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Trigonal Bipyramidal Geometry (trigonal + bipyramidal_geometry)

Distribution by Scientific Domains
Chemistry100%

Kinds of Trigonal Bipyramidal Geometry

  • distorted trigonal bipyramidal geometry
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    Selected Abstracts

    Relative energies of conformations and sulfinyl oxygen-induced pentacoordination at silicon in 4-bromo- and 4,4-dibromo-4-silathiacyclohexane 1-oxide: A computational study

    INTERNATIONAL JOURNAL OF QUANTUM CHEMISTRY, Issue 4 2005
    Fillmore Freeman
    Abstract The equilibrium geometries and relative energies of the chair, twist, and boat conformations of cis - and trans -4-bromo-4-silathiacyclohexane 1-oxide and 4,4-dibromo-4-silathiacyclohexane 1-oxide have been calculated at the B3LYP/6-311G(d,p) and MP2/6-311+G(d,p) theoretical levels. The axial (SO) chair conformers of the sulfoxides are of lower energy than the chair conformers of the corresponding equatorial (SO) sulfoxides. The chair conformer of the axial (SO) trans -4-bromo-4-silathiacyclohexane 1-oxide is only 0.10 kcal/mol more stable than the corresponding 1,4-boat conformer which is stabilized by a transannular coordination of the sulfinyl oxygen with silicon that results in trigonal bipyramidal geometry at silicon. The 1,4-boat structure of equatorial (SO) trans -4-bromo-4-silathiacyclohexane 1-oxide is a transition state and is 5.77 kcal/mol higher in energy than the respective chair conformer. The 1,4-boat conformer of axial (SO) 4,4-dibromo-4-silathiacyclohexane 1-oxide is also stabilized by transannular coordination of the sulfinyl oxygen and silicon, but it is 4.31 kcal/mol higher in energy than the corresponding chair conformer. The relatively lower stability of the 1,4-boat conformer of 4,4-dibromo-4-silathiacyclohexane 1-oxide may be due to repulsive interactions of the axial halogen and sulfinyl oxygen atom. The relative energies of the conformers and transition states are discussed in terms of hyperconjugative interactions, orbital interactions, nonbonded interactions, and transannular sulfinyl oxygen-silicon coordination. © 2005 Wiley Periodicals, Inc. Int J Quantum Chem, 2005 [source]

    Aerobic, Chemoselective Oxidation of Alcohols to Carbonyl Compounds Catalyzed by a DABCO-Copper Complex under Mild Conditions

    ADVANCED SYNTHESIS & CATALYSIS (PREVIOUSLY: JOURNAL FUER PRAKTISCHE CHEMIE), Issue 14-15 2007
    Sreedevi Mannam
    Abstract A DABCO-copper(I) chloride complex (5 mol,%) together with TEMPO (5 mol,%) in nitromethane as solvent has been used as an efficient catalytic system for the selective oxidation of benzylic and allylic alcohols into the corresponding carbonyl compounds at room temperature where molecular oxygen acts as an ultimate, stoichiometric oxidant and water is the only by-product. The solid-state structure determination of the DABCO-copper complex shows that the copper is in the +II oxidation state with trigonal bipyramidal geometry and exists in a linear polymeric structure due to strong hydrogen bonding. [source]

    Ecofriendly synthesis, antimicrobial and antispermatogenic activity of triorganotin(IV) complexes with 4,-nitrobenzanilide semicarbazone and 4,-nitrobezanilide thiosemicarbazone

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2009
    Pratibha Chaudhary
    Abstract New series of triorganotin(IV) complexes with 4,-nitrobenzanilide semicarbazone (L1H) and 4,-nitrobenzanilide thiosemicarbazone (L2H) of the type [R3Sn(L)] (R = -CH3, -C6H5 and n -C4H9) were synthesized under microwave irradiation. All the complexes were characterized by elemental analysis, conductance measurements, molecular weight determinations and spectral data, viz., IR, UV,vis, 1H, 13C and 119Sn NMR. The central tin atoms of these complexes are all five-coordinated with trigonal bipyramidal geometry. In order to assess their growth inhibitory potency semicarbazone, thiosemicarbazone and their triorganotin(IV) complexes were tested in vitro against some pathogenic fungi and bacteria. Also the ligands and their organotin(IV) complexes were studied to assess the effects of long-term ingestion of these compounds on fertility, body and reproductive organ weights. The biochemical analyses were also performed on blood samples and reproductive organs of male rats. The findings have been presented in this paper. Copyright © 2009 John Wiley & Sons, Ltd. [source]

    Synthesis, structural characterization and cytotoxic activity of diorganotin(IV) complexes of N -(5-halosalicylidene)tryptophane

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 1 2009
    Laijin Tian
    Abstract Four new diorganotin(IV) complexes of N -(5-halosalicylidene)tryptophane, R2Sn[5-X-2-OC6H3CHNCH(CH2Ind)COO] [Ind = 3-indolyl; R, X = Et, Cl (1); Et, Br(2); n -Bu, Cl (3); n -Bu, Br (4)], were synthesized and characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectra. The crystal structures of complexes 1,3 were determined by X-ray single crystal diffraction and showed that the tin atoms are in a distorted trigonal bipyramidal geometry and form five- and six-membered chelate rings with the tridentate ligand. Intermolecular weak interactions in 1,3 link molecules, respectively, into a two-dimensional array, a one-dimensional infinite chain and a one-dimensional double-chain supramolecular structure. Bioassay results of the compounds indicated that the dibutyltin complexes 3 and 4 have potent in vitro cytotoxic activity against two human tumor cell lines, CoLo205 and Bcap37, while the diethyltin complexes 1 and 2 display weak cytotoxic activity. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Behavioural dynamics in the biological control of pests: role of silicon complexes

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 11 2008
    Savita Belwal
    Abstract The complexes of silicon (IV) with Schiff base ligands (L1H and L2H of isatin derivatives) having a sulfur and oxygen donor system were prepared by the reactions in methanol environment. These were isolated and characterized by elemental analysis, molecular weight determinations and conductance measurements. On the basis of electronic, infrared, 1H, 13C and 29Si NMR spectral studies, trigonal bipyramidal geometry was suggested for the resulting complexes. These data support preferential binding of sulfur and oxygen atom to the silicon atom. The disease resistance activities of the ligands and their corresponding complexes were examined successfully in in vitro and in vivo experiments, against pathogenic fungi and bacteria. Results were quite encouraging and these were compared with the standard pesticides Bavistin and Streptomycin. Copyright © 2008 John Wiley & Sons, Ltd. [source]

    Synthesis, characterization and biological activity of diphenyltin(IV) complexes of N -(3,5-dibromosalicylidene)-,-amino acid and their diphenyltin dichloride adducts

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 1 2006
    Laijin Tian
    Abstract Diphenyltin(IV) complexes of N -(3,5-dibromosalicylidene)-,-amino acid, Ph2Sn[3,5-Br2 -2-OC6H2 CHNCH(R)COO] (where R = H, Me, i -Pr, Bz), and their 1:1 adducts with diphenyltin dichloride, Ph2Sn[3,5-Br2 -2-OC6H2CHNCH(R)COO]·Ph2SnCl2, have been synthesized and characterized by elemental analysis, IR and NMR (1H, 13C and 119Sn) spectra. The crystal structure of Ph2Sn[3,5-Br2 -2-OC6H2CHNCH(i -Pr)COO] shows a distorted trigonal bipyramidal geometry with the axial locations occupied by a carboxylate,oxygen and a phenolic,oxygen atom of the ligand, and that of Ph2Sn[3,5-Br2 -2-OC6H2CHNCH(i -Pr)COO]·Ph2SnCl2 reveals that the two tin atoms are joined via the carbonyl atom of the ligand to form a mixed organotin binuclear complex. Bioassay indicates that the compounds possess better cytotoxic activity against three human tumor cell lines (HeLa, CoLo205 and MCF-7) than cis -platin and moderate antibacterial activity against two bacteria (E. coli and S. aureus). Copyright © 2005 John Wiley & Sons, Ltd. [source]

    Crystallographic report: 2-Furfurylgermatrane

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 4 2004
    Edmunds Lukevics
    Abstract The germanium atom is penta-coordinated and adopts a trigonal bipyramidal geometry. The 2-furfuryl group and the nitrogen atom each occupy an apical position with a transannular N,Ge bond distance of 2.173(3) Å. Copyright © 2004 John Wiley & Sons, Ltd. [source]

    Di- n -butyltin(IV) derivatives of bis(carboxymethyl)benzylamines: synthesis, NMR and X-ray structure characterization and in vitro antitumour properties

    APPLIED ORGANOMETALLIC CHEMISTRY, Issue 7 2001
    Teresa Mancilla
    Abstract Four di- n -butyltin(IV) derivatives of bis(carboxymethyl)benzylamines were synthesized and their structure characterized by 1H,13C and ­117/119Sn NMR, Mössbauer spectroscopy and mass spectrometry. The derivative substituted in the meta position by a methyl group has been further characterized by X-ray crystallography. This compound exhibits a distorted trigonal bipyramidal geometry at tin. The NMR data in solution, as well as other spectroscopic results in the solid state, confirm this structure for all the compounds. Evidence is provided to show that the compounds are more highly associated in concentrated solution than in the solid state. Their in vitro antitumour activity is reported. Copyright © 2001 John Wiley & Sons, Ltd. [source]

    Synthesis and Characterization of Three Diverse Coordination Frameworks under Co-ligand Intervention

    CHINESE JOURNAL OF CHEMISTRY, Issue 2 2009
    Ping LIU
    Abstract The chelating organic ligands of 2,2,-bipyridine (2,2,-bipy), di(pyrid-2-yl)amine (dpa) and 2,6-di(pyrid-2-ylamino)pyridine (dpap) were respectively applied to react with H2fum (fumaric acid) and copper salts, affording three different complexes [Cu2(fum)(2,2,-bipy)4]·2ClO4 (1), [Cu2(µ-OH)2(fum)(dpa)2]·2H2O (2) and [Cu(SO4)(H2O)(dpap)]·H2O (3). These complexes were determined by single-crystal X-ray diffraction. Each penta-coordinated Cu(II) ion exhibits a distorted trigonal bipyramidal geometry in 1. The fum ligand links copper ions to form a dinuclear copper unit. While in 2, the fum ligands connect [Cu2(µ-OH)2(dpa)2] unit to construct a 1D zigzag chain. Unexpectedly, when dpap instead of dpa was used under the same conditions, only one mononuclear complex 3 was formed. Crystal packings show that 1,3 form 3D supramolecular architectures through non-covalent interactions (multiple hydrogen bonds and C,H··· ,/,-, interactions). In addition, the study of the magnetic property reveals dominating ferromagnetic interactions between Cu(II) atoms in 1. [source]