Abstract A study concerning the effect of using a fluorinated aromatic solvent as medium for olefin metathesis reactions catalysed by ruthenium complexes bearing N‐heterocyclic carbene ligands is presented. The use hydrocarbons (FAH) solvents standard commercially available pre‐catalysts allows substantially higher yields desired products to be obtained, especially in case demanding polyfunctional molecules, including natural and biologically active compounds. Interactions between FAH...

The preparation and X-ray structure characterization of new olefin metathesis initiators containing sulfone- sulfonamide-substituted benzylidene ligands are described. We observed that these catalysts exhibit Ru···O(SO)R interactions, forming six-membered chelates. Tuning the electronic steric factors part as well selecting proper NHC can have a direct impact on catalyst activity stability, leading to promising catalysts.

Unprecedented amido derivatives of the first-, second-, and third-generation Grubbs ruthenium catalysts were prepared, characterized, tested in ring-closing metathesis (RCM) model dienes. In ruthenium–amide (formally: 2-ruthenaindole) form, these complexes exhibit nearly no activity RCM. However, a dramatic increase was observed upon situ activation with an ethereal solution HCl (see figure). Detailed facts importance to specialist readers are published as "Supporting Information". Such...

In this contributione density functional theory was used to gain insight into the conformational flexibility of acyclic diaminocarbenes and their corresponding Hoveyda- Grubbs-class ruthenium complexes. Remarkably, all known crystal structures carbenes Hoveyda-type Ru complexes show only one specific conformer. We demonstrate that rotation about C–N bonds in free is thermally accessible (∼20 kcal/mol), but relatively restricted upon coordination, primarily due steric constraints. As a...

A novel series of sulfoxide complexes with an additional 3-bromopyridine ligand was obtained and characterized. The initiators were compared in ring-closing metathesis reactions, showing a faster initiation six-coordinated analogues. theoretical study performed utilizing the density functional theory to explain observed reactivity differences. results confirmed different mechanism for both compound classes, multistep sequence pyridine-containing ones, explaining differences catalytic behavior.

An investigation of aza analogues the popular Hoveyda–Grubbs catalyst containing a secondary amine ligand is presented, proving crucial impact steric as well electronic factors on catalyst's stability and performance. The issue latency in reactivity profile studied catalysts examined, followed by structural application studies.

We used the density functional theory to evaluate suitability of nitrenium ions and trivalent boron ligands as analogues N-heterocyclic carbenes in ruthenium-based metathesis catalysts. demonstrate that these induce only minor structural changes Hoveyda-Grubbs-like precatalysts, but have major impact on precatalyst initiation. Nitrenium ion-modified precatalysts are characterized by a weak Ru-N bond resulting relatively strong Ru-O large free energy barriers for initiation, making them good...

Abstract Catalytic and crystallographic studies of Hoveyda–Grubbs type pre‐catalysts M51 TM M52 were performed. These two new instruments in the olefin metathesis catalyst toolbox shown to be active at ambient temperature low loading, leading clean formation ring‐closing, ring‐closing enyne cross products.

Two ruthenium olefin metathesis initiators featuring electronically modified quinoline-based chelating carbene ligands are introduced. Their reactivity in RCM and ROMP reactions was tested the results were compared to those obtained with parent unsubstituted compound. The studied complexes very stable at high temperatures up 140 °C. placement of an electron-withdrawing functionality translates into enhanced activity RCM. While precatalysts, which exist predominantly trans -dichloro...

This paper presents experimental charge-density studies of cytosinium chloride, adeninium chloride hemihydrate and guaninium dichloride crystals based on ultra-high-resolution X-ray diffraction data extensive theoretical calculations. The results confirm that the cohesive energies studied systems are dominated by contributions from intermolecular electrostatic interactions, as expected for ionic crystals. Electrostatic interaction ( E es ) usually constitute 95% total energy. in this study...

Abstract With the aim of developing new IR‐detectable metal–carbonyl tracers for amino function, we have synthesized W(CO) 5 complexes 4‐oxo‐4‐(2,5‐dimethylazaferrocen‐1′‐yl)butanoic acid ( 2 ) and 5‐oxo‐5‐(2,5‐dimethylazaferrocen‐1′‐yl)pentanoic 3 by AlCl ‐catalyzed Friedel–Crafts reaction –2,5‐dimethylazaferrocene 1 with succinic or glutaric anhydride. Complexes are thermally stable display sharp, intense absorption bands tungsten‐coordinated CO ligands at ca. 1923 cm –1 . In crystalline...

A corrected and improved structure of the polymorph II 2C3H8NO3 (+)·C2O4 (2-)·2H2O, based on single-crystal data, is presented. The refined with anisotropic displacement parameters for all non-H atoms H are located. Due to charged moieties, classified as a mol-ecular salt. Inter-molecular O-H⋯O(-), O-H⋯O N(+)-H⋯O(-)hydrogen bonds link components structure. l-serinium cations oxalate anions form network channels in [100] direction, filled water molecules crystallization. dihedral angle...

Journal Article Challenging Modernity, by ROBERT N. BELLAH, edited RICHARD MADSEN, WILLIAM M. SULLIVAN, ANN SWIDLER, and STEVEN TIPTON Get access TIPTON. New York: Columbia University Press, 2024, 361 pp., $32. Anna Pazio of Warsaw, Poland [email protected] https://orcid.org/0009-0005-0133-4357 Search for other works this author on: Oxford Academic Google Scholar Sociology Religion, srae039, https://doi.org/10.1093/socrel/srae039 Published: 26 December 2024

ADVERTISEMENT RETURN TO ISSUEPREVAddition/CorrectionORIGINAL ARTICLEThis notice is a correctionCorrection to Thermal Switchability of N-Chelating Hoveyda-type Catalyst Containing Secondary Amine LigandKarolina Żukowska, Anna Szadkowska*, Aleksandra E. Pazio, Krzysztof Woźniak, and Karol Grela*Cite this: Organometallics 2012, 31, 9, 3814Publication Date (Web):May 3, 2012Publication History Published online3 May 2012Published inissue 14...

The following paper presents experimental charge density studies of cytosinium chloride, adeninium chloride hemihydrate, and guanine dichloride crystals based on ultra-high resolution X-ray diffraction data extensive theoretical calculations. Results confirm that the cohesive energies studied systems are dominated by contributions from intermolecular electrostatic interactions, as expected for ionic crystals. Electrostatic interactions (Ees) usually constitute 95% total interaction energies....

Sessions C760resulting in ferroelectricity BiFeO 3 is driven by a lone pair of the Bi 3+ cation [2,3].Due to similarity between electronic structures and Pb 2+ , substitution for provides potential way modify electric magnetic properties mixed lead-bismuth ferrites.Anion-deficient perovskites (Pb,Bi) 1-x Fe 1+x O 3-y were prepared as single phases compositional range from 0.857 0.094 1.049 2.572 0.409 0.567 1.025 2.796 .Variation anion content compounds carried out through long-range-ordered...

Radical cation salts and charge transfer complexes based on tetrathiafulvalene (TTF) their derivatives constitute a wide class of organic materials with transport properties ranging from insulating to superconducting.The iron group metal bis (1,2-dicarbollide) [3,3'-M(1,2-C 2 B 9 H 11 ) ] -(M = Fe, Co, Ni) have been proposed as counterions for synthesis new radical cation-based molecular materials.Substitution hydrogen atoms in these various groups opens practically unlimited perspectives...