Jörg Magull

Preparation of Ti(IV) fluoride N-heterocyclic carbene complexes.

1,3,4,5-Tetramethylimidazol-2-ylidene (L(Me)) and 1,3-diisopropyl-4,5-dimethylimidazol-2-ylidene (L(iPr )) readily form complexes of trans-TiF4(L(Me))2 (1) and of trans-TiF4(L(iPr))2 (4) with TiF4 in THF, respectively. Complex 1 has been used as a precursor for preparing the Ti(IV) fluoride carbene complexes [{TiF2(L(Me))(NEt 2)}2(mu-F)2] (2) and (TiF4(L(Me))2)(NacNacLi) (3) (NacNac = HC(CMeN(2,6- iPr2C6H3))2). Complex 2 was prepared from the reaction of 1-3 equiv of 1 and 1 equiv of Ti(NEt2)4 or by reacting TiF4 with Ti(NEt2)4 and L(Me) in toluene. Complex 3 has been prepared from 1 and NacNacLi in toluene. Reaction of 1 and AlMe3 in toluene results in ligand transfer and formation of AlMe3(L(Me)). Complex 4 is unstable in solution at room temperature and degrades with formation of [HL(iPr)][TiF5(L(iPr))] (5). Complexes 1, 2.2CH2Cl2, 4, and 5 were characterized by single crystal X-ray structural analysis, elemental analysis, IR and NMR spectroscopy, and mass spectrometry. The relative basicities of L(Me), L (iPr), and the donor ligands THF, pyridine, DMSO, and H2O as well as [Cl](-) and [F](-) toward the Ti(IV) pentafluoride anion were established by NMR and confirmed by density functional theory (DFT) calculations. L(Me) and L(iPr ) are more basic than the mentioned molecular donors and more basic than chloride, however less basic than fluoride.

Preparation and characterization of (C5Me4Ph) TiCl3, the oxochloride complexes [(C5Me4Ph) TiCl2]2(μ-O) and [(C5Me4Ph)TiCl(μ-O)]3 and the oxo-complex[(C5Me4Ph)Ti]4(μ-O)6. The X-ray crystal structures of [(C5Me4Ph)TiCl2]2(μ-O) and [(C5Me4Ph)Ti]4(μ-O)6

Abstract The titanium compound (C5Me4Ph)TiCl3 (1) can be prepared by the reaction of (C5Me4Ph)SiMe3 with TiCl4. Hydrolysis of 1 in the presence of HNEt2 or Ag2O has allowed for the isolation of the oxochloride complexes [(C5Me4Ph)TiCl2]2(μ-O) (2) and [(C5Me4Ph)TiCl(μ-O)]3 (3), respectively. The NMR spectra of 3 are consistent with a nearly flat Ti3O3 ring having down—up—up or E-Z-Z arrangement of (C5Me4Ph)-ligands around the ring. The X-ray crystal structure of 2 (monoclinic, space group C2/c, a = 19.847(12), b = 9.089(5), c = 20.405(13)A, β = 124.06(5)°) consists of trans[(C5Me4Ph)TiCl2]2(μ-O) molecules of C2 symmetry with nearly linear Ti-O-Ti units (169.3(2)°). Reaction of 1 with an excess of H2O/HNEt2 results in the formation of the cxo-complex [(C5Me4Ph)Ti]4(μ-O)6 (4). The X-ray crystal structure of 4 (triclinic, space group P1¯, a = 11.861(5), b = 12.706(5), c = 18.218(8)A, α = 87.58(3)°, β = 89.00(3)°, γ = 86.60(3)°) reveals that the molecules of 4 have an adamantane-like Ti4O6 cage of nearly Td symmetry. The NMR spectra and molecular structures of 1, 2, 3 and 4 are discussed.

