Synthesis and infrared studies of tri- and diorganotin(IV) derivatives of benzilic acid

Some triorganotin benzilates, R₃SnB (R = CH₃, C₂H₅, C₃H₇ and C₆H₅, B = (C₆H₅)₂C(OH)COO⁻) and diorganotin dibenzilates, R₂SnB₂ (R = CH₃, C₂H₅ and n-C₄H₉) have been synthesized and characterized by elemental analysis and i.r. spectra. The i.r. data indicate that the triorganotin benzilates are tetracoordinated monomers in the solid state thus suggesting that the steric hindrance between the benzilate ion and the organotin moiety is sufficient to prevent formation of polymers. The diorganotin dibenzilates on the other hand have a cis-R₂SnCl₂ or distorted octahedral structure.     

Étude de l'oxydation de triphénylamines par voltammétrie à variation linéaire de tension en couche mince

The mechanism of the oxidation of substituted triphenylamines R₁R₂R₃N (R₂=R₃=C₆H₅, R₁=p-OCH₃C₆H₄ (1) or p-CH₃C₆H₄ (2); R₁=R₂=R₃=p-OCH₃C₆H₄ (3) or C₆H₅ (4)) has been investigated by using thin layer linear potential sweep voltammetry. The tetraphenylbenzidine which is formed during the oxidation results from a dimerization of two cation radicals. The rate constants are calculated for (1) and (2).     

Some novel triorganotin(IV) derivatives of β, δ-triketones

Thirty triorganotin(IV) derivatives of the type R₃Sn(R′COCHCOCH₂COR″) and [R₃Sn]₂ (R′COCHCOCHCOR″) (where R = CH₃, C₂H₅, nC₃H₇, nC₄H₉ and C₆H₅ and R′ = R″ = CH₃, C₆H₅ or R′ = C₆H₅, R″ = CH₃) have been synthesised by the interaction of R₃SnCl with mono- or disodium salt of 2, 4, 6-heptanetrione, 1-phenyl-1, 3, 5-hexanetrione and 1, 5-