis revealed that compounds 1 and 2 display infinite-chain structures, while the other seven compounds are discrete molecules containing silver nuclearities varying from 6 to 12. The formation of various structural motifs depends on the reactant ratios and the ligands/anions with different nature. [ABSTRACT FROM AUTHOR]

We report a unique intercluster compound comprising a Ag41 cage encapsulating a divacant [α-SiW10O37]10− anion and a complete [β-SiW12O40]4− anion as a counteranion. Two electro-redox centers associated with the inner and outer POM anions show interesting electrochemical behaviours, because the stable Ag41 cage acts as an electron transfer mediator. [ABSTRACT FROM AUTHOR]

A bowl-shaped phosphangulene-protected cubic Cu 58 nanocluster has been synthesized. The structure was determined by X-ray crystallography and further analyzed by multiple techniques. The phosphangulenes not only enable ligand substitutions with triphenylphosphines in a cluster-to-cluster transformation way, but also facilitate inter-cluster interactions with fullerenes. These interactions further influence the entirety's photocurrent response and ability to liberate hydrogen when stimulated by light.

Structurally precise metal nanoclusters with a facile synthetic process and high catalytic performance have been long pursued. These atomically precise nanocatalysts are regarded as model systems to study structure-performance relationships, surface coordination chemistry, and the reaction mechanism of heterogeneous metal catalysts. Nevertheless, the research on silver-based nanoclusters for driving chemical transformations is sluggish in comparison to gold counterparts. Herein, we report the one-step synthesis of Pt/Ag alloy nanoclusters of [PtAg 9 (C 18 H 12 Br 3 P) 7 Cl 3 ](C 18 H 12 Br 3 P), which are highly active in catalysing cycloaddition reactions of CO 2 and epoxides. The cluster was obtained in a rather simple way with the reduction of silver and platinum salts in the presence of ligands in one pot. The molecular structure of the titled cluster describes the protection of the Pt-centred Ag 9 crown by the shell of phosphine ligands and halides. Its electronic structure, as revealed by density function theoretical calculations, adopts a superatomic geometry with 1S 2 1P 6 configuration. Interestingly, the cluster displays high activity in the formation of cyclic carbonates from CO 2 under mind conditions.

Photocatalytic organic conversion is considered an efficient, environmentally friendly, and energy-saving strategy for organic synthesis. In recent decades, the molecular cage has emerged as a creative functional material with broad applications in host-guest recognition, drug delivery, catalysis, intelligent materials and other fields. Based on the unique properties of porous molecular cage materials, they provide an ideal platform for leveraging pre-structuring in catalytic reactions and show great potential in various photocatalytic organic reactions. As a result, they have emerged as promising alternatives to conventional molecules or inorganic photocatalysts in redox processes. In this Review, the synthesis strategies based on coordination cages and organic cages, as well as their recent progress in photocatalytic organic conversion, are comprehensively summarized. Finally, we deliver the persistent challenges associated with porous molecular cage compounds that need to be overcome for further development in this field.

For the first time site-specific doping of silver into a spherical Au 25 nanocluster has been achieved in [Au 19 Ag 6 (MeOPhS) 17 (PPh 3 ) 6 ] (BF 4 ) 2 (Au 19 Ag 6 ) through a dual-ligand coordination strategy. Single crystal X-ray structural analysis shows that the cluster has a distorted centered icosahedral Au@Au 6 Ag 6 core of D 3 symmetry, in contrast to the I h Au@Au 12 kernel in the well-known [Au 25 (SR) 18 ] - (R = CH 2 CH 2 Ph). An interesting feature is the coexistence of [Au 2 (SPhOMe) 3 ] dimeric staples and [P-Au-SPhOMe] semi-staples in the title cluster, due to the incorporation of PPh 3 . The observation of only one double-charged peak in ESI-TOF-MS confirms the ordered doping of silver atoms. Au 19 Ag 6 is a 6e system showing a distinct absorption spectrum from [Au 25 (SR) 18 ] - , that is, the HOMO-LUMO transition of Au 19 Ag 6 is optically forbidden due to the P character of the superatomic frontier orbitals., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

We report the total structure determination of a covalently bonded nanocluster polymer [Au7Ag9(dppf)3(CF3CO2)7BF4]n (1). This features a one-dimensional linear chain, consisting of unique molecular building blocks, Au7Ag8(dppf)3(CF3CO2)7 clusters, which are linked together by Ag-O bonds rather than Au-Au interactions or bidentate organic bridges as previously reported.

An alkynyl-protected gold nanocluster [Au40(PhC[triple bond, length as m-dash]C)20(dppm)4](SbF6)4 (dppm = bis(diphenylphosphino)methane) (1) has been synthesized. Single-crystal X-ray diffraction reveals that the cluster has a face-centered cubic (FCC) Au34 kernel that is made up of two Au20 units via sharing a rectangular face. Two linear PhC[triple bond, length as m-dash]C-Au-C[triple bond, length as m-dash]CPh staple motifs are located around the central part of the Au34 core, and four L-shaped PhC[triple bond, length as m-dash]C-Au-P^P staple motifs are located at the four corners of the Au34 core. Cluster 1 and [Au38(PhC[triple bond, length as m-dash]C)20(PPh3)4](CF3SO3)2 both have the FCC Au34 core, and it is found that the diphosphine ligands bringing two more Au atoms into the system have significant effects on the optical properties and stability of the clusters. The combination of a diphosphine ligand and an alkynyl ligand is helpful in generating new ligand-protected metal nanoclusters.

We report a unique intercluster compound comprising a Ag41 cage encapsulating a divacant [α-SiW(10)O37](10-) anion and a complete [β-SiW(12)O40](4-) anion as a counteranion. Two electro-redox centers associated with the inner and outer POM anions show interesting electrochemical behaviours, because the stable Ag41 cage acts as an electron transfer mediator.