AI Article Synopsis
Article Abstract
The synthesis of ferrocenylphosphine-borane adducts 1,2-fc(E)(PPh·BH) (E = SnRR', HgX; 1,2-fc = 1,2-ferrocenediyl) that are substituted with organotin or organomercury Lewis acid moieties in ortho-position is presented. Several compounds that feature two ferrocenylphosphine-borane moieties bridged by Sn or Hg are also introduced. The products are fully characterized by multinuclear NMR spectroscopy, high-resolution MALDI-TOF mass spectrometry and elemental analysis. The attachment of the Lewis acid substituent to the same Cp ring of the ferrocene results in planar-chirality and the close proximity between the boron hydride group and the Lewis acid is expected to allow for agostic-type B-HE (E = Sn, Hg) interactions. Structural investigations by X-ray diffraction reveal a short B-HSn contact of 2.755(4) Å for 1,2-fc(SnMeCl)(PPh·BH), which is only the second reported example of such a short agostic-type contact involving a coordinatively saturated tin(iv) center. In contrast, for the tetraorganotin derivatives 1,2-fc(SnMe)(PPh·BH) and [1,2-fc(PPh)](μ-SnMe)[1,2-fc(PPh·BH)], in which the Lewis acidity of the tin atom is weaker than in 1,2-fc(SnMeCl)(PPh·BH), the B-HSn distances are much longer but still within the sum of the van der Waals radii of Sn and H (∑ = 3.27 Å). The chloromercury-substituted ferrocenylphosphine-borane 1,2-fc(HgCl)(PPh·BH) shows a similarly short B-HHg contact of 2.615(5) Å (∑ = 3.15 Å). Inspection of the extended structure of 1,2-fc(HgCl)(PPh·BH) reveals that the Lewis acidic mercury atom is also involved in intermolecular HgCl interactions with a neighboring molecule. An analysis of P and B NMR data reveals a correlation between the chemical shifts and the Lewis acidity of the adjacent organotin/mercury substituent. Structure optimization of 1,2-fc(SnMe)(PPh·BH) and 1,2-fc(SnMeCl)(PPh·BH) by density functional theory (DFT) indicates B-HSn contacts respectively of 3.129 and 2.631 Å that are close to the experimental values. Natural bond orbitals (NBO) and atom in molecules (AIM) analyses reveals a B-H→Sn donor-acceptor interaction energy of 5.46 kcal mol and a B-HSn bond path for the chlorodimethyltin-substituted derivative with a modest electron density ρ(r) of 0.0082 a.u. and a positive Laplacian at the bond critical point.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1039/c6dt04791b | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Frustrated Lewis Pair Meets Polyhedral Oligomeric Silsesquioxane: Water-Tolerant Hybrid Porous Networks for Robust, Efficient, and Recyclable CO Catalysis.
ACS Appl Mater Interfaces
January 2025
State Key Laboratory of Molecular Engineering of Polymers, Fudan University, Shanghai 200433, China.
Frustrated Lewis pair chemistry (FLP) occupy a crucial position in nonmetal-mediated catalysis, especially toward activation of inert gas molecules. Yet, one formidable issue of homogeneous FLP catalysts is their instability on preservation and recycling. Here we contribute a general solution that marries the polyhedral oligomeric silsesquioxane (POSS) with a structurally specific frustrated Lewis acid to fabricate porous polymer networks, which can form water-insensitive heterogeneous FLP catalysts upon employing Lewis base substrates.
View Article and Find Full Text PDFAntimicrobial Effectiveness of Clove Oil in Decontamination of Ready-to-Eat Spinach ( L.).
Foods
January 2025
College of Agriculture, Science and Technology, Delaware State University, 1200 North DuPont Highway, Dover, DE 19901, USA.
Due to an increased demand for natural food additives, clove oil was assessed as a natural alternative to chemical disinfectants in produce washing. This study assessed the antimicrobial activity of 5 and 10% (/) clove oil-amended wash liquid (CO) using a zone of inhibition (ZIB) test and determined the time required to completely inactivate pathogenic bacteria using bacterial death curve analysis. A washing experiment was used to evaluate CO's ability to inhibit bacterial growth on inoculated RTE spinach and in the wash water.
View Article and Find Full Text PDFSLC25A38 is required for mitochondrial pyridoxal 5'-phosphate (PLP) accumulation.
Nat Commun
January 2025
The Picower Institute for Learning and Memory, MIT, Cambridge, MA, USA.
Many essential proteins require pyridoxal 5'-phosphate, the active form of vitamin B6, as a cofactor for their activity. These include enzymes important for amino acid metabolism, one-carbon metabolism, polyamine synthesis, erythropoiesis, and neurotransmitter metabolism. A third of all mammalian pyridoxal 5'-phosphate-dependent enzymes are localized in the mitochondria; however, the molecular machinery involved in the regulation of mitochondrial pyridoxal 5'-phosphate levels in mammals remains unknown.
View Article and Find Full Text PDFComputational Insights into the Mechanism of Lewis Acid-Catalyzed Alkene-Aldehyde Coupling.
Chempluschem
January 2025
University of Vienna, Faculty of Chemistry, Währinger Str. 17, 1090, Vienna, AUSTRIA.
The Lewis acid-catalyzed coupling of alkenes and aldehydes presents a modern, versatile synthetic alternative to classical carbonyl addition chemistry, offering exceptional regio- and stereoselectivity. In this work, we present a comprehensive computational investigation into the reaction mechanism of this transformation. Our findings confirm the occurrence of an enantioselective trans-annular [1,5]-hydride shift step and demonstrate that the enantioselectivity of the reaction arises predominantly from steric clashes between functional groups in the cyclization step.
View Article and Find Full Text PDFStructural investigations of the benzoyl fluoride and the benzoacyl cation of low-melting compounds and reactive intermediates.
Acta Crystallogr C Struct Chem
February 2025
Department Chemie, Ludwig-Maximilians Universität, Butenandtstrasse 5-13 (Haus D), D-81377 München, Germany.
Acyl fluorides and acyl cations represent typical reactive intermediates in organic reactions, such as Friedel-Crafts acylation. However, the comparatively stable phenyl-substituted compounds have not been fully characterized yet, offering a promising backbone. Attempts to isolate the benzoacylium cation have only been carried out starting from the acyl chloride with weaker chloride-based Lewis acids.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!