The reaction of P4 with [Cp′Mo(CO)3]2 (Cp′ = η5-C5H4tBu)—the structure of [Cp′Mo(CO)2 ]

Abstract The photochemical reaction of [Cp′Mo(CO)3]2 (Cp′ = η5-C5H4tBu) with white phosphorus in the presence of [Cr(CO)5thf] leads to the Pn ligand complexes [Cr(CO)4 ;] (1), [Cp′Mo(CO)2 ] (2) and [{Cp′Mo(CO)2}2 ] (3). The products were characterized by NMR, IR and partially by X-ray structure analysis. The reaction proceeds via a Pue5f8P bond cleavage leading to the bent cyclo-P4 complex [Cp′Mo(CO)2 ] (2a), which hydrolysis during the chromatographic work-up to give the more stable compound 2. Furthermore, a P 3 P 1 fragmentation of 2a occurs to form the phosphido complex intermediate [CP′CO)2Moue5f8P → Cr(CO)5]. The latter dimerises resulting in the formation of the tetrahedral compound 3, containing a Mo2P2 moiety.

Die Kristallstrukturen der Dysprosium-Komplexe [DyCl3(DME)2] und [DyCl2(THF)5]+[DyCl4(THF)2]- / Crystal Structures of the Dysprosium Complexes [DyCl3(DME)2] and [DyCl2(THF)5]+[DyCl4(THF)2]-

Abstract [DyCl3(DME)2] (DME = 1,2-dimethoxyethane) has been prepared from the known tetrahy-drofuran complex [Dy2Cl6(THF)7] in boiling DME. Both complexes were characterized by structure determinations. [DyCl3(DME)2]: Space group P21/c, Z = 4, lattice dimensions at -70 °C: a = 1141.9(6), b = 884.2(4), c = 1558.3(6) pm, β = 104.83(4)°. The complex has a molecular structure with a distorted pentagonal bipyramidal geometry in which the oxygen atoms of the chelating DME molecules and one chlorine atom occupy the pentagonal plane. [DyCl2(THF)5]+[DyCl4(THF)2]-: Space group C2/c, Z = 4, lattice dimensions at -70 °C: a -1241.4(9), b = 1139.4(6), c = 2735.1(19) pm, β = 91.19(4)°. The complex contains a seven-coordinate cation with axial chloride ligands in a pentagonal bipyramidal structure and a six-coordinate anion with a trans octahedral geometry.

Phosphaniminato‐Komplexe von Rhenium(VII). Synthesen und Kristallstrukturen von [ReO3(NPR3)] (R = Ph, Et) sowie von [ReO(OSiMe3)3(Me3SiNPEt3)]

Die Phosphaniminato-Komplexe [ReO3(NPR3)] mit Ru200a=u200aPh (1) und Ru200a=u200aEt (2) werden aus Dirheniumheptoxid und den silylierten Phosphaniminen Me3SiNPR3 hergestellt und ebenso wie das bei der Synthese von 2 als Nebenprodukt gebildete rote Silanolat [ReO(OSiMe3)3(Me3SiNPEt3)] (3) kristallographisch charakterisiert. 1 und 2 sind monomere Molekule, in denen die Phosphaniminato-Liganden NPR3– kurze ReN-Bindungen von 179,3u200apm (1) bzw. 178,6u200apm (2) realisieren bei grosen ReNP-Bindungswinkeln von 162,0° (1) bzw. 160,6° (2). In dem Rhenium(V)-Komplex 3 besetzt der Oxoligand die apicale Position der tetragonal-pyramidalen Koordination des Rheniumatoms, wahrend die O-Atome der OSiMe3–-Gruppen zusammen mit dem N-Atom des Phosphanimin-Molekuls die Basispositionen einnehmen. n n n nPhosphoraneiminato Complexes of Rhenium(VII). Syntheses and Crystal Structures of [ReO3(NPR3)] (Ru200a=u200aPh, Et) and of [ReO(OSiMe3)3(Me3SiNPEt3)] n n n nThe phosphoraneiminato complexesxa0[ReO3(NPR3)] with Ru200a=u200aPh (1) and Ru200a=u200aEt (2) are made from dirhenium heptaoxide and the silylated phosphoraneimines Me3SiNPR3. The complexes 1 and 2 as well as the red silanolate [ReO(OSiMe3)3(Me3SiNPEt3)] (3), which is formed as a by-product in the synthesis of 2, are characterized crystallographically. 1 and 2 are monomeric molecules, in which the phosphoraneiminato ligands NPR3– realize short ReN bonds of 179.3u200apm (1) and 178.6u200apm (2), respectively, with large ReNP bond angles of 162.0° (1) and 160.6° (2), respectively. In the rhenium(V) complexu200a3 the oxoligand occupies the apical position of the tetragonal pyramidal coordination of the rhenium atom, while the oxygen atoms of the Me3SiO– groups take the basic positions along with the nitrogen atom of the phosphaneimine molecule.

