Computational and experimental approaches to the molecular structure of the HCl adduct of Me3PO.
ABSTRACT: The reaction of anhydrous HCl(g) with trimethyl phosphane oxide yields trimethylhydroxy phosphonium chloride. A crystal structure analysis showed that the prevalent mesomeric structure in the solid state is the phosphonium chloride ion pair. Ab initio calculations in the gas phase cannot reproduce these findings, whereas higher correlated methods (CISD) and solvation models predict the experimental structure correctly.
Project description:Under anhydrous conditions and in the absence of a Lewis-base solvent, a zinc chloride complex with tri-tert-butyl-phosphane as the ?-bridged dimer is formed, viz. di-?-chlorido-bis-[chlorido-bis-(tri-tert-butyl-phosphane)zinc], [ZnCl4(C12H27P)2], (1), which features a nearly square-shaped (ZnCl)2 cyclic core and whose Cl atoms inter-act weakly with C-H groups on the phosphane ligand. In the presence of THF, monomeric di-chlorido-(tetra-hydro-furan-?O)(tri-tert-butyl-phosphane-?P)zinc, [ZnCl2(C4H8O)(C12H27P)] or [P(tBu3)(THF)ZnCl2], (2), is formed. This slightly distorted tetra-hedral Zn complex has weak C-H?Cl inter-actions between the Cl atoms and phosphane and THF C-H groups. Under ambient conditions, the hydrolysed complex tri-tert-butyl-phospho-nium aqua-tri-chlorido-zincate 1,2-di-chloro-ethane monosolvate, (C12H28P)[ZnCl3(H2O)]·C2H4Cl2 or [HPtBu3](+) [(H2O)ZnCl3](-)·C2H4Cl2, (3), is formed. This complex forms chains of [(H2O)ZnCl3](-) anions from hydrogen-bonding inter-actions between the water H atoms and Cl atoms that propagate along the b axis.
Project description:The title compound, [Fe(C(7)H(5)FN)Cl(C(3)H(9)P)(3)], was obtained as a product of the reaction of [Fe(Me(3)P)(4)] with a molar equivalent of (2-chloro-6-fluoro-phen-yl)methanimine in diethyl ether. This compound is sensitive to air, and rapidly decomposes when exposed to air for a few minutes. The Fe atom has an octa-hedral coordination geometry in which the bidentate fluoro-phenyl methanimine ligand forms the equatorial plane with the Cl atom and one of the trimethyl-phosphane ligands. The other two trimethyl-phosphane ligands are located in the axial positions. In the crystal, an N-H?Cl hydrogen bond occurs.
Project description:The aim of this work is to investigate extraction of ruthenium(III) from acidic aqueous solutions with phosphonium ionic liquids such as trihexyl(tetradecyl)phosphonium chloride (Cyphos IL 101), trihexyl(tetradecyl)phosphonium bis(2,4,4-trimethylpentyl)phosphinate (Cyphos IL 104) and tributyl(tetradecyl)phosphonium chloride (Cyphos IL 167) as extractants. The influence of HCl content in the feed solutions on extraction of Ru(III) was investigated. The research was performed for model solutions containing Ru(III) and a mixture of waste solutions containing Ru(III) and Rh(III). In addition, investigation of the type of extractant and its concentration in the organic phase on extraction of Ru(III) was carried out. Co-extraction of protons to the organic phase was determined. To the best of our knowledge, the extraction of Ru(III) with Cyphos IL 167 (tributyl(tetradecyl)phosphonium chloride) as an extractant has not yet been described in the scientific literature.
