Lewis-Säure/Base Addukte von TiCl4 und Methylpyridinen / Lewis Acid/Base Adducts of TiCl4 and Methylpyridines

2000 ◽  
Vol 55 (9) ◽  
pp. 877-881 ◽  
Author(s):  
Karl Hensen ◽  
Alexander Lemke ◽  
Michael Bolte
Keyword(s):  
Molecular Structure ◽  
Lewis Acid ◽  
Equatorial Position ◽  
Acid Base ◽  
Nitrogen Base ◽  
X Ray ◽  
Nitrogen Bases ◽  
Distorted Trigonal Bipyramid ◽  
In Trans ◽  
Ray Methods

By the reaction of 2-methyl- and 2,6-dimethylpyridine the first neutral TiCl4L complexes (L = single bonded ligand) could be synthesized. The structures have been determined by single crystal X-ray methods. The best description of the molecular structure is a distorted trigonal bipyramid with the nitrogen base occupying an equatorial position. With 2,4-dimethylpyridine, a 1:2 adduct is formed, where the nitrogen bases are in trans-positions of a TiCl4N2-octahedron, as also confirmed by an X-ray analysis

Notizen: Die Kristallstruktur des Rhenium-Tolankomplexes [ReCl4(PhC ≡ CPhXOPCl3)] / The Crystal Structure of the Rhenium-tolane Complex [ReCl4(PhC ≡ CPh)(OPCl3)]

1993 ◽  
Vol 48 (7) ◽  
pp. 1019-1022 ◽  
Author(s):  
Gerlinde Frenzen ◽  
Dorothea Wolff von Gudenberg ◽  
Kurt Dehnicke
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Oxygen Atom ◽  
Bond Length ◽  
Trans Position ◽  
X Ray ◽  
Bond Lengths ◽  
In Trans ◽  
Ray Methods ◽  
Ligand Bond

The crystal structure of [ReCl4(PhC = CPh)(OPCl3)] was solved with X-ray methods. Space group P1̄, Z = 2, 2085 observed unique reflections, R = 0.029. Lattice dimensions at -70°C: a = 857.0(2), b = 937.9(2), c = 1249.6(2) pm, α = 87.43(3)°, β = 83.48(3)°, γ = 89.80(3)°. [ReCl4(PhC ≡ CPh)(OPCl3)] has a molecular structure with the alkyne ligand bonded side-on (bond lengths Re-C 198.9(8) and 198.6(7) pm). The oxygen atom of the solvating POCl3 molecule is coordinated in trans position to the ReC2 unit of the alkyne ligand (bond length Re-O 226.7(5) pm).

Strukturuntersuchungen an Vierringsystemen, III* Kristall- und Molekülstrukturen von trans-2.4-Bis(trimethylsilyl)-2.4-dihydro- 1.3-dithietan-1.1.3.3-tetroxid, 2.2.4.4-Tetramethyl-3-pyrrolidinocyclobutanon und 2.2.4.4-Tetramethyl-1-phenyl-3-pyrrolidinoeyelobutanol/Structural Investigations on Four-Membered Ring Systems, III* Crystal and Molecular Structures of trans-2,4-Bis(trimethylsilyl)-2,4-dihydro-1,3-dithietane-1,1,3,3-tetroxide, 2,2,4,4-Tetramethyl-3-pyrrolidinocyclobutanone and 2,2,4,4-Tetramethyl-1-phenyl-3-pyrrolidinocyclobutanol

1982 ◽  
Vol 37 (8) ◽  
pp. 1005-1013 ◽  
Author(s):  
Barbara Balbach ◽  
Reinhold Alt ◽  
Manfred L. Ziegler
Keyword(s):  
Phenyl Group ◽  
Molecular Structures ◽  
Hydroxyl Group ◽  
Equatorial Position ◽  
Pyrrolidine Ring ◽  
Structural Investigations ◽  
X Ray ◽  
Crystal And Molecular Structures ◽  
In Trans ◽  
Ray Methods

Abstract The molecular structures of the title compounds have been determined by X-ray methods. In the bis(trimethylsilyl) substituted dithietane the (CH3)3Si groups are in trans position; the C2S2-ring is planar. In the cyclobutanone the pyrrolidine group occupies an equatorial position, as does the phenyl group in the cyclobutanol. In the latter the hydroxyl group is trans to the pyrrolidine ring. The four-membered carbon rings are folded.

