Two new one-component aluminium-based catalysts for the reaction between epoxides and carbon dioxide have been prepared. The catalysts are composed of aluminium-salen chloride complexes with trialkylammonium groups directly attached to the aromatic rings of the salen ligand. With terminal epoxides, the catalysts induced the formation of cyclic carbonates under mild reaction conditions (25-35 °C...

Selectivity in the catalytic functionalization of complex molecules is a major challenge in chemical synthesis. The problem is magnified when there are several possible stereochemical outcomes and when similar functional groups occur repeatedly within the same molecule. Selective polyene oxidation provides an archetypical example of this challenge. Historically, enzymatic catalysis has provided...

Vanillin is one of the most commonly used natural products, which can also be produced from lignin-derived feedstocks. The chemical synthesis of vanillin is well-established in large-scale production from petrochemical-based starting materials. To overcome this problem, lignin-derived monomers (such as eugenol, isoeugenol, ferulic acid etc.) have been effectively used in the past few years. How...

In this review, we provide an overview of recent progress in nanocarbons with different dimensions as noble-metal-free co-catalysts for photocatalysts. We put emphasis on the interface engineering between nanocarbon co-catalysts and various semiconductor photocatalysts and the novel properties generating of nanocarbon co-catalysts, also including the synthesis and application of nanocarbon-base...

Ten novel hydrogen-bonding catalysts based on open-chain P(V)-amides of BINOL and chinchona alkaloids as well as three catalysts based on rigid cis-P(V)-cyclodiphosphazane amides of N (1),N (1)-dimethylcyclohexane-1,2-diamine have been developed. Employed in the asymmetric Michael addition of 2-hydroxynaphthoquinone to β-nitrostyrene, the open-chain 9-epi-aminochinchona-based phosphorus amides ...

in this research na-y was synthesized by hydrothermal method and used as support for preparation of sn/pt/na-y catalysts using two different tin precursors, bu3sn(cl) and sncl2.2h2o, by sequential impregnation, in which the pt  was deposited first and in the next step sn was deposited. the catalysts were characterized by h2 chemisorption, transmission electron microscopy (tem), scanning electro...

The current study examined the effect of metal oxide catalysts on the sorption and photocatalytic efficiencies for the removal of ciprofloxacin and ofloxacin in water. ZnO and TiO2 catalysts are prepared using a suitable method based on the sol-gel process, which have a great change in structural and textural properties. The structure and surface area of the synthesized catalysts wer...

In this review, the most recent advances (2014-2016) on the synthesis of new polymer-supported catalysts are reported, focusing the attention on the synthetic strategies developed for their preparation. The polymer-supported catalysts examined will be organic-based polymers and organic-inorganic hybrids and will include, among others, polystyrenes, poly-ionic liquids, chiral ionic polymers, den...

reactants, reagents, and catalysts. A wide variety of performances of transition-metal catalysts are considerably dependent on the electronic states belonging to d-orbital electrons having dif ferent oxidative or spin states designed by coordinated ligands. To explore high-performance catalysts, analytical investigation based on electronic states is necessary, and theoretical calculations are i...

BACKGROUND Transesterification catalyzed by solid base catalyst is a brilliant technology for the noble process featuring the fast reaction under mild reacting condition in biodiesel production. Heterogeneous base catalysts are generally more reactive than solid acid catalysts which require extreme operating condition for high conversion and biodiesel yield. In the present study, synthesis of b...