| 1 | Author
| Günter Schmid, Roland Boese | Requires cookie* | | Title
| Azaborolinyl Complexes, IX [1] The Crystal and Molecular Structures of Two Isomers of Bis(l-ter£-butyl-2-methyl-??-l,2-azaborolinyl)cobalt  | | | Abstract
| The crystal and molecular structures of two isomers of bis(l-£er£-butyl-2-methyl-??-l,2-azaborolinyl)cobalt have been determined by single-crystal X-ray diffraction methods. Isomer 1 shows a clockwise, isomer 2 an anti-clockwise conformation of the azaborolinyl rings. In both compounds the azaborolinyl rings have staggered orientations with opposite positions of the tferi-butyl groups. The rings in 1 and 2 are slipped so that the three ring carbon atoms are closer to the cobalt atom than the BN groups. The staggered orientation of the ligands in 2 is probably due to a packing effect, as in similar sandwich complexes the anti-clockwise conformers show eclipsed orientation. | | |
Reference
| Z. Naturforsch. 38b, 485—492 (1983); eingegangen am 12. November 1982 | | |
Published
| 1983 | | |
Keywords
| Azaborolinyl Sandwich Complexes, Cobalt, Isomers, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-0485.pdf | | | Identifier
| ZNB-1983-38b-0485 | | | Volume
| 38 | |
3 | Author
| Werner Winter, Reinhard Merkel, Udo Kunze | Requires cookie* | | Title
| Koordinationschemie funktioneller Phosphorylide, V [1] Die Molekülstrukturen der isomorphen Mangan-und Rheniumbromtricarbonyl- komplexe von 2-Methyl-2-(triphenylphosphonio)dithiopropionat Coordination Chemistry of Functional Phosphorus Ylides, V [1] The Molecular Structures of the Isomorphous Manganese and Rhenium Bromotricarbonyl Complexes of 2-Methyl-2-(triphenylphosphonio)dithiopropionate  | | | Abstract
| The isomorphous crystal structures of the manganese and rhenium bromotricarbonyl complexes 2 a, b have been determined at room temperature (Mn) and at —110 °C (Mn, Re; P2x/c, Z — 4). At room temperature, data collection is accompanied by crystal decomposi-tion, and a cleavage of the PPh3 group is suggested by the results as the primary process. The same initial step is thought to be valid for the photodecomposition in solution. The main structural difference between the free and coordinated betaine ligand 1 is the reduced electrostatic interaction of P and S in the complexed form. Einführung | | |
Reference
| Z. Naturforsch. 38b, 747—751 (1983); eingegangen am 20. März 1983 | | |
Published
| 1983 | | |
Keywords
| Manganese, Rhenium, Betaine Complexes, Dithiocarboxylate Complexes, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-0747.pdf | | | Identifier
| ZNB-1983-38b-0747 | | | Volume
| 38 | |
4 | Author
| Klaus Brodersen, Hans-U Hummel | Requires cookie* | | Title
| Die Kristallstrukturell von CaHg(SCN)4 * /ili20 (n = 2,3). Verwandtschaftsbeziehungen zwischen den Verbindungsklassen der Tetrathiocyanatomercurate(II) von Erdalkaliionen und 3 d-Metallionen The Crystal Structures of CaHg(SCN)4 * MH20 (n = 2, 3). Relations between Tetrathiocyanatomercurates(II) of the Alkaline-Earth-Ions and Ions of the 3 d-Type  | | | Abstract
