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Herein, the preparation of SrTiO3-based catalysts (i.e., NiO/support, Au-support and Au–NiO/support, where the supports were SrTiO3and SrTiO3–SrCO3) for photocatalytic CO2reduction considering strategic design principles is presented. The samples were comprehensively analyzed viacomplementary methods, such as SEM-EDX, XRD, nitrogen sorption, XPS and UV-vis (DRS), in situEPR and in situDRIFTS. The CO2photoreduction activity of the samples was assessed in a high-purity gas-phase photoreactor under batch conditions. The investigations highlighted that the reaction pathway (i.e., selective H2and C2H6production vs.CH4) can be influenced by the modification of the electronic properties (i.e., Fermi level alignment), the interaction between Au NPs and oxygen vacancies (i.e., in situEPR) and the enhanced charge separation in the presence of SrCO3. The participation of the structural carbonates in the reaction in association with the functionality of the components is discussed.

Structural and dynamic properties of BiPhePhos modified rhodium complexes under hydroformylation conditions have been investigated in detail by using high-pressure (HP) in situtransmission IR- and NMR-spectroscopy. An experiment design approach which combines component/reagent perturbations, in situ-FTIR measurements and chemometric peak group analysis (PGA) led to the identification of most relevant components. The ligand coordination in the structures of the hydrido and acyl 18-VE resting state complexes has been elucidated. The hydrido complex of the type e,e-[HRh(CO)2(P∩P)] represents the dominant resting state after catalyst preformation and during the n-regioselective hydroformylation. Dimer formation only takes place to a minor extent under severe reaction conditions under hydrogen depletion. Mono- and dinuclear hydrido monocarbonyl complexes are formed at higher ligand-to-metal ratios and low partial pressures of carbon monoxide. Both stereoisomeric forms of the bisphosphite modified acyl complexes e,a-[RC(O)Rh(CO)2(P∩P)] and e,e-[RC(O)Rh(CO)2(P∩P)] are generated as an equilibrium mixture.

Green Friedel–Crafts acylation reactions belong to the most desired transformations in organic chemistry. The resulting ketones constitute important intermediates, building blocks, and functional molecules in organic synthesis as well as for the chemical industry. Over the past 60 years, advances in this topic have focused on how to make this reaction more economically and environmentally friendly by using green acylating conditions, such as stoichiometric acylations and catalytic homogeneous and heterogeneous acylations. However, currently well-established methodologies for their synthesis either produce significant amounts of waste or proceed under harsh conditions, limiting applications. Here, we present a new protocol for the straightforward and selective introduction of acyl groups into (hetero)arenes without directing groups by using available olefins with inexpensive CO. In the presence of commercial palladium catalysts, inter- and intramolecular carbonylative C–H functionalizations take place with good regio- and chemoselectivity. Compared to classical Friedel–Crafts chemistry, this novel methodology proceeds under mild reaction conditions. The general applicability of this methodology is demonstrated by the direct carbonylation of industrial feedstocks (ethylene and diisobutene) as well as of natural products (eugenol and safrole). Furthermore, synthetic applications to drug molecules are showcased.

A tube Ge60H60isomer in D5dsymmetry with fused five-membered rings located at the ends of the tube is more stable than the fullerene-like Ihcage isomer at the B3LYP/cc-pVDZ level of theory. Introducing endo Ge−H bonds increases the stability of both cage and tube isomers. The most stable tube isomer can admit six endo Ge−H bonds. The cage isomer can admit 10−12 endo Ge−H bonds (H10@Ge60H50and H12@Ge60H48), and they also represent the most stable Ge60H60isomers. The stability order and structural patterns of Ge60H60are the same as those found for the corresponding Si60H60isomers. Moreover, it is found that the 6-31G(d,p) basis set fails to predict the relative energies of the Ge60H60isomers and the Ge6H6isomers.

Non-metal-catalyzed heterodehydrocoupling of primary and secondary phosphines (R1R2PH, R2= H or R1) with hydrosilanes (R3R4R5SiH, R4, R5= H or R3) to produce synthetically useful silylphosphines (R1R2P–SiR3R4R5) has been achieved using B(C6F5)3as the catalyst (10 mol %, 100 °C). Kinetic studies demonstrated that the reaction is first-order in hydrosilane and B(C6F5)3but zero-order in phosphine. Control experiments, DFT calculations, and DOSY NMR studies suggest that a R1R2HP·B(C6F5)3adduct is initially formed and undergoes partial dissociation to form an “encounter complex”. The latter mediates frustrated Lewis pair type Si–H bond activation of the silane substrates. We also found that B(C6F5)3catalyzes the homodehydrocoupling of primary phosphines to form cyclic phosphine rings and the first example of a non-metal-catalyzed hydrosilylation of P–P bonds to produce silylphosphines (R1R2P–SiR3R4R5). Moreover, the introduction of PhCN to the reactions involving secondary phosphines with hydrosilanes allowed the heterodehydrocoupling reaction to proceed efficiently under much milder conditions (1.0 mol % B(C6F5)3at 25 °C). Mechanistic studies, as well as DFT calculations, revealed that PhCN plays a key mechanistic role in facilitating the dehydrocoupling reactions rather than simply functioning as H2-acceptor.