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A series of homoleptic Ni bis‐1,1‐dithiolates, [Ni(S2C2RR′)2]2− (R=CN, R′=CN, CO2Et, CONH2, Ph, Ph‐4‐Cl, Ph‐4‐OMe, Ph‐4‐NO2, Ph‐3‐CF3, Ph‐4‐CF3, Ph‐4‐CN; R=NO2, R′=H; R=R′=CO2Et) have been synthesized from the reaction of the alkali metal salt of the ligand and nickel chloride, and isolated as tetraphenylphosphonium or tetrabutylammonium salts. The complexes were characterized by X‐ray crystallography, high‐resolution mass spectrometry, and infrared (IR), nuclear magnetic resonance (NMR) and electronic absorption spectroscopies. The molecular structures show a rigidly square planar Ni(II) center linking two four‐membered chelate rings whose dimensions are constant across the series. The electronic effect of the ligand substituent is revealed in the 13C NMR and electronic spectra, and corroborated by density functional calculations. Electron withdrawing groups deshield the low‐field CS2 resonance, and the signature charge transfer band in the visible region is red‐shifted. These observables have been accurately reproduced computationally, and revealed the Ni contribution to the ground state diminishes with decreasing electron withdrawing capacity of the ligand substituent. In contrast to 1,2‐dithiolates, the redox inactivity afforded by 1,1‐dithiolates stems from the smaller chelate ring and substantially reduced sulfur content that is key to stabilizing the radical form. [ABSTRACT FROM AUTHOR]

The preparation and characterization of a new family of four polyoxothiometalate (POTM) clusters are reported, with varying size and complexity, based upon the dimeric [Mo2O2S2(H2O)6]2+ cation with the general formula (NMe4) aK b[(Mo2O2S2) c(TeO4) d(C4O4) e(OH) f] where a, b, c, d, e, f={1,7,14,2,4,10}= 1, {Mo28Te2}; {2,26,36,12,10,48}= 2, {Mo72Te12}; {0,11,15,3,3,21}= 3, {Mo30Te3}; {2,6,12,2,4,16}= 4, {Mo24Te2}. The incorporation of tellurite anions allowed the fine tuning of the templating and bridging of the available building blocks, leading to new topologies of increased complexity. The structural diversity of this family of compounds ranges from the highly symmetrical cross-shaped {Mo24Te2} to the stacked ring structure of {Mo72Te12}, which is the largest tellurium-containing POTM cluster reported so far. Also a detailed experimental analysis revealed that the pH isolation window extends from acidic to basic values. ESI-MS analyses not only confirmed the stability of this family in solution but also revealed the stability of the observed virtual building blocks. [ABSTRACT FROM AUTHOR]

The preparation and characterization of a new family of four polyoxothiometalate (POTM) clusters are reported, with varying size and complexity, based upon the dimeric [Mo2O2S2(H2O)6]2+ cation with the general formula (NMe4) aK b[(Mo2O2S2) c(TeO4) d(C4O4) e(OH) f] where a, b, c, d, e, f={1,7,14,2,4,10}= 1, {Mo28Te2}; {2,26,36,12,10,48}= 2, {Mo72Te12}; {0,11,15,3,3,21}= 3, {Mo30Te3}; {2,6,12,2,4,16}= 4, {Mo24Te2}. The incorporation of tellurite anions allowed the fine tuning of the templating and bridging of the available building blocks, leading to new topologies of increased complexity. The structural diversity of this family of compounds ranges from the highly symmetrical cross-shaped {Mo24Te2} to the stacked ring structure of {Mo72Te12}, which is the largest tellurium-containing POTM cluster reported so far. Also a detailed experimental analysis revealed that the pH isolation window extends from acidic to basic values. ESI-MS analyses not only confirmed the stability of this family in solution but also revealed the stability of the observed virtual building blocks. [ABSTRACT FROM AUTHOR]

Intercalation catalysts, owing to their modular and accessible gallery and unique interlamellar chemical environment, have shown wide application in various catalytic reactions. However, the poor mass transfer between the active components of the intercalated catalysts and organic substrates is one of the challenges that limit their further application. Herein, we have developed a novel heterogeneous catalyst by intercalating the polyoxometalate (POM) of Na9LaW10O36⋅32 H2O (LaW10) into layered double hydroxides (LDHs), which have been covalently modified with ionic liquids (ILs). The intercalation catalyst demonstrates high activity and selectivity for the epoxidation of various allylic alcohols in the presence of H2O2. For example, trans-2-hexen-1-ol undergoes up to 96 % conversion and 99 % epoxide selectivity at 25 °C in 2.5 h. To the best of our knowledge, the Mg3Al−ILs−C8−LaW10 composite material constitutes one of the most efficient heterogeneous catalysts for the epoxidation of allylic alcohols (including the hydrophobic allylic alcohols with long alkyl chains) reported so far. [ABSTRACT FROM AUTHOR]

Intercalation catalysts, owing to their modular and accessible gallery and unique interlamellar chemical environment, have shown a wide range of applications in various catalytic reactions. However, the poor mass‐transfer between the active components of the intercalated catalysts and organic substrates is one of the challenges that limit their further applications. A novel heterogeneous catalyst was fabricated by intercalating the active polyoxometalate (POM) into the ionic‐liquid‐modified layered double hydroxides (LDHs). This novel intercalation catalyst demonstrates high activity and selectivity for epoxidation of various allylic alcohols in the presence of H2O2 under mild conditions. More information can be found in the Full Paper by Y.‐F. Song et al. on page 1069 ff. [ABSTRACT FROM AUTHOR]