[Co₄O₄]⁴⁺ Cubane Core as a Brønsted Base:  Preparation and Properties of [Co₄O₃(OH)(O₂CR)₂(bpy)₂]³⁺ and [Co₄O₂(OH)₂(O₂CR)₂(bpy)₂]⁴⁺ Salts

Abstract

The cover picture shows the structure transformation from a well-known gold nanocluster Au 25 (SCH 2 CH 2 Ph) 18 (Au 25 for short) to a novel cadmium doped gold nanocluster [Au 13 Cd 2-(PPh 3) 6 (SC 2 H 4 Ph) 6 (NO 3) 2 ] 2 Cd(NO 3) 4 (Au 26 Cd 5 for short) by a combined peeling and doping process. Although the mother nanocluster Au 25 is inactive, the as-prepared Au 26 Cd 5 exhibits high catalytic activity, as well as good recyclability and sub-strate tolerance at room temperature. The high catalytic activity is attributed to the cooperation between the exerted cadmium atoms and the neighbor gold atoms in the Au 13 icosahedron based on some experimental results. More details are discussed in the article by Wu et al. on page 567-571. REVIEWS 531 This review summarizes the transition metal complex catalyst with high thermal stability. The structures of complex include the backbone of bis(imino)pyridine, α-diimine ligands and other types of ligands. The plausible mechanism on the thermostable catalysts was proposed which gives guidance to design this class of catalyst. Recent Progress on Transition Metal (Fe, Co, Ni, Ti and V) Complex Catalysts in Olefin Polymerization with High Thermal Stability

Pivalates with the MII 4O4 cubane core (M = Co, Ni): synthesis, structure, magnetic properties, and solid-state thermolysis

“…3, a) due appar ently to intermolecular antiferromagnetic exchange interactions. This behavior strongly differs from the magnetic prop erties of the known symmetrical cubane [Co 4 (µ 3 OMe) 4 (µ 2 OOCBu t ) 2 (η 2 OOCBu t ) 2 (MeOH) 4 ]•4MeOH (8), 11 which we synthesized according to the new method by recrystallization of the tetranuclear complex [Co 4 (µ 3 OH) 2 (µ 2 OOCBu t ) 4 (η 2 OOCBu t ) 2 (EtOH) 4 ]•2EtOH with the planar metal core from methanol. 28 According to the results of magnetic measurements, the effective magnetic moment of complex 8 monotoni cally decreases throughout the 300-2 K temperature range from 9.82 to 4.20 µ B due to spin orbital and spin spin antiferromagnetic exchange interactions (Fig.…”

“…Tetra(µ µ µ µ µ 3 hydroxo)tris(η η η η η 1 trimethylacetato)tris(µ µ µ µ µ 4,5 di methyl 1,2 phenylenediamino)tris(η η η η η 1 4,5 dimethyl 1,2 phe nylenediamino)tetracobalt(II) trimethylacetate ethanol and water solvate, [Co 4 (µ µ µ µ µ 3 OH) 4 (η η η η η 1 OOCBu t ) 3 (µ µ µ µ µ (NH 2 ) 2 C 6 H 2 Me 2 ) 3 ( η η η η η 1 (NH 2 ) 2 C 6 H 2 Me 2 ) 3 ] + (OOCBu t ) -•4EtOH•1. 4 (µ 2 OOCBu t ) 2 (η 2 OOCBu t ) 2 (MeOH) 4 ]•4MeOH determined earlier by X ray diffraction. 11 Tetra(µ µ µ µ µ 3 methoxo)bis(µ µ µ µ µ 2 O,O´ trimethylacetato)bis (µ µ µ µ µ 2 O,O´ trimethylacetato)tetra(η η η η η 1 methanol)tetranickel(II) methanol tetrasolvate, [Ni 4 (µ µ µ µ µ 3 OMe) 4 (µ µ µ µ µ 2 OOCBu t ) 2 (η η η η η 2 OO CBu t ) 2 (MeOH) 4 ]•4MeOH (9•4MeOH).…”

“…According to X ray diffraction data, the geometrical characteristics of the {Ni II 4 , which also contains methoxide bridges. The metal atoms in cluster 7 are at nonbonding distances.…”

“…11 Tetra(µ µ µ µ µ 3 methoxo)bis(µ µ µ µ µ 2 O,O´ trimethylacetato)bis (µ µ µ µ µ 2 O,O´ trimethylacetato)tetra(η η η η η 1 methanol)tetranickel(II) methanol tetrasolvate, [Ni 4 (µ µ µ µ µ 3 OMe) 4 (µ µ µ µ µ 2 OOCBu t ) 2 (η η η η η 2 OO CBu t ) 2 (MeOH) 4 ]•4MeOH (9•4MeOH). Methanol (40 mL) was added to the complex [Ni 4 (µ 3 OH) 2 (µ 2 OOCBu t ) 4 (η 2 OOCBu t ) 2 (EtOH) 4 ]•2EtOH (0.3 g, 0.26 mmol), and the mixture was stirred under argon at 60 °C until complete dissolu tion of the starting compound. The green solution was filtered and concentrated at 0.1 Torr and 20 °C to 15-20 mL.…”

Synthesis and Crystal Structure of a Tetranuclear Cubane‐like Nickel(II) Complex with 2‐Hydroxymethyl‐N‐salicylideneaniline

“…2 Tetranuclear cubane-like nickel complexes have been extensively investigated since the pioneering work of Andrew and Blake et al 3 A number of cubanelike tetranuclear nickel complexes involving bridging OH 4 or OMe, 5 or alkoxo 6,7 have been pre-viously reported. Jezowska-Trzebiatowska and coworkers 8 reported a nickel(II) complex of 2-hydroxymethyl-Nsalicylideneaniline (H 2 L), and concluded that the complex had a polynuclear structure.…”