Project description:Mesoionics are neutral compounds that cannot be represented by a fully covalent or purely ionic structure. Among the possible mesomeric structures of these compounds are the diradical electronic configurations. Theoretical and experimental studies indicate that some mesoionic rings are unstable, which may be related to a significant diradical character, that until then is not quantified. In this work, we investigated the diradical character of four heterocycles: 1,3-oxazol-5-one, 1,3-oxazol-5-thione, 1,3-thiazole-5-one, and 1,3-thiazole-5-thione. The oxazoles are known to be significatively less stable than thiazoles. DFT and ab initio single (B3LYP, MP2, CCSD, and QCISD) and ab initio multi-reference (MR-CISD) methods with three basis sets (6-311+G(d), aug-cc-pVDZ, and aug-cc-pVTZ) were employed to assess the diradical character of the investigated systems, in gas phase and DMSO solvent, from three criteria: (i) HOMO-LUMO energy gap, (ii) determination of energy difference between singlet and triplet wave functions, and (iii) quantification of the most significant diradical character (y0, determined in the unrestricted formalism). All of the results showed that the diradical character of the investigated systems is very small. However, the calculated electronic structures made it possible to identify the possible origin of the oxazoles instability, which can help the design of mesoionic systems with the desired properties.
Project description:In the crystal structure of the title compound, [U(2)Cl(4)O(4)(C(2)H(6)OS)(4)], the compound has a centrosymmetric dimeric structure bridged by two chloride anions. Each U(VI) atom is seven-coordinate in a penta-gonal-bipyramidal geometry. In the equatorial plane of the uranyl unit there are two O atoms from non-adjacent dimethyl sulfoxides and three chloride ions (of which two chlorides are bridging). The compound is of inter-est as an anhydrous starting material of the uran-yl(VI) ion.
Project description:The title compound, C(11)H(12)N(2)OS, was synthesized from 2-amino-benzothia-zole and butanoyl chloride in anhydrous acetone. In the crystal structure, mol-ecules are linked by N-H?N and C-H?O hydrogen bonds and by C-H?? inter-actions.
Project description:The title compound, [Fe(C(4)H(2)N(2)S(2))(C(3)H(9)P)(2)(CO)(2)], was obtained as a mononuclear by-product during the treatment of [Fe(2)(?-S(2)C(4)N(2)H(2))(CO)(6)] in excess trimethyl-phosphane. The Fe atom is six-coordinated by two thiol-ate S atoms, two phosphane P atoms and two carbonyl C atoms in a distorted octa-hedral geometry. The average Fe-C(O) distance (1.771?Å) is relatively shorter than that of its parent hexa-carbonyl-diiron compound, and differs by 0.511?Å from the average Fe-P(Me)(3) distance. The five-membered FeC(2)S(2) chelate ring plane is close to being perpendicular to the P/Fe/P plane [86.5?(2)°].
Project description:IN THE CRYSTAL STRUCTURE OF THE TITLE ADDUCT [SYSTEMATIC NAME: 2-(1,3-dioxoisoindolin-2-yl)acetic acid-1,3,7-trimethyl-1,2,3,6-tetra-hydro-7H-purine-2,6-dione (1/1)], C(8)H(10)N(4)O(2)·C(10)H(7)NO(4), the components are linked by an O-H?N hydrogen-bond and no proton transfer occurs.
Project description:In the title compound, [Rh(C6H5N4)Cl2(C12H27P)2], the Rh(III) ion is chelated by the singly deprotonated 2,2'-biimidazolate (Hbim(-)) ligand and coordinated by two chloride ions and two tri-n-butyl-phosphane ligands. The chloride ions and N atoms of the Hbim(-) ligand lie in a plane where the sum of X-Rh-X angles between cis sites is 360°. The phosphane ligands occupy the sites perpendicular to the plane, completing the overall distorted octahedral coordination sphere. The complex forms a self-complementary hydrogen-bonded dimer with the inversion-related complex through N-H?N hydrogen bonds.
Project description:Upon reacting with tetrakis(hydroxymethyl) phosphonium chloride, 15 nm citrate gold nanoparticles rapidly assemble into linear chains, followed by slowly disassembling into monodisperse components. This work highlights the first example of (31)P NMR on gold particles of this size and suggests that the phosphonium is oxidized on-particle, contributing to particle disassembly.