Search results for "Main group element"
showing 10 items of 12 documents
A versatile metathesis reaction for the formation of labile bonds between group 13 and group 15 atoms.
2003
Zirconocene [Cp2Zr] synthon and benzynezirconocene complexes as tools in main group element chemistry
1998
Abstract Interactions between zirconocene or benzyne zirconocene and unsaturated species incorporating main group elements lead to a variety of new metallaheterocycles. Efficient new methodologies of regiospecific syntheses of mono-, bi-, or tricyclic systems incorporating phosphorus, nitrogen, selenium, antimony, germanium or tin are reported.
The Synthesis of Quinoline-based Tin Complexes with Pendant Schiff Bases
2019
Molecular structures of Se(SCH3)2 and Te(SCH3)2 using gas-phase electron diffraction and ab initio and DFT geometry optimisations
2005
The molecular structures of Se(SCH3)2 and Te(SCH3)2 were investigated using gas-phase electron diffraction (GED) and ab initio and DFT geometry optimisations. While parameters involving H atoms were refined using flexible restraints according to the SARACEN method, parameters that depended only on heavy atoms could be refined without restraints. The GED-determined geometric parameters (rh1) are: rSe-S 219.1(1), rS-C 183.2(1), rC-H 109.6(4) pm; S-Se-S 102.9(3), Se-S-C 100.6(2), S-C-H (mean) 107.4(5), S-Se-S-C 87.9(20), Se-S-C-H 178.8(19)° for Se(SCH3)2, and rTe-S 238.1(2), rS-C 184.1(3), rC-H 110.0(6) pm; S-Te-S 98.9(6), Te-S-C 99.7(4), S-C-H (mean) 109.2(9), S-Te-S-C 73.0(48), Te-S-C-H 180.…
Substitution Effects in Double Perovskites: How the Crystal Structure Influences the Electronic Properties
2013
We systematically studied substituted Sr2FeReO6 with respect to experimental characterization and theoretical band structure calculations. In the framework of the tight-binding approach, hole- or electron-doping of Sr2MM’O6 were performed at the M or M’ positions either by transition or main group metals. Hole-doping, rather than electron-doping, has a favorable effect to improve the half-metallicity (Curie temperature and saturation magnetization) of the parent compound. When M is substituted by another metal, the original M’ metal will serve as a redox buffer (and vice versa). Substituting M by another metal with a size similar to that of the metal at M’ position causes disorder, which ha…
Bimetallic Complexes from Amphoteric Group 13/15 Ligands: Syntheses and X-ray Crystal Structures
2002
Bimetallic, pentel-bridged complexes of the type [(dmap)Me 2 -M-E(SiMe 3 ) 2 -M'(CO) n ] (M = Al, Ga; E=P, As, Sb; M'=Cr, Fe, Ni; DMAP= 4-(dimethylamino)pyridine) are formed by reactions of DMAP-coordinated monomeric Group 13/15 compounds [(dmap)Me 2 M-E(SiMe 3 ) 2 ] with the transition metal complexes [(Me 3 N)Cr-(CO) 5 ], [Fe 3 (CO) 1 2 ], and [Ni(CO) 4 ]. For the first time, this reaction offers a general pathway to compounds containing a Group 13 metal and a transition metal bridged by a pentel atom. Complexes prepared in this way were characterized by IR and multinuclear NMR spectroscopy and by single-crystal X-ray structure analysis. Their electronic and structural properties are disc…
Dinitrogen complexation with main group radicals
2011
In this report we present data from hyperfine sublevel correlation spectroscopy (HYSCORE), an electron paramagnetic resonance (EPR) spectroscopic technique, that reveals weak but distinct interactions between several main group element radicals and physically dissolved dinitrogen in solution. These interactions are the basis for a well-defined coordination of N2 to the paramagnetic centers. The complexes formed are primarily of the van der Waals-type but also feature a non-negligible orbital overlap between dinitrogen and the radicals' SOMO. Our spectroscopic findings are strongly supported by experiments with isotope-labeled 15N2, spectral simulations and quantum chemical and density funct…
New Insights into the Chemistry of Imidodiphosphinates from Investigations of Tellurium-Centered Systems
2010
Dichalcogenido-imidodiphosphinates, [N(PR(2)E)(2)](-) (R = alkyl, aryl), are chelating ligands that readily form cyclic complexes with main group metals, transition metals, lanthanides, and actinides. Since their discovery in the early 1960s, researchers have studied the structural chemistry of the resulting metal complexes (where E = O, S, Se) extensively and identified a variety of potential applications, including as NMR shift reagents, luminescent complexes in photonic devices, or single-source precursors for metal sulfides or selenides. In 2002, a suitable synthesis of the tellurium analogs [N(PR(2)Te)(2)](-) was developed. In this Account, we describe comprehensive investigations of t…
Intramolecular coupling of acetylenic groups of bis(alkynyl)phosphanes and silanes mediated by benzynezirconocene: a route to new mono- and tricyclic…
2004
Benzo-zirconacyclohexadiene-phospha or silacyclobutene fused ring systems are easily prepared via a benzynezirconocene intermediate by means of thermolysis of Cp 2 ZrPh 2 in the presence of bis(alkynyl)phosphanes or silanes. These polyunsaturated systems are the source of a variety of new mono- or tricyclic heterocycles incorporating either one or two heteroatoms.
Addition of Ethylene or Hydrogen to a Main-Group Metal Cluster under Mild Conditions
2015
Reaction of the tin cluster Sn8(Arinline image)4 (Arinline image=C6H2-2,6-(C6H3-2,4,6-Me3)2) with excess ethylene or dihydrogen at 25 °C/1 atmosphere yielded two new clusters that incorporated ethylene or hydrogen. The reaction with ethylene yielded Sn4(Arinline image)4(C2H2)5 that contained five ethylene moieties bridging four aryl substituted tin atoms and one tin–tin bond. Reaction with H2 produced a cyclic tin species of formula (Sn(H)Arinline image)4, which could also be synthesized by the reaction of {(Arinline image)Sn(μ-Cl)}2 with DIBAL-H. These reactions represent the first instances of direct reactions of isolable main-group clusters with ethylene or hydrogen under mild conditions…