Treatment of ceric ammonium nitrate (CAN) with varying amounts of sodium neopentoxide led to the isolation of crystalline cerium(IV) complexes [Ce(OCHtBu)(NO)(HOCHtBu)], [Ce(OCHtBu)(NO)-(NCCH)], [Ce(OCHtBu)(NO)], and [Ce(OCHtBu)Na-(THF)] featuring Ce/(OR) ratios of 1:2, 1:3, 1:3.5, and 1:4.5, respectively. The complexes are light-sensitive and prone to ligand redistribution as evidenced by multicomponent NMR spectra as well as the formation of [{Ce(OCHtBu)}(THF)] and the mixed-valent complex [Ce(OCHtBu)(NO)]. The CAN protocol also gave access to the isopropoxide derivative [Ce(OiPr)(NO)(THF)]. The reaction of [EtN][CeCl] (CAC, ceric organoammonium chloride) with different equivalents of Na(OCHtBu) was also impaired by ligand reorganization and ate complexation as detected for the tetravalent cerium complex [Ce(OCHtBu)Cl][EtN]. Protonolysis of [Ce{N(SiHMe)}] with 4 equiv of HOCHtBu afforded donor-free homoleptic [Ce(OCHtBu)] in quantitative yield. All complexes were characterized by NMR, DRIFT, and UV-vis spectroscopy, as well as paramagnetic susceptibility measurements, X-ray structure analysis, and elemental analysis.

The Meerwein–Ponndorf–Verley (MPV) reduction is a reaction that offers a mild reduction of aldehydes and ketones to the corresponding alcohols. Although described as a catalytic reaction, its real-life applicability suffers from the necessity of using the standard catalyst [Al­(OiPr)3] in stoichiometric amounts or even in excess. Rare-earth-metal-based catalysts are capable of performing in these reactions in a truly catalytic fashion. The ceric alkoxide [Ce­(OiPr)4]3 has been synthesized via silylamine elimination from Ce­[N­(SiHMe2)2]4 with isopropyl alcohol, its trimetallic solid-state structure has been determined by X-ray diffraction, and its performance in the MPV reduction of 4-tBu-cyclohexanone has been examined and compared to that of cerous [Ce­(OCH2 tBu)3]4. Spherical mesoporous silica nanoparticles with an MCM-41-type honeycomb pore symmetry, termed MSN-MCM-41 (particle size, ca. 250 nm diameter; pore size, 2.6 nm diameter), are employed for grafting the molecular precursors Ce­[N­(SiHMe2)2]4, [Ce­(OiPr)4]3, Ce­[N­(SiMe3)2]3, and La­[N­(SiMe3)2]3 according to the methods of surface organometallic chemistry (SOMC). The MPV reductions carried out with the homogeneous and heterogeneous catalysts reveal (a) a better performance of Ce­(III) in comparison to Ce­(IV), (b) better performance of La­[N­(SiMe3)2]3@MSN-MCM-41 in comparison to Ce­[N­(SiMe3)2]3@MSN-MCM-41 (high sensitivity of Ce­(III)-grafted materials), and (c) reusability of the grafted catalyst systems. All hybrid materials were characterized by PXRD, N2 physisorption, and 1H/13C/29Si MAS NMR and FTIR spectroscopies as well as elemental analysis.

Despite immense research efforts in the field of noble metal‐loaded mesoporous silica nanoparticles, the rational design and fabrication of nanosystems with high catalytic efficiency are still a major challenge. The main obstacles are faced when adjusting the size of the implemented metal nanoparticles and when modulating the porosity of nanoreactor arrays. Herein, a series of hierarchically structured core‐shell nanoparticles was synthesized, consisting of a mesoporous siliceous shell and either a thiol‐functionalized mesoporous organosilica core (SH‐MON‐n@MS; n = 1, 2, 3, 4) or an amino‐functionalized variant (NH2‐MON@MS). The distinct core/shell composition enables a selective loading of Au nanoparticles into the core domain affording the hierarchically structured materials Au/SH‐MON‐n@MS (n = 1, 2, 3, 4) and Au/NH2‐MON@MS. The larger shell mesopores facilitate easy access and diffusion of reactants and products, while the inner organosilica pores provide a hydrophobic microenvironment. Due to the superior structural properties, the materials Au/SH‐MON‐n@MS (n = 1, 2, 3, 4) exhibit excellent catalytic performance in the reduction of 4‐nitrophenol to 4‐aminophenol. However, the aerobic oxidation of benzyl alcohol to benzaldehyde is only promoted by Au/SH‐MON‐2@MS, revealing that Au loading and the core pores are main factors to govern the catalytic performance, while the air‐flow rate takes also a key role in the catalytic conversion.

Treatment of the ate complex [Ce{N(SiHMe 2 ) 2 } 4 -Li(thf )] with neutral donor molecules (do) gave several solvent(do)-separated ion-pair complexes of the composition [Ce{N(SiHMe 2 ) 2 } 4 ][Li(do) n ] (do = thf, pyridine, tmeda, dme, 12crown-4). Their solid-state structures have been analyzed by Xray diffraction and DRIFTS. Displacement of the [Li(do) n ] entity, resulting in a solvent-separated ion pair with a symmetric envi-[a]

Boron silicate (BS) with a chabazite framework structure was synthesized and ion-exchanged with copper to form Cu-BS which was capable of oxidizing methane to methoxy species.