Spectroscopic studies of triphenyltin azide and of its adducts with O- and N-donor ligands; the crystal and molecular structures of triphenyltin azide and of azido(hexamethylphosphoramide)triphenyltin(IV)

1998 ◽  
Vol 76 (12) ◽  
pp. 1827-1835 ◽  
Author(s):  
Ivor Wharf ◽  
Ryszard Wojtowski ◽  
Carol Bowes ◽  
Anne-Marie Lebuis ◽  
Mario Onyszchuk

Complete far-IR and Raman data (<400 cm-1) are reported for triphenyltin azide (1) as well as for adducts Ph3SnN3·L (L = hexamethylphosphoramide (HMPA), triphenylphosphine oxide, pyridine-N-oxide, 4-picoline-N-oxide, or pyridine). The small changes in v(Sn-N3) noted on going from (1) to the adducts, as well as solid-state 119Sn nmr data, indicate that (1), like the adducts, has five-coordinate tin atoms. X-ray analysis shows that (1) crystallizes with two different chains of five-coordinate Ph3Sn units joined by 1,3-azide bridges. In one unit, the geometry around tin is similar to that found for the monomeric HMPA adduct (2), which has trans-axial HMPA and azide ligands. The other unit in (1) has nonplanar -SnC3- groups connected by less symmetric 1,3-azide bridges and thus resembles the structure of isoelectronic triphenyltin isocyanate.Key words: triphenyltin azide, O- and N-donor adducts, far-IR/Raman, crystal structures.

2000 ◽  
Vol 55 (11) ◽  
pp. 1005-1010 ◽  
Author(s):  
Ulrich Jürgen Bildmann ◽  
Martin Winkler ◽  
Gerhard Müller Fachbereich

The crystal and molecular structures of the phosphinomethyl-substituted lithium cyclopentadienides [Li(tmeda)][R2PCMe2C5H4], R = Ph (1), Me (2) (tmeda = N,N,N',N'-tetramethylethylenediamine) were determined as their tmeda adducts on the basis of low temperature single crystal X-ray diffraction. (Crystal data: 1: monoclinic, space group P21/n, a = 8.511(5), b = 11.936(2), c = 24.20(1) Å, β = 90.02(3)°, Z = 4.2: monoclinic, space group P21/n, a = 10.887(2), b = 13.326(2), c = 13.131(2) Å, β= 92.872(6)°, Z = 4). In both compounds lithium has a slightly distorted 17 coordination to the cyclopentadienide (Cp) ring. There are no interactions between lithium and the phosphine donors in the solid state as the phosphinomethyl substituents are oriented to the other side of the Cp ring for steric reasons. The isopropene-substituted lithium cyclopentadienide, which is formed as a by-product in the synthesis of phosphinomethyl cyclopentadienides containing a CMe2 bridge, was also structurally characterized as its tmeda adduct [Li(tmeda)][H2C=CMeC5H4] (3). (Crystal data: monoclinic, P21/c, a = 8.00(2), b = 16.701(2), c = 11.942(6) Å, β= 112.68(7)°, Z = 4). As in 1 and 2, lithium is η5 -coordinated to the Cp ring, and there is no interaction of the functional group (isopropene) with lithium.


Author(s):  
A.V. Yatsenko ◽  
K.A. Paseshnichenko ◽  
S.I. Popov

The crystal and molecular structures of 2-methyl-1-methylamino-anthraquinone (I) and 1-methylphenylamino-anthraquinone (II) were studied by the X-ray single-crystal diffraction and the visible spectra of crystalline specimens and their solutions were recorded. The molecule I is closely planar, whereas in the molecule II the amino group is 58° rotated out of the plane of the anthraquinone skeleton. In both structures the molecules pack in stacks. The comparison of experimental and calculated (on the DFT and AM1 levels) molecular structures, together with the comparison of experimental and INDO/S-calculated electronic spectra, give the evidence that molecular conformations (especially for II) change upon transfer from the solid state to solutions, and the π-delocalisation throughout the whole molecule enhances in the solid state.


2010 ◽  
Vol 65 (2) ◽  
pp. 119-127 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Ezzat Khan ◽  
Amin Badshah ◽  
Elias Molla ◽  
Peter Thoma ◽  
...  

The molecular structures of three alkynylsilanes, tetrakis(ethynyl-p-tolyl)silane, 3,3,6,6,-tetramethyl- 3,6-disila-triyne, 3,3,6,6,9,9,-hexamethyl-3,6,9-trisila-tetrayne, and of bis(trimethylstannyl)- ethyne have been determined by X-ray diffraction. The same alkynylsilanes, and in addition 1,2- bis(trimethylsilylethynyl)-1,1,2,2-tetramethyldisliane, were studied by solid-state 13C and 29Si MAS NMR spectroscopy. The results of these measurements were compared with crystallographic evidence and also with relevant solution-state NMR data.


2007 ◽  
Vol 72 (12) ◽  
pp. 1281-1293 ◽  
Author(s):  
Vukadin Leovac ◽  
Zoran Tomic ◽  
Katalin Mészáros-Szécsényi ◽  
Ljiljana Jovanovic ◽  
Milan Joksovic

The crystal and molecular structures of four tetrahedral structurally similar [Co(aamp)2X2] complexes (aamp = 4-acetyl-3-amino-5-methylpyrazole, X = Cl, Br, I and NCS) were determined by X-ray diffraction analysis and are discussed in detail. It was found that the different capacity of the ligand X (NCS vs. Cl, Br, I) for the formation of non-bonding contacts influence the mode of molecular association in the solid state. The complexes were characterized by UV-Vis spectroscopy. The first step of the thermal decomposition of the compounds was checked and is discussed in the view of the IR spectrum of the intermediate isolated from [Co(aamp)2Br2] by the quasi-isothermal technique.