Phosphanimin- und Phosphaniminato-Komplexe des Zinks. Kristallstrukturen von [ZnCl2(Me3SiNP(CH2)4CMe3)]2, [ZnI2(Me3SiNPEt3)]2, [ZnI2{Me2Si(NPEt3)2}] und [ZnBr(NPMe3)]4· CH2Cl2/ Phosphaneimine and Phosphoraneiminato Complexes of Zinc. Crystal Structures of [ZnCl2(Me3SiNP(CH2)4CMe3)]2, [ZnI2(Me3SiNPEt3)]2, [Znl2{Me2Si(NPEt3)2}], and [ZnBr(NPMe3)]4· CH2Cl2

Abstract The donor-acceptor complexes [ZnCl2(Me3SiNP(CH2)4CMe3)]2 (1)and [ZnI2(Me3SiNPEt3)]2 (2) have been prepared from the zinc dihalides and the corresponding silylated phosphaneimines in CH2Cl2. Thermolysis of 2 leads to the formation of [ZnI2(Me2Si(NPEt3)2)] (3). Znl2 and ZnBr2 react with the silylated phosphaneimines Me3SiNPR3(R = Me, Et) in the presence of NaF at elavated temperatures to give the phosphoraneiminato complexes [ZnI(NPEt3)]4 (4), [ZnBr(NPMe3)]4 (5) and [ZnBr(NPEt3)]4 (6), respectively, which according to the IR spectra and to a crystal structure determination of 5 form heterocubane structures. The corresponding reactions with the more bulky phosphaneimine Me3SiNP(CH2)4CMe3 do not lead to a phosphoraneiminato complex of zinc. 1: Space group P21/n, Z = 2; lattice dimensions at -60 °C: a = 903.3(2), b = 1217.9(3), c = 1591.6(2) pm, β = 93.94(1)°, R = 0.031. 2: Space group P21/n, Z = 2; lattice dimensions at -70°C: a = 947.9(2), b = 1219.2(2), c - 1527.1(2) pm, 0 = 91.17(1)°, β = 0.045. 1 and 2 form centrosymmetric dimeric molecules via Zn2X2 bridges (X = Cl, I); bond lengths Zn-N = 198.7(2) pm (1) and 199.0(6) pm (2). 3: Space group P412121 Z = 8; lattice dimensions at -90°C: a = b = 965.4(1), c = 2796.9(2) pm, R = 0.019.3 forms monomeric molecules with the Me2Si(NPEt3)2 ligand as chelating agent to give a planar ZnN2Si four-membered ring with Zn-N distances of 207.0(2) pm. 5: Space group P42/nmc, Z = 2; lattice dimensions at -70°C: a = b = 1146.9(6), c = 1437.9(7) pm, R = 0.060.

N,N′-Bis(silyl)ethylendiamine und 1,3-Diaza-2-silacyclopentane – Synthese, Reaktionen, Strukturen/ N,N′-Bis(silyl)ethylenediamines and 1.3-Diaza-2-silacyclopentanes – Synthesis, Reactions, Crystal Structures

