Frank Weller

Phosphorane iminato complexes of main group elements

Abstract A review on syntheses, chemical reactions, structures and bonding of phosphorane iminato complexes of main group elements is given. The ligand group [(:N:)=PR 3 ] − is not known in the ionic state. Among others, it is isoelectronic with the ligand groups OPR 3 ,

Nitrido bridges between transition metals and main group elementsillustrated by the series [M]NNa to [M]NCl

A survey is given of the structures and bonding modes of nitrido bridges between transition metals with MN multiple bonds and main group elements. Illustrated by the period row sodium (I) to chlorine (VII) (or a homologue) along with variable transition metals M, characteristic examples are compiled, their principles of synthesis are presented and the step-by-step alterations of the bonding conditions that occur in this period are discussed on the basis of structural parameters. These bonding conditions can be divided into three groups. (1)  Electrostatic bond between nitrido ligand and main group element (I, II) (2)  Covalent single bond (III, IV) (3)  Multiple bonds between both neighbouring elements (V–VII) One example each is designed to illustrate this aim: (i) Na6[MoN4]; (ii) [Mg(THF)4{NMoCl4(THF)}2 ]; (iii) [ReN–GaCl3(PMe2Ph)(Et 2dtc)2] (no example with Al is known up to now); (iv) Cl3VN–SiMe3; (v) O3ReNPMe3; (vi) [Cl5WNSCl]−; (vii) [F5WNCl]−.

Darstellung und schwingungsspektren von trimethylzinndiorganothiophosphinaten Me3SnOSPR′R″ (R′R″ = Me2, MePh, Ph2). Die kristallstruktur von Me3SnOSPMe2

Abstract A series of trimethyltin diorganothiophosphinates Me 3 SnOSPR′R″ (R′R″ = Me 2 , MePh, Ph 2 ) was prepared from (Me 3 Sn) 2 O and R′R″PSCl in cyclohexane solution. A close study of the vibrational spectra is given; 31 P NMR and mass spectra are also reported. The structural investigation of Me 3 SnOSPMe 2 by means of X-ray diffraction ( R 5.2%, 1697 observed independent reflexions) shows the compound to consists of chains, in which planar SnMe 3 units and tetrahedral OSPMe 2 groups are linked by the O- and S-atoms of the thiophosphinate.

Carbonyl insertion into zirconium–nitrogen bonds; synthesis and X-ray structure of a carbene complex composed of [Zr(NMe2)4]2 and three Fe(CO)5 units containing Fe→Zr donor–acceptor interactions

Abstract The reaction of [Zr(NMe 2 ) 4 ] 2 with Fe(CO) 5 leads to the multicarbene complex ( 1 ) containing two zirconium and three iron atoms. The crystal structure revealed that 1 results from the insertion of five CO groups into ZrN bonds generating chelating biscarbene ligands at two iron atoms and one terminal carbene ligand at the third iron atom. Thus, a planar and a boat-configured ring are formed ( A and B ) with relatively short FeZr distances of 284 and 282 pm, respectively, indicating early–late transition-metal interactions.

Syntheses, Spectroscopic Studies, and Crystal Structures of Me2Sn(O2PPh2)2, Ph2Pb(O2PMe2)2, and Ph2Pb(O2PPh2)2

Me2Sn(O2PPh2)2 (1), Ph2Pb(O2PMe2)2 (2), and Ph2Pb(O2PPh2)2 (3) have been synthesized by the reactions of Me2SnCl2 or Ph3PbCl with the corresponding diorganophosphinic acid in methanol. X-ray diffraction studies show that the diorganophosphinate groups behave as double bridges between the metal atoms leading to polymeric ring-chain structures with M2O4P2 (M = Pb, Sn) eight-membered rings. The organic groups bonded to the metal atoms are in trans-position in the resulting octahedral arrangement around the metal atoms. The IR and the mass spectra were reported and discussed. Synthesen, spektroskopische Untersuchungen und Kristallstrukturen von Me2Sn(O2PPh2)2, Ph2Pb(O2PMe2)2 und Ph2Pb(O2PPh2)2 Me2Sn(O2PPh2)2 (1), Ph2Pb(O2PMe2)2 (2) und Ph2Pb(O2PPh2)2 (3) wurden durch Reaktion von Me2SnCl2 bzw. Ph3PbCl mit der entsprechenden Diorganophosphinsaure in Methanol dargestellt. Rontgenkristallstrukturuntersuchungen zeigen, das die Diorganophosphinatgruppen als Doppelbrucken zwischen den Metallatomen wirken und so polymere Ringkettenstrukturen mit M2O4P2 (M = Sn, Pb)-Achtringen aufbauen. Die organischen Substituenten an den Metallatomen stehen innerhalb der oktaedrischen Umgebung der Metallatome in trans-Stellung. Die IR-und Massenspektren der Verbindungen werden diskutiert.

NEt4[(η5-C5H5)Mo(CO)2Se2]; Synthese und Kristallstruktur

Abstract NEt 4 [(η 5 -C 5 H 5 )Mo(CO) 2 Se 2 ], as black crystals, has been prepared by the reaction of tetraethylammonium polyselenide with [(η 5 -C 5 H 5 )Mo(CO) 3 ] 2 in ethanol solution at room temperature. The compound was identified by an X-ray diffraction study: space group P 2 1 , Z = 2, R - 0.048 for 2970 independent, observed reflexions. The lattice constants at 18°C are: a 826.9; b 1004.7; c 1201.3 pm; β 107.88°. The compound consists of the cation, NEt 4 + , and the anions [(η 5 -C 5 H 5 )Mo(CO) 2 Se 2 ] − , in which the molybdenum atom is surrounded by a η 5 -bonded cyclopentadienyl ring, two carbonyl ligands, and the η 2 -bonded diselenide group, to give MoSe distances of 260 pm.