1991 ◽  
Vol 46 (11) ◽  
pp. 1532-1538 ◽  
Author(s):  
Theodoros F. Zafiropoulos ◽  
John C. Plakatouras ◽  
S. P. Perlepes

Synthetic procedures are described that allow access to anilinium salts containing the complex anions [Hg2Cl62-, [Hg2Cl4X2]2- (X = Br, I), [CdHgI6]2-, [CdHgI4Br2]2- and [CdHgBr4I2]2--. Isolated dimeric structures are proposed for the new complexes in the solid state, using X-ray powder patterns, Far-IR and Raman spectra. The spectral detail is greatly enhanced in measurements at low temperature (∼100 K).


Author(s):  
Volker Böhmer ◽  
Helmut Goldmann ◽  
Walter Vogt ◽  
Erich F. Paulus ◽  
Fred L. Tobiason ◽  
...  

1996 ◽  
Vol 49 (3) ◽  
pp. 391 ◽  
Author(s):  
P Koll ◽  
J Kopf

The solid-state structures of the title compounds were determined by conventional single-crystal X-ray crystallography. In both cases a planar zigzag conformation of the carbon skeleton is observed with a resulting 1,3-parallel orientation of O(2) and O(4). In the case of the heptaacetate even a second such arrangement is established between O(3) and one of the oxygens at C(1). These findings substantiate the claim that such conformations are not as unfavourable as previously was assumed by many authors.


1985 ◽  
Vol 38 (1) ◽  
pp. 97
Author(s):  
H Becker ◽  
CL Raston ◽  
BW Skelton ◽  
AH White

The crystal and molecular structures of [1]benzopyrano[4,3- c][1]benzopyran-5,11-done (dibenzo-naphthyrone) and three of its symmetrically tetrasubstituted derivatives have been determined by single-crystal X-ray diffraction methods. Only the tetra-t-butyl-substituted dibenzonaphthyrone was found to deviate significantly from planarity by having the two carbonyl groups folded and 'syn'-oriented relative to the plane of the connecting ethylene double bond. The dihedral angle between the two aromatic rings was found to be 25. The molecular geometry of all the other dibenzo-naphthyrones in their crystalline states is characterized by planarity, and their structures are centrosymmetric.


2018 ◽  
Author(s):  
Katherine Marczenko ◽  
James Goettel ◽  
Gary Schrobilgen

Oxygen coordination to the Xe(VI) atom of XeO<sub>3</sub> was observed in its adducts with triphenylphosphine oxide, dimethylsulfoxide, pyridine-N-oxide, and acetone. The crystalline adducts were characterized by low-temperature, single-crystal X-ray diffraction and Raman spectroscopy. Unlike solid XeO<sub>3</sub>, which detonates when mechanically or thermally shocked, the solid [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3</sub>, [(CH<sub>3</sub>)<sub>2</sub>SO]<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub>,<sub> </sub>and (C<sub>5</sub>H<sub>5</sub>NO)<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> adducts are insensitive to mechanical shock, but undergo rapid deflagration when ignited by a flame. Both [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3 </sub>and (C<sub>5</sub>H<sub>5</sub>NO)<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> are air-stable whereas [(CH<sub>3</sub>)<sub>2</sub>SO]<sub>3</sub>(XeO<sub>3</sub>)<sub>2</sub> slowly decomposes over several days and [(CH<sub>3</sub>)<sub>2</sub>CO]<sub>3</sub>XeO<sub>3</sub> undergoes adduct dissociation at room temperature. The xenon coordination sphere of [(C<sub>6</sub>H<sub>5</sub>)<sub>3</sub>PO]<sub>2</sub>XeO<sub>3</sub> is a distorted square pyramid which provides the first example of a five-coordinate XeO<sub>3</sub> adduct. The xenon coordination spheres of the remaining adducts are distorted octahedra comprised of three Xe---O secondary contacts that are approximately trans to the primary Xe–O bonds of XeO<sub>3</sub>. Quantum-chemical calculations were used to assess the Xe---O adduct bonds, which are predominantly electrostatic σ-hole bonds between the nucleophilic oxygen atoms of the bases and the σ-holes of the xenon atoms.


1981 ◽  
Vol 34 (10) ◽  
pp. 2139 ◽  
Author(s):  
AJ Finney ◽  
MA Hitchman ◽  
CL Raston ◽  
GL Rowbottom ◽  
AH White

The preparation of a series of novel compounds of general formula [Ni5L4(NO2)8(OH)2] formed by ethane-1,2-diamine or one of five N-substituted ethane-1,2-diamines (L) is described. The crystal and molecular structures of the ethane-1,2-diamine, N,N'-diethylethane-1,2-diamine and N,N-dimethylethane-1,2-diamine complexes are reported. Each compound contains a planar, pentameric arrangement of nickel(II) ions, linked by bridging hydroxide and nitrite ligands. The details of the nitrite bridges differ among the complexes, causing differences in their electronic and infrared spectra. The structural variations are probably caused by the differing steric requirements of the amine substituents.


Sign in / Sign up

Export Citation Format

Share Document