Ethylenediamine reacts with chlorosilanes to give N,N′-bis(silyl)ethylenediamines [(H2CNHSiRR′R″)2, 3: R, R′ = Me; R″ = CMe3; 4: R = H; R′, R″= CMe3; 5: R,R′ = CMe3, R″ = OH]. In the reaction of N,N,N′-tris(trimethylsilyl)ethylenediamine with SiF4 the difluoro-bis(1.1.4- tris(trimethylsilyl)ethylenediamino)silane (6) is obtained. The 1.3-diaza-2-silacyclopentanes R2Si[N(SiMe2R′)CH2]2, 7 - 10 (7: R = Cl, R′= Ph; 8: R = Cl, R′ = CMe3; 9: R = H, Cl, R′ = CMe3; 10: R = Br, R′ = CMe3) are isolated from the reactions of the corresponding bis(silyl)ethylenediamines and halosilanes in Et2O with NEt3 as HHal acceptor. Dilithium derivatives of N,N′-bis(silyl)ethylenediamines react with fluorosilanes with formation of the 1.3-diaza-2-silacyclopentanes, R2Si[N(SiMe2R′)CH2]2 (11 - 13) (11: R = F,R′ =Me; 12: R = F, R′ = CMe3; 13: R = CHMe2, R′ = Me). N-Fluoro-di(tert-butyl)silyl-N,N′-bis(trimethylsilyl)- ethylenediamine (14) is formed in the reaction of lithiated bis(trimethylsilyl)ethylenediamine with F2Si(CMe3)2. 8 reacts in amolar ratio 1:2 withNaNH2 or NaOMe with formation of 15 and 16, respectively · R2Si[N(SiMe2CMe3)CH2]2, 15: R = NH2; 16: R = OMe]. 1.3-Bis(tert-butyldimethylsilyl)- 2-tert-butyldimethylsiloxy-2-fluoro-1.3-diaza-2-silacyclopentane is the product of the reaction of 12 with LiOSiMe2CMe3. The crystal structures of 6 and 13 have been determined.

Synthese und Kristallstruktur von [TeCl2(NPMe3)2]2/ Synthesis and Crystal Structure of [TeCl2(NPMe3)2]2

[TeCl2(NPMe3)2]2 has been prepared by the reaction of TeCl4 with Me3SiNPMe3 in acetonitrile solution. Tlie compound forms white moisture sensitive crystals which have been characterized by IR spectroscopy and by a crystal structure determination. Space group P21/c, Z = 2, structure solution with 3510 independent reflections, R = 0.029. Lattice dimensions at - 70 °C; a = 1206.0(9); b = 1054.7(7); c = 1156.0(6) pm; β = 99.27(5)°. [TeCl2(NPMe3)2]2 forms centrosymmetric molecules via TeCl2Te bridges with bond lengths Te-Cl of 267.2 and 366.9 pm, the longer one being in trans-position to one of the terminally bounded (NPMe3-) groups. The TeN bond lengths of 190.1 and 192.6 pm are unusually short.

μ2-Chlorokomplexe von Succinimid und N-Chlorsuccinimid. Die Kristallstrukturen von PPh4[Cl(Succinimid)2], PPh4[[Cl(N-Cl-Succinimid)2] und N-Chlorphthalimid / μ2-Chloro Complexes of Succinimide and N-Chlorosuccinimide. The Crystal Structures of PPh4[Cl(Succinimide)2], PPh4[Cl(N-Cl-Succinimide)2] and N-Chlorophthalimide

Abstract The donor-acceptor complexes PPh4[Cl(succinimide)2] and PPh4[Cl(N-chlorosuccinimide)2] have been prepared by reactions of PPh4Cl with succinimide and N-chlorosuccinimide, re spectively. in acetonitrile solutions. The complexes have been characterized by IR spectros copy and by crystal structure determinations. The crystal structure of N-chlorophthalimide has also been solved.

Acyclic and Cyclic Silylaminohydrazines

The reaction of H2N-NH2 with ClSiMe2N(SiMe3)2 in a molar ratio 1 : 2 gave the bis(silylamino) hydrazine [HNSiMe2-N(SiMe3)2]2 (1). Compound 1 forms a monomeric dilithium salt with BuLi. From n-hexane (Me3Si-NSiMe2-NLiSiMe3)2 (2) crystallizes while from THF [Me3Si-NSiMe2- NLi(THF)SiMe3]2 (3) precipitates. Compounds 2 and 3 are formed from 1 via a silyl group migration. In the rearranged salts, the silyl groups are bonded at the hydrazino nitrogen atoms. Hydrolysis of 2 led to the formation of (Me3Si-N-SiMe2-NHSiMe3)2 (4) which is a structural isomer of 1. Ring closure occurs in reactions of 2 or 3 with F3B ・ OEt2 or SiF4. The seven-membered rings (Me3Si- N-SiMe2-NSiMe3)2BF (5) and (Me3Si-NSiMe2-NSiMe3)2SiF2, (6) were isolated as the products. The crystal structures of 2, 3 and 5 have been determined. Graphical Abstract Acyclic and Cyclic Silylaminohydrazines