Chalkogenolat-Ionen und ihre Derivate, V Kristall- und Molekülstruktur von 2.8-Dimethyldibenzo [c.g] [1.2.5.6] tetrathiacyclooktadien, einem Oxidationsprodukt von 4-Methylbenzol-1.2-dithiol/Chalcogenolates and their Derivatives, V Crystal and Molecular Structure of 2.8-Dimethyldibenzo[c,g][1,2,5,6]tetrathiaocin, an Oxidation Product of 4-Methylbenzene-1,2-dithiol

1979 ◽  
Vol 34 (1) ◽  
pp. 48-51 ◽  
Author(s):  
Jürgen Kopf ◽  
Klaus von Deuten ◽  
Bahman Nakhdjavan ◽  
Günter Klar
Keyword(s):  
Molecular Structure ◽  
Dihedral Angle ◽  
Oxidation Product ◽  
Crystal And Molecular Structure ◽  
X Ray ◽  
The Mean ◽  
Ray Methods ◽  
Anti Form

Abstract The structure of 2,8-dimethyldibenzo[c,g][1,2,5,6]tetrathiaocin (1b) has been determined by X-ray methods and discussed in connection with the preferred conformations of diaryl disulfides. The compound has the anti-form I. The SS-distance is 205.8 pm, the mean CSS-angle 104.1°, and the CSS/SSC-dihedral angle 111.1°.

An Intramolecular Boron Nitrogen Lewis Acid Base Pair on a Rigid Naphthyl Backbone

2012 ◽  
Vol 67 (6) ◽  
pp. 589-593 ◽  
Author(s):  
Daniel Winkelhaus ◽  
Beate Neumann ◽  
Norbert W. Mitzel
Keyword(s):  
Nmr Spectroscopy ◽  
Single Crystal ◽  
Lewis Acid ◽  
Elemental Analysis ◽  
Base Pair ◽  
Ring System ◽  
X Ray Diffraction ◽  
Acid Base ◽  
X Ray ◽  
Boron Nitrogen

The reaction of (C6F5)2BCl with 8-lithio-N,N-dimethyl-1-naphthylamine (1) afforded the fivemembered ring system 8-bis(pentafluorophenyl)boryl-N,N-dimethyl-1-naphthylamine (2) with an intramolecular dative B-N bond. The compound was characterised by elemental analysis, NMR spectroscopy and single-crystal X-ray diffraction.

Metalltetrahydridoborate und Tetrahydridometallate, 11 [1] Zur Kristall- und Molekülstruktur von Magnesiumtetrahydridoborat Mg(BH4)2 • 3 THF / Metal Tetrahydridoborates and Tetrahydridoborato Metallates, 11 [1] The Crystal and Molecular Structure of Magnesium Tetrahydridoborate Mg(BH4)2 • 3 THF

1982 ◽  
Vol 37 (12) ◽  
pp. 1499-1503 ◽  
Author(s):  
Heinrich Nöth
Keyword(s):  
Molecular Structure ◽  
Crystal Structure ◽  
Oxygen Atom ◽  
Coordination Polyhedron ◽  
Crystal And Molecular Structure ◽  
Equatorial Position ◽  
Crystallographic Axis ◽  
Space Group ◽  
Distorted Trigonal Bipyramid ◽  
Double Hydrogen

Mg(BH4)2 • 3 THF was prepared from MgHo and B2H6 in tetrahydrofuran. It crystallizes monoclinically, space group C2/c, Z = 4. The crystal structure reveals that the molecule contains a seven-coordinate Mg center. Its BH4 groups form double hydrogen bridges to magnesium. The geometry at Mg corresponds to a slightly distorted trigonal bipyramid for the O 3 B 2 (Mg)-coordination polyhedron, with two THF molecules in apical and one in equatorial position. A two-fold crystallographic axis passes through Mg and the equatorial oxygen atom thus posing C2 symmetry on the molecule

scholarly journals IX—investigations on magne-crystallic action III—Further studies on organic crystals

1935 ◽  
Vol 234 (739) ◽  
pp. 265-298 ◽  
Keyword(s):  
Molecular Structure ◽  
Crystal Lattice ◽  
Convenient Method ◽  
Organic Crystals ◽  
Double Refraction ◽  
Magnetic Susceptibilities ◽  
X Ray ◽  
Benzene Rings ◽  
The Individual ◽  
Ray Methods

In Part I* of this paper a convenient method of measuring the principal magnetic susceptibilities of single crystals was described, and several organic crystals, among others, were studied by this method. The results were discussed particularly in relation to the structure of the molecules and their orientations in the crystal lattice, and it was shown how a correlation of the principal magnetic susceptibilities of the crystal with those for the individual molecules (obtained from measurements on magnetic double-refraction in the liquid state, or from considerations of molecular structure) gives us useful information regarding the orientations of the molecules in the crystal lattice. Indeed, in favourable cases the molecular orientations may thus be determined much more easily, and some of the parameters defining the orientations also more accurately, than by X-ray methods of analysis. Conversely, where the molecular orientations in the crystal lattice are already known from X-ray studies, a knowledge of the principal magnetic susceptibilities of the crystal enables us to obtain the magnetic constants of the individual molecules, which are of interest. For example, it is thus found that as one proceeds from benzene to naphthalene and from naphthalene to anthracene, the numerical increase in susceptibility that occurs, is directed predominantly along the normal to the plane of the benzene rings

η3- Allymetall-Schwefel-Cluster des Nickels, Palladiums und Platins / η3-Allyl Metal Sulfur Cluster Compounds of Nickel, Palladium, and Platinum

1979 ◽  
Vol 34 (4) ◽  
pp. 609-613 ◽  
Author(s):  
Borislav Bogdanović ◽  
Richard Goddard ◽  
Peter Göttsch ◽  
Carl Krüger ◽  
Klaus Schlichte ◽  
...  
Keyword(s):  
Molecular Structure ◽  
Structural Similarity ◽  
Molecular Data ◽  
Cluster Compounds ◽  
Sulfur Cluster ◽  
Space Group ◽  
X Ray ◽  
Coordination Sites ◽  
Cell Data ◽  
Ray Methods

AbstractNovel cluster compounds of the composition [(η3-C3H5)2M2S]x, wherein M represents nickel, palladium or platinum are obtained by reaction of 2,5-disubstituted-1,6,6a-trithiopentalenes or H2S with (η3-C3H5)2M in THF solution. The molecular structure of one of these new cluster types [(η3-C3H5Ni)2S]3 has been established by X-ray methods. It is best described as being a fraction of a NiS-framework in which peripheral coordination sites are occupied by partial disordered η3-allyl groups. Molecular data (cell data: a = 19.868(4), b = 8.988(2), c = 14.501(3) Å, β = 115.30(2)°, space group C2/c, Z = 4, R = 0.106) are compared with the parent Bs-NiS lattice. Spectroscopic evidence for the structural similarity of the related Pd- and Pt-compounds is given.

A Ring Destruction Approach to Some Benzo-Fused Medium-Sized Heterocycles by Means of Cyanogen-Bromide Under Solvolytic Conditions - X-Ray Structure of a '1h-2,6-Benzoxazecine-6-Carbonitrile and a '2h-3,6-Benzoxazecine-6-Carbonitrile Derivative

1986 ◽  
Vol 39 (6) ◽  
pp. 893 ◽  
Author(s):  
JB Bremner ◽  
CL Raston ◽  
GL Rowbottom ◽  
AH White ◽  
KN Winzenberg
Keyword(s):  
Molecular Structure ◽  
Tertiary Amine ◽  
Cyanogen Bromide ◽  
Crystal And Molecular Structure ◽  
X Ray ◽  
Concomitant Reduction ◽  
Heterocyclic Derivatives ◽  
Isoquinoline Derivatives ◽  
Ray Methods ◽  
Medium Ring

Reaction of the reduced pyrrolo [2,1-a] isoquinoline amine (1a) with cyanogen bromide in the presence of methanol gave the medium-ring cyanamide derivative 7,9,10-trimethoxy-2,3,4,5,6,7-hexahydro-1H-3- benzazonine-3-carbonitrile (2a). Analogous products were also obtained from reaction of the reduced 5H-oxazolo[2,3-a] isoquinoline , 2H- benzo [a] quinolizine , 2H,6H-[1,3] oxazino [2,3-a] isoquinoline and [1,4] oxazino [3,4-a] isoquinoline derivatives (1b-e), whereas the reduced 3H-oxazolo[4,3-a] isoquinoline and 5H-oxazolo[2,3-a] isoquinoline derivatives (1f) and (8) gave 1-(2,4-dioxapentyl)-6,7-dimethoxy-1,2,3,4-tetrahydroisoquinoline-2-carbonitrile (5a) and N-[2-(2-benzoyl-4,5-dimethoxyphenyl)ethyl]-N- methylcyanamide (9) respectively, the latter in low yield. The medium-sized heterocyclic derivatives (2f-h) were also obtained from cyanogen -bromide-mediated water solvolysis reactions of (1a), (1c) and (1e). The cyanamides (2a-h), (5a) and (9) have been converted into the respective tertiary amine derivatives (3a- h), (5c) and (11), with concomitant reduction of the carbonyl group in the last case. The crystal and molecular structure of 1,10,11- trimethoxy-3,4,5,6,7,8-hexahydro-1H-2,6-benzoxazecine-6-carbonitrile (2d) and 1-hydroxy-10,11-dimethoxy-1,4,5,6,7,8-hexahydro-2H-3,6- benzoxazecine-6-carbonitrile (2h) have been determined by single- crystal X-ray methods.

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