Über die Reaktion von C(NMe2)4 mit zweikernigen Übergangsmetallcarbonylen; Kristallstrukturen von [C(NMe2)3][Mn(CO)5] und [C(NMe2)3][Co(CO)4] / On the Reaction of C(NMe2)4 with Binuclear Transition Metal Carbonyls: Crystal Structures of [C(NMe2)3][Mn(CO)5] and [C(NMe2)3][Co(CO)4]

1991 ◽  
Vol 46 (3) ◽  
pp. 297-302 ◽  
Author(s):  
Wolfgang Petz ◽  
Frank Weller
Keyword(s):  
Transition Metal ◽  
Crystal Structures ◽  
Structure Determination ◽  
Metal Carbonyls ◽  
Space Group ◽  
X Ray ◽  
Transition Metal Carbonyls ◽  
C Nmr

The reactions of C(NMe2)4 (1) with Mn2(CO)10 or Co2(CO)8 in THF yield[C(NMe2)3][Co(CO)4] (3) and [C(NMe2)3][Mn(CO)5] (4), respectively. The compounds Co(CO)4NMe2 (5) and Mn(CO)5NMe2 (6) could not be found. With CH2Cl2 4 is quantitatively converted into [C(NMe2)3][Mn(CO)4Cl2] (7) as shown by IR and 13C NMR investigations. 3 and 4 were characterized by an X-ray structure determination. 3: Space group Pnma, Z = 4, a = 7.435(2), b = 10.79(2), c = 20.299(5)Å. 4: Space group C2/c, Z = 4, a = 11.378(2), b = 10.165(1), c = 14.533(1) Å; β = 103.37(1)°. The compounds form independent ions with no bonding interactions between cation and anion; the central CN3 unit of the [C(NMe2)3]+ cation in 3 and 4 is disordered.

Zur Struktur und Dotierung von Selenosilikaten: die Kristallstruktur von Er2SeSiO4 und Er3,75Ca0,25Se2,75Cl0,25Si2O7 Structure and Doping of Seleno Silicates: the Crystal Structures of Er2SeSiO4 and Er3,75Ca0,25Se2,75Cl0,25Si2O7

1994 ◽  
Vol 49 (6) ◽  
pp. 733-740 ◽  
Author(s):  
Klaus Stöwe
Keyword(s):  
Crystal Structures ◽  
Structure Analysis ◽  
Rare Earths ◽  
Structure Determination ◽  
Lattice Parameters ◽  
Energy Dispersive ◽  
Space Group ◽  
X Ray ◽  
By Products

Well-shaped brown and pink isometric crystals were obtained as by-products of the synthesis of erbium selenides from the elements in evacuated and sealed silica ampoules with graphite inlets. They could be identified as erbium seleno mono- and disilicates by energy dispersive X-ray fluorescence and X-ray structure determination. The monosilicate Er2SeSiO4 crystallizes isotypically to Nd2SeSiO4 in the space group Pbcm with the lattice parameters a = 600.2(2), b = 688.0(2), c = 1075.2(2) pm and represents the second known seleno inosilicate of the rare earths. From X-ray structure analysis an isotypic relation between the disilicate Er3,75Ca0,25Se2,75Cl0,25Si2O7 and the compound Sm4S3Si2O7 was found, the former crystallizing in the space group I41/amd with the lattice parameters a - 1177.7(2) and c = 1376.5(2) pm. The doping o f the sorosilicate with the elements Ca and Cl originated from contam inations in the graphit inlets used in the procedure

Reaction of transition metal carbonyls with soluble polyselenides: synthesis and structure of [(C6H5)4P]2[Re2(Se4)2(CO)6]

1989 ◽  
Vol 67 (11) ◽  
pp. 1980-1983 ◽  
Author(s):  
Samuel C. O'Neal ◽  
William T. Pennington ◽  
Joseph W. Kolis
Keyword(s):  
Transition Metal ◽  
Metal Atom ◽  
Octahedral Coordination ◽  
Crystalline Solid ◽  
Metal Carbonyls ◽  
Coordination Environment ◽  
Space Group ◽  
Transition Metal Carbonyls ◽  
Zintl Ions

The reaction of rhenium decacarbonyl with polyselenide anions in DMF solution has been investigated. Two equivalents of K2Se3 react with Re2(CO)10 in DMF solution at 100 °C, in the presence of excess [(C6H5)4P]Br, to produce [(C6H5)4P]2[Re2(Se4)2(CO)6]. This can be isolated as an analytically pure red crystalline solid in 25% yield. The compound has been characterized crystallographically; space group P21/n, Z = 2, a = 12.052(3) Å, b = 14.619(5) Å, c = 16.159(4) Å, β = 98.31(2)°, V = 2817(1) Å3, R = 0.0583, Rw = 0.0653. In addition to two well-separated tetraphenylphosphonium counterions, the compound consists of the [Re2(Se4)2(CO)6]2− dianion. This molecule is a rhenium dimer with each metal coordinated to three CO ligands and a Se42− chain. One end of the chelating tetraselenide chain is bridging both rhenium atoms, completing an octahedral coordination environment around each metal atom. The bridging distances are slightly asymmetric, leading to the suggestion that the bridging selenide has some dative character. Keywords: selenides, rhenium carbonyls, Zintl ions, p-block clusters.

Synthesis, crystal structure determination, and spectroscopic analyses of 1-chloro-2-(2,6-diisopropylphenyl)-4,4-dimethyl-2-azaspiro[5.5]undecane-3,5-dione: an unyielding precursor to a cyclic (alkyl)(amido)carbene

2021 ◽  
Vol 77 (7) ◽  
Author(s):  
Todd W. Hudnall ◽  
Eric W. Reinheimer ◽  
Christopher L. Dorsey
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Structure Determination ◽  
Crystal Structure Determination ◽  
Close Inspection ◽  
Precursor Molecule ◽  
X Ray ◽  
Spectroscopic Analyses ◽  
C Nmr

The synthesis, single-crystal X-ray structure, and 1H and 13C NMR spectrocopic analyses of an unyielding precursor molecule to a cyclic (alkyl)(amido)carbene, 1-chloro-2-(2,6-diisopropylphenyl)-4,4-dimethyl-2-azaspiro[5.5]undecane-3,5-dione, C24H34ClNO2 (1), is reported. Despite the use of several bases, 1 could not be deprotonated to afford the corresponding carbene. The crystal structure of 1 was compared to the crystal structures of two structurally similar HCl adducts of stable carbenes (compounds 4 and 5), which revealed no significant differences in the geometries about the `carbene' C atoms. To better understand the reactivity differences observed for 1 when compared to 4 and 5, modified percent buried volume (%V bur) calculations were performed. These calculations revealed that the H atom bound to the carbene C atom is the most sterically hindered in compound 1 when compared to 4 and 5 (%V bur = 84.9, 81.3, and 79.3% for 1, 4, and 5, respectively). Finally, close inspection of the quadrant-specific %V bur values indicated that the approach of a deprotonating base to the H atom bound to the carbene C atom is significantly blocked in 1 (69.9%) when compared to 4 and 5 (50.4 and 56.5%, respectively).

Synthese und Kristallstrukturen von Diazadien-Komplexen der Erdalkalimetalle / Syntheses and Crystal Structures of Diazadiene Complexes of the Alkaline Earth Metals

1995 ◽  
Vol 50 (1) ◽  
pp. 71-75 ◽  
Author(s):  
Volker Lorenz ◽  
Bernhard Neumüller ◽  
Karl-Heinz Thiele
Keyword(s):  
Crystal Lattice ◽  
Crystal Structures ◽  
Structure Determination ◽  
Alkaline Earth ◽  
Alkaline Earth Metals ◽  
The Other ◽  
Calcium Atom ◽  
Space Group ◽  
X Ray ◽  
Moisture Sensitive

(DME)2] 1 (R = C6H4-4-CH3; DME = dimethoxyethane) was prepared by reaction of calcium with NR=CPh-CPh=NR in DME solution. The compound forms orange, moisture sensitive crystals, which were characterized by an X-ray structure determination [space group orthorhombic, P212121, Z = 4, 4634 observed unique reflections, R = 0.046; lattice dimensions at –70 °C: a = 1340.2(3), b = 1528.1(3), c = 1609.1(3) pm]. The calcium atom is coordinated by the four oxygen atoms of two chelating DME molecules and two nitrogen atoms of the diazadiene ligand, bonded in its enediamide form.[Ba2(DME)3(NPh–CPh=CPh–NPh)2 · DME] 3 was obtained from barium metal and NPh=CPh-CPh=NPh in DME solution as red crystals [space group monoclinic, P2l/c, Z = 4, 4000 observed unique reflections, R = 0.166; lattice dimensions at -70 °C: a = 1704.5(3), b = 1786.1(4), c = 2177.4(4) pm, β = 105.98(3)°]. The two barium atoms are bridged by two differently bonded diazadiene ligands (μ2-Ν,Ν′;μ-Ν, σ-Ν′). Additionally, one of the barium atoms is coordinated to two DME molecules and the other one to only one of the ether molecules. A further DME molecule is a constituent of the crystal lattice.

Synthese und Kristallstrukturen der 1,3,4-λ5σ4-Diazaphosphole / Syntheses and Crystal Structures of the 1,3,4-λ5σ4-Diazaphospholes

1993 ◽  
Vol 48 (6) ◽  
pp. 730-736 ◽  
Author(s):  
Gudrun Stieglitz ◽  
Bernhard Neumüller ◽  
Kurt Dehnicke
Keyword(s):  
Nitrogen Atom ◽  
Oxygen Atom ◽  
Crystal Structures ◽  
Structure Determination ◽  
Lithium Atom ◽  
Ion Pair ◽  
Space Group ◽  
X Ray ◽  
Lithium Complex ◽  
Moisture Sensitive

has been prepared by the reaction of Li(DME)[P(t-Bu)2] with benzonitrile in 1,2-dimethoxyethan solution. The compound forms violet, moisture sensitive crystals, which were characterized by an X-ray structure determination [Space group P21/n, Z = 4, 3282 observed unique reflections, R = 0.082. Lattice dimensions at -40°C: a = 851.0(5), b = 1238.0(3), c = 3029.2(4) pm, β = 90.53(4)°]. The compound forms an ion pair, in which the lithium atom is coordinated by two oxygen atoms of a chelating DME molecule, by an oxygen atom of a nonchelating DME molecule, and by the nitrogen atom of the planar diazaphosphole ring in 1-position. The phenyl groups are nearly coplanar with the diazaphosphole ring. is the product of the reaction of the lithium complex with methanol. It forms colourless crystals [Space group Ρ21/n, Ζ = 4, 2015 observed unique reflections, R = 0.068. Lattice dimensions at -80°C: a = 1458.3(2), b = 824.8(1), c = 1716.9(2) pm, β = 105.37(9)°]. The molecules have planar 5 H-diazaphosphole rings.

Preparation and X-ray crystal structures of the arsenic pentafluoride adducts of benzo-2,1,3-thiadiazole and benzo-1,2,3-thiadiazole

1986 ◽  
Vol 64 (5) ◽  
pp. 849-853 ◽  
Author(s):  
Allen Apblett ◽  
Tristram Chivers ◽  
John F. Richardson
Keyword(s):  
Nitrogen Atom ◽  
Crystal Structures ◽  
Benzene Ring ◽  
Heterocyclic Ring ◽  
Monoclinic Space Group ◽  
Crystal Data ◽  
Space Group ◽  
X Ray ◽  
X Ray Crystallography ◽  
C Nmr

The reaction of arsenic pentafluoride with benzo-2,1,3-thiadiazole, 1, or benzo-1,2,3-thiadiazole, 2, in liquid SO2 gave 1:1 adducts that were characterized spectroscopically (infrared and 13C nmr) and by X-ray crystallography. Crystal data: for 1•AsF5, monoclinic, space group P21/n, a = 6.932(1), b = 9.113(1), c = 15.136(2) Å, β = 98.035(7)°, V = 946.8(2) Å3, Z = 4; for 2•AsF5, monoclinic, space group P21/a, a = 7.573(2), b = 13.101(2), c = 9.514(3) Å, β = 90.95(2)°, V = 943.9(4) Å3, Z = 4. The coordination of AsF5 to one of the nitrogen atoms in 1 introduces asymmetry in the heterocyclic ring, with the longer bond lengths being associated with the coordinated nitrogen atom, d(S—N) = 1.633(5) and 1.577(6) Å, d(C—N) = 1.364(7) and 1.339(8) Å. The quinonoid character of the benzene ring is still apparent in the adduct. In 2•AsF5, the AsF5 molecule is coordinated to the nitrogen atom that is bonded to carbon.

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