Role of Lattice Oxygen of Metal Oxides in the Dehydrogenation of Ethylbenzene under a Carbon Dioxide Atmosphere†

2010 ◽  
Vol 114 (11) ◽  
pp. 3845-3854 ◽  
Author(s):  
Kazuhiro Saito ◽  
Kazumi Okuda ◽  
Na-oki Ikenaga ◽  
Takanori Miyake ◽  
Toshimitsu Suzuki
Keyword(s):  
Carbon Dioxide ◽  
Metal Oxides ◽  
Lattice Oxygen ◽  
Carbon Dioxide Atmosphere ◽  
Dehydrogenation Of Ethylbenzene

scholarly journals A CO2-Mediated Conjugate Cyanide Addition to Chalcones

Catalysts ◽  
2020 ◽  
Vol 10 (12) ◽  
pp. 1481
Author(s):  
Simon Dotzauer ◽  
Gul Barg Hadaf ◽  
Fadhil S. Kamounah ◽  
Anders Kadziola ◽  
Ji-Woong Lee
Keyword(s):  
Carbon Dioxide ◽  
Inert Atmosphere ◽  
Side Reactions ◽  
Metal Cyanide ◽  
Carbon Dioxide Atmosphere ◽  
Nucleophilic Reagents ◽  
Dimerization Reaction ◽  
Functional Group Transformation ◽  
Stable Molecule

Carbon dioxide is an intrinsically stable molecule; however, it can readily react with various nucleophilic reagents. In the presence of a cyanide source, CO2 was proven to be useful to promote addition reactions. Here we report the use of CO2 to facilitate 1,4-conjugate cyanide addition reaction to chalcones to generate organonitriles. Nitriles are key component in organic synthesis due to their utility in numerous functional group transformation, however, conjugation addition of cyanide has been a challenge in this substrate class due to side reactions. To mitigate this, we employed simple ammonium and metal cyanide sources as nucleophiles under carbon dioxide atmosphere where high selectivity toward the desired product was obtained. The presented reaction is not feasible under inert atmosphere, which highlights the important role of CO2, as a Lewis and Brøndsted acidic catalyst. Further derivatization of organonitriles compounds were performed to showcase the utility of the reaction, while an unprecedented dimerization reaction was identified and characterized, affording a cyclopentanone scaffold.

Unraveling the Role of Zinc on Bimetallic Fe5C2–ZnO Catalysts for Highly Selective Carbon Dioxide Hydrogenation to High Carbon α-Olefins

ACS Catalysis ◽  
2021 ◽  
Vol 11 (4) ◽  
pp. 2121-2133
Author(s):  
Chao Zhang ◽  
Chenxi Cao ◽  
Yulong Zhang ◽  
Xianglin Liu ◽  
Jing Xu ◽  
...  
Keyword(s):  
Carbon Dioxide ◽  
High Carbon ◽  
Carbon Dioxide Hydrogenation

Prebiotic studies on the interaction of zirconia nanoparticles and ribose nucleotides and their role in chemical evolution

2021 ◽  
Vol 20 (2) ◽  
pp. 142-149
Author(s):  
Avnish Kumar Arora ◽  
Pankaj Kumar
Keyword(s):  
Electron Microscopy ◽  
Metal Oxide ◽  
Metal Oxides ◽  
Chemical Evolution ◽  
Ribonucleic Acid ◽  
Zirconium Oxide ◽  
Origins Of Life ◽  
Neutral Ph ◽  
Interaction Studies

AbstractStudies on the interaction of biomolecules with inorganic compounds, mainly mineral surfaces, are of great concern in identifying their role in chemical evolution and origins of life. Metal oxides are the major constituents of earth and earth-like planets. Hence, studies on the interaction of biomolecules with these minerals are the point of concern for the study of the emergence of life on different planets. Zirconium oxide is one of the metal oxides present in earth's crust as it is a part of several types of rocks found in sandy areas such as beaches and riverbeds, e.g. pebbles of baddeleyite. Different metal oxides have been studied for their role in chemical evolution but no studies have been reported about the role of zirconium oxide in chemical evolution and origins of life. Therefore, studies were carried out on the interaction of ribonucleic acid constituents, 5′-CMP (cytidine monophosphate), 5′-UMP (uridine monophosphate), 5′-GMP (guanosine monophosphate) and 5′-AMP (adenosine monophosphate), with zirconium oxide. Synthesized zirconium oxide particles were characterized by using vibrating sample magnetometer, X-Ray Diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy. Zirconia particles were in the nanometre range, from 14 to 27 nm. The interaction of zirconium oxide with ribonucleic acid constituents was performed in the concentration range of 5 × 10−5–300 × 10−5 M. Interaction studies were carried out in three mediums; acidic (pH 4.0), neutral (pH 7.0) and basic (pH 9.0). At neutral pH, maximum interaction was observed. The interaction of zirconium oxide with 5′-UMP was 49.45% and with 5′-CMP 67.98%, while with others it was in between. Interaction studies were Langmurian in nature. Xm and KL values were calculated. Infrared spectral studies of ribonucleotides, metal oxide and ribonucleotide–metal oxide adducts were carried out to find out the interactive sites. It was observed that the nitrogen base and phosphate moiety of ribonucleotides interact with the positive charge surface of metal oxide. SEM was also carried out to study the adsorption. The results of the present study favour the important role of zirconium oxide in concentrating the organic molecules from their dilute aqueous solutions in primeval seas.

Sign in / Sign up

Export Citation Format

Share Document