Über die kristallstrukturen von Me3SnO2PCl2 und Me3SnO2PMe2 und das Schwingungsspektrum von Me3SnO2PMe2

Abstract Me 3 SnO 2 PMe 2 is prepared by treatment of Me 3 SnNEt 2 with Me 2 PO 2 H in methylene chloride. The vibrational spectrum is discussed. Crystal structure determinations from X-ray diffraction data have been carried out with single crystals of Me 3 SnO 2 PMe 2 ( R 0.076, 819 observe independent reflexions), and Me 3 SnO 2 PCl 2 ( R 0.051, 1127 observed independent reflexions), showing polymer chains of SnMe 3 groups and O 2 PX 2 (X = Cl, Me) units in both cases. The phosphinate chains form vast helices whereas the dichlorophosphate forms almost planar chains.

Synthesen und Kristallstrukturen der Kronenether-Komplexe [Li3(12-Krone-4)3O2CCH3] [Cd(Se4)2], {[K(18-Krone-6)]2[Hg(Se4)2]}2 und [Na(15-Krone-5)]NO3 / Syntheses and Crystal Structures of the Crown Ether Complexes [Li3(12-Crown-4)33O2CCH3][Cd(Se4)2], {[K(18-Crown-6)]2[Hg(Se4)2]}2, and [Na(15-Crown-5)]NO3

[Li3(12-crown-4)3O2CCH3][Cd(Se4)2] has been prepared by the reaction of [Li(12-crown-4)]2Se6 with Cd(C2CCH3)2 in ethanolic solution. The corresponding polyselenide complex of mercury is formed by the reaction of [K(18-crown-6)]2Se6 with Hg(O2CCH3)2 in the same solvent. Both com pounds form dark red crystals, which were characterized by single crystal X-ray structure determinations. The only product to be isolated from the reaction of Bi(NO3)3·5H2O with [Na( 15-crown-5)]2Se6 in ethanolic solution was [Na(15-crown-5)]NO3, whose structure has also been determined. [Li3(12-crown-4)3O2CCH3][Cd(Se4)2]: space group Pbca, Z = 8. 1404 observed independent reflexions. R = 0.097. Lattice dimensions (19 °C): a = 1981.5(6). b = 1400.3( 1), c = 3268.9(9) pm. The compound forms a dicationic ensemble, in which three lithium ions coordinate with the oxygen atoms of the acetate ion. In the anions the cadmium atom is coordinated tetrahedrally by four selenium atoms of two Se42- units. {[K (18-crown-6)]2[Hg(Se4)2]}2: space group P 1, Z = 1. 3210 observed independent reflexions, r = 0.055. Lattice dimensions (19 °C): a = 1057.4(2). b = 1130.6(2), c = 2000.1(2) pm. α = 88.52(1)°, β = 85.86(1)°, γ = 66.22(1)°. The com pound has a complex ionic structure, in which the formula units form centrosymmetric dimers through K-O contacts between two cations. In addition there are K···Se contacts with the spiro-bicyclic anions, which - together with 6 K-O bonds within the crowns - lead to the coordination number of 8 for the remaining potassium ions. [Na(15-crown-5)]NO3: space group P212121, Z = 4. 1211 observed independent reflexions. R = 0.052. Lattice dimensions (20 °C): a = 912.9(2). b = 989.6(1). c = 1658.3(3) pm. The compound forms ion pairs, in which the sodium atom coordinates with the five oxygen atoms oi the crown ether, as well as with two oxygen atoms of the nitrate ion with Na -O bond lengths of 240 and 247 pm.

[Mo2(O2C–CH3)4 · 1/2 {(CH2)6N4} · 1/2 CH2Cl2] – ein Donor‐Akzeptor‐Komplex mit supramolekularer Struktur

[Mo2(O2C–CH3)4 · 1/2 {(CH2)6N4} · 1/2 CH2Cl2] – a Donor-Acceptor Complex with Supramolecular Structure Yellow single crystals of [Mo2(O2C–CH3)4 · 1/2 {(CH2)6N4} · 1/2 CH2Cl2] (1) have been obtained by the reaction of the silylated phosphaneimine Me3SiNPEt3 with [Mo2(O2C–CH3)4] in dichloromethane solution. 1 forms a three-dimensional network with linear N–Mo:Mo–N and tetrahedral (CH2)6N4Mo4 moieties, which is topologically related with the PtS type. Space group P42/nnm, Z = 4, lattice dimensions at –70 °C: a = b = 1121.7(1), c = 1395.0(3) pm, R1 = 0.0413.

REACTION OF 1,1,3,3-TETRAKIS(DIMETHYLAMINO)-1λ5,3λ5-DIPHOSPHETE, 1, WITH CARBONDISULFIDE II. DIHYDRO-λ5-PHOSPHETES; NMR ISOTOPE EFFECTS

Abstract 1,1,3,3-Tetrakis(dimethylamino)-1-phospha-3-phosphonium-2-dithio-carboxylato-cyclobutene-1, 2,1 is thermally unstable. By heating it is converted quantitatively into [1,1-bis(dimethylamino)-3-thioxo-3,4-dihydro-1λ5-phosphete-2-yl]-phosphonothioic bis(dimethylamide), 3. Reaction of the 2,4-dimethylderivative of the title compound 1, i.e. 4, with CS2 yields [1,1-bis(dimethylamino)-2,4-dimethyl-3-thioxo-2,3-dihydro-1λ5-phosphete-2-yl]-phosphonothioic bis(dimethylamide) 7. The new compounds are characterized by their properties and their nmr, it and mass spectra. Isotope effects on δ31P of 7 are described. The results of the X-ray structural analyses of 3 and 7 are reported and discussed.