Reusable Copper Catechol‐based Porous Polymers for the Highly Efficient Heterogeneous Catalytic Oxidation of Secondary Alcohols

New catechol-based porous polymers were synthesized and used as platforms for the heterogenization of molecular Cu complexes. The resulting Cu@CatMP-1 materials proved to be highly stable and performing catalysts for the oxidation of secondary alcohols with turnover numbers up to 6000, about 1 to 2 orders of magnitude higher than the current relevant state of the art, using catalyst loadings as low as 25 ppm of Cu. The solid catalyst proved to be recyclable for over 10 runs without detectable metal leaching and has been scaled to the gram scale. The coordination of Cu to catechol within the polymer has been evidenced by X-ray absorption spectroscopy

Selectieve distributie en uitputting van het merkenrecht. Uniciteit op de helling?

status: publishe

Considerations on the performance of immunocastrated male pigs

With the ongoing social pressure on surgical castration of pigs, an increase in the population of pigs that are either not castrated or immunocastrated (IC) can be expected. In both cases, their nutrient requirements and performance will differ from surgically castrated pigs and will require changes in their management. Immunocastration is performed by giving two injections of a modified gonadotrophin-releasing hormone component along with an adjuvant, at least 4 weeks apart. This paper describes the reported differences in growth performance and carcass quality of IC male pigs in comparison with boars (BO) and barrows (BA). Theoretically, IC pigs remain physiologically boar until the second vaccination and therefore, growth may be comparable with BO until this second vaccination. From then on, IC male pigs consume more feed than BO and grow faster when fed ad libitum. IC showed a faster growth and better feed conversion ratio than BA. When fed restrictedly, BO grow faster and more efficiently than BA and IC. IC have a lower carcass yield than BA and BO, whereas meat percentage is intermediate

Copper–cobalt double metal cyanides as green catalysts for phosphoramidate synthesis

Abstract Phosphoramidates are common and widespread backbones of a great variety of fine chemicals, pharmaceuticals, additives and natural products. Conventional approaches to their synthesis make use of toxic chlorinated reagents and intermediates, which are sought to be avoided at an industrial scale. Here we report the coupling of phosphites and amines promoted by a Cu3[Co(CN)6]2-based double metal cyanide heterogeneous catalyst using I2 as additive for the synthesis of phosphoramidates. This strategy successfully provides an efficient, environmentally friendly alternative to the synthesis of these valuable compounds in high yields and it is, to the best of our knowledge, the first heterogeneous approach to this protocol. While the detailed study of the catalyst structure and of the metal centers by PXRD, FTIR, EXAFS and XANES revealed changes in their coordination environment, the catalyst maintained its high activity for at least 5 consecutive iterations of the reaction. Preliminary mechanism studies suggest that the reaction proceeds by a continuous change in the oxidation state of the Cu metal, induced by a O2/I− redox cycle

Olefins from Biobased Sugar Alcohols via Selective, Ru-Mediated Reaction in Catalytic Phosphonium Ionic Liquids

status: publishe

In Situ X-ray Absorption Spectroscopy Cells for High Pressure Homogeneous Catalysis

We have designed, built, and tested two cells for in situ and, potentially, operando X-ray absorption spectroscopy experiments in transmission and fluorescence modes. The cells were developed for high-pressure and high-temperature conditions to study the catalytic processes under relevant industrial conditions. Operation of the cells was tested for Ru and Rh-based homogeneous and heterogeneous catalytic systems. Using synchrotron-based in situ X-ray absorption spectroscopy we tracked the evolution of active metal species during catalytic reactions. Our setup proved that it was capable to investigate liquid-state homogeneous and heterogenous systems under elevated temperatures, high pressures of reactive gasses, and in the presence of corrosive reagents