| CaHg(SCN)4 • nH20 (n — 2(1), n = 3(2)) were isolated from an aqueous solution of Ca(NCS)2 • 4H20 and Hg(SCN)2. 1 is compared with the analogous MgHg(SCN)4 • 2H20 by means of powder patterns. The crystal structure of 2 has been determined. 2 is mono-clinic, space group P2i/c with a = 9.469(4), 6 = 22.781(5), c = 6.587(4) A, 0 = 93.6(3)°, Z = 4, dc = 2.46 g-cm -3 . The structure was refined to .ß=7.42 and i?w = 4.96% for 1224 independent reflec-tions. The species MHg(SCN)4 • 2H20 (M = Mg, Ca, Ni) contain nearly tetrahedral Hg(SCN)4 and octahedral M(OH2)2(NCS)4 groups which are joined by Hg-SCN-M bridges. In contrast the structures of the other compounds MHg(SCN)4 • nH20 (M = Co, n = 0; M = Ca, Sr, n = 3) are based on the diamond net. There is tetrahedral coordination of all the metal atoms, M having 4 N and Hg 4 S nearest neighbours. In the hydrates the H20 molecules are situated additionally at the Ca and Sr atoms [*]. | | |
Reference
| Z. Naturforsch. 38b, 911—916 (1983); eingegangen am 20. April 1983 | | |
Published
| 1983 | | |
Keywords
| Calciumtetrathiocyanatomercurates(II), Dihydrate, Trihydrate, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-0911.pdf | | | Identifier
| ZNB-1983-38b-0911 | | | Volume
| 38 | |
5 | Author
| KurtH. Pilgram, LairdH. Gale, GlennE. Pollard | Requires cookie* | | Title
| a-hydroxyphostones  | | | Abstract
| The addition-cyclocondensation reactions of three /?-hydroxyketones with four dialkyl phosphites gave 2-alkoxy-3-hydroxy-l,2-oxaphospholane-2-oxides ("a-hydroxyphosto-nes") (7), in moderate yields. In the solid state and in solution, these compounds exist as dimers with hydrogen bonding between the hydroxyl group and the phosphoryl oxygen atom of an adjacent molecule. The crystal and molecular structure of 3-hydroxy-2-methoxy-3,5,5-trimethyl-l,2-oxaphospholane-2-oxide (7 a) has been determined by single-crystal X-ray crystallography: C7H15O4P, monoclinic space group P2-l/n, cell dimensions a = 8.087(1) Ä, b = 13.386(2) A, c = 9.306(1) A, V = 1007.4 Ä 3 , Z = 4, final R = 0.052. The five-membered ring is puckered, with the carbon bearing the OH and CH3 groups lying out of the plane of the remaining four atoms in the ring. The doubly bonded oxygen attached to the phosphorus atom and the hydroxyl oxygen are in a cis-relationship. The 0(l)-0(4) intermolecular bond distance of 2.75 Ä suggests hydrogen bonding. The 0(1)-H(1) intermolecular bond distance of 1.97 Ä is consistent with this conclusion. Thorough synthetic studies have been carried out on intramolecular esters of 3-hydroxyalkane (and alkene) phosphonic and phosphinic acids (phosto-nes [1]). For example, dehydration of 3-hydroxy-alkanephosphonic acids gave phostones of general structure 1 [2] (Table I). Similar phostones, 2 and 3, were obtained from the reactions of 1,3-dihalo-alkanes with phosphonites and phosphinites, re-spectively [3]. At elevated temperature, 3-bromo-alkanephosphonates are converted into phostones 4 [4]. Acyl-lactone rearrangement of a-acetyl-a-diethoxyphosphonylbutyrolactone gave 5 [5]. Unsaturated phostones (8) are obtained by dehydration of the corresponding (3-hydroxy-3-phenyl-prop-2-enyl)phosphonic acids [6]. 3-Hy-droxypropenylphosphonates, prepared by catalytic reduction of 3-hydroxy-l-propynyl-phosphonates, cyclocondense to 9 having potent Cholinesterase inhibitory activity [7]. The reaction of dialkyl 1,2-alkadienylphosphonates with halogens [8-10] and sulfenyl chlorides [12] gave 10. In the reaction of 3-methyl-l,2-butadienephos-phonyl di chloride with halogens, unsaturated tetra-halophostones (11), are formed [13]. The chlorina-tion of 2-methyl-2,3,5-hexatriene-4-phosphonyl di-chloride proceeds similarly in the direction of cyclo-dechlorination to form 12 [14]. | | |
Reference
| Z. Naturforsch. 38b, 1122—1129 (1983); received May 6 1983 | | |
Published
| 1983 | | |
Keywords
| X-Ray, Stereochemistry, Hydrogen Bonding, Dimerization | | |
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| default:Reihe_B/38/ZNB-1983-38b-1122.pdf | | | Identifier
| ZNB-1983-38b-1122 | | | Volume
| 38 | |
6 | Author
| Matthias Moll, Behrens* Werner Helmut, Günther Popp, WolfPeter Liehr, Fehlhammer | Requires cookie* | | Title
| Über das [C7H7Fe2(CO)5]--Anion (C7H7 = Cycloheptatrienyl) About the [C7H7Fe2(CO)5]--Anion (C7H7 = Cycloheptatrienyl)  | | | Abstract
| The extremely unstable anionic complex [C7H7Fe2(CO)6]~ (C7H7 = cycloheptatrienyl) which decomposes in polar solvents under CO elimination to give [C7H7Fe2(CO)s]~ can be prepared by deprotonation of C7H8Fe2(CO)6 (C7H8 = cycloheptatriene) with NaN(SiMe3)2 in CßHe-The NMR spectra of [C7H7Fe2(CO)5]~ show the highly fluctional character of this anion in solution. The X-ray structural parameters of Ph4As[C7H7Fe2(CO)5] (space group P2i/n) can be interpreted in terms of a rotation of the tub shaped C7H7 ring against the CO bridged Fe2(CO)5 fragment in the solid state. Consequently, each iron atom is alternatingly rj 3 -or ^-coordinated to the allyl anion and the diene part, respectively, of the anionic 8n system of the cycloheptatrienyl ring. | | |
Reference
| Z. Naturforsch. 38b, 1446—1453 (1983); eingegangen am 7. Juni 1983 | | |
Published
| 1983 | | |
Keywords
| Cycloheptatrienyl Pentacarbonyl Diferrate, IR Spectra, NMR Spectra, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-1446.pdf | | | Identifier
| ZNB-1983-38b-1446 | | | Volume
| 38 | |
7 | Author
| Ulrich Schubert, Klaus Ackermann, Gertraud Kraft, Barbara Wörle | Requires cookie* | | Title
| Hydrido-Silyl-Komplexe, IV [1] Strukturelle Änderungen in Hydrido-Silyl-Komplexen  | | | Abstract
| infolge Si-H-Wechselwirkung; Strukturvergleich von (^CH3C5H4)(CO)2Mn(H)SiCl3 und trans-(n-CH3C5H4)(CO)2Mn(SiCl3)2 Hydrido Silyl Complexes, IV [1] Structural Changes in Hydrido Silyl Complexes Due to Si-H Interaction; Comparison of the Structures of (7t-CH3CöH4)(CO)2Mn(H)SiCl3 and *ra7is-(7r-CH3C5H4)(CO)2Mn(SiCl3)2 The main difference between the structures of MeCp(CO)2Mn(H)SiCl3 (1) and MeCp(CO)2Mn(SiCl3)2 (2) is that in 1 the SiCl3 ligand is tilted relative to the Mn-Si vector, due to Mn-H-Si three-center two-electron bonding. Mn-Si: 225.4(1) in 1, 232.0(2) pm in 2. Comparison of the structures of MeCp(CO)2Mn(H)SiR3 complexes shows that the Mn-Si distance and the tilt angle of the SiR3 group increases as Si-H interaction increases. A stereochemical pathway of the oxidative addition of HSiR3 to the CpMn(CO)3 fragment is suggested. | | |
Reference
| Z. Naturforsch. 38b, 1488—1492 (1983); eingegangen am 17. Mai 1983 | | |
Published
| 1983 | | |
Keywords
| Silyl Metal Complexes, Three-Center Bonding, Si-H Interaction, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-1488.pdf | | | Identifier
| ZNB-1983-38b-1488 | | | Volume
| 38 | |
8 | Author
| Thomas Mack, Karl Peters, Hans-Georg Von Schnering | Requires cookie* | | Title
| Zur Stereochemie von Diazadien-Metall-Komplexen, V [1] Molekülstrukturen und CO-Kraftkonstanten nicht-starrer Chrom-, Molybdän- und Wolframcarbonylderivate DAD M(CO)3(*CO) (*C0 = 12 C0, 13 C0, C 18 0) Stereochemistry of Diazadiene Metal Complexes, V [lj Molecular Structures and CO Force Constants of Non-Rigid Chromium, Molybdenum and Tungsten Carbonyl Derivatives DAD M(CO)3(*CO) (*C0 = 12 CO, 13 C0, C 18 0) Heindirk torn Dieck  | | | Abstract
| Diazadiene metal tetracarbonyls, DAD M(CO)4, (M = Cr, Mo, W; DAD = R-N = CH-CH = NR with aliphatic and aromatic substituents R) show equi-distribution of one labelled CO when synthesized from fac-DAD M(CO)3(CH3CN) as a consequence of intramolecular CO site exchange. The structures of two Mo-complexes (1: R = iso-propyl; 2: R = 2,6-diisopropylphenyl) with DAD's of different bulkiness have been solved by X-ray methods. From the infrared solution spectra, including those of isotopically labelled (13 CO, C 18 0) compounds, all of the force constants ki, k2, ktt, kcc and kct bave been calculated independently. The ratios of interaction force constants deviate sharply from Cotton-Kraihanzel assumptions, perhaps because of the substantial deviation of the iraws-pair of CO groups from linearity (1: 154.5°, 2: 147.9°). The solid state N-Mo, Mo-C and C-0 bond lengths are neither in agreement with the generally accepted picture for donor/acceptor influences nor with typical IR data and force constant interpretations. (2 with higher v(CO) and ki, k2 has the longer CO bonds and shorter Mo-C bonds than 1.) The force constant sets have been used to calculate CO frequencies for over 60 labelled compounds with good accuracy (Av < 2 cm -1). | | |
Reference
| Z. Naturforsch. 38b, 568—579 (1983); eingegangen am 3. Dezember 1982 | | |
Published
| 1983 | | |
Keywords
| Diazadiene Chromium, Molybdenum and Tungsten Carbonyls, X-Ray, Isotopically Labelled Carbonyls | | |
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| default:Reihe_B/38/ZNB-1983-38b-0568.pdf | | | Identifier
| ZNB-1983-38b-0568 | | | Volume
| 38 | |
9 | Author
| M. Veith, 0. Reckten | Requires cookie* | | Title
| Cyclische Diazastannylene, XVIII [1] Zur Frage der Bindungsbeschreibung in Polyedern des Typs Sn4X3Y: Die Kristall-und Molekülstrukturen von Sn4(N Bu)4 und Sn4(N'Bu)30 Cyclic Diazastannylenes, XVIII [1] Bonding Description in Polyhedra of the Sn4X3Y-Type: The Crystal and Molecular Structures of Sn4(N'Bu)4 and Sn4(N<Bu)30  | | | Abstract
| Crystals of Sn4(N J Bu)4 (1) are monoclinic, space group P2i/c, with cell constants a = 1038.9(4), b = 1468.3(5), c = 1698.8(5) pm, ß = 91.6(1)° and Z = 4, while those of Sn4(N i Bu)30 (2) are triclinic, space group P I, with dimensions a = 1293.0(5), b = 1027.1(5), c = 1716.7(9) pm, a = 90.9(1), ß = 102.5(1), y = 107.0(1)° and Z = 4. The molecules 1 are held together by van-der-Waals forces, whereas two molecules 2 interact in the crystal by weak 0->-Sn donor bonds (290-332 pm) forming dimers. The outstanding structural elements of 1 and 2 are the Sn4N4 and Sn4N30 polyhedra, which can be described by two interpenetrating tetrahedra of tin atoms and of nitrogen or nitrogen and oxygen atoms forming a distorted cube, which approaches "43 m symmetry in the case of 1 and 3m for 2. Characteristic distances are in 1: Sn-N 220.2 pm, in 2: Sn-N 221.3 pm and Sn-0 213.2 pm. An almost ionic bonding model and two covalent models are discussed on the basis of the structural data including Sn4(N i Bu)3OAlMe3. | | |
Reference
| Z. Naturforsch. 38b, 1054—1061 (1983); eingegangen am 9. Juni 1983 | | |
Published
| 1983 | | |
Keywords
| gewidmet Crystal Structure, Molecular Structure, Cubane-Like Polycycles, Bonding Description, X-Ray | | |
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| default:Reihe_B/38/ZNB-1983-38b-1054.pdf | | | Identifier
| ZNB-1983-38b-1054 | | | Volume
| 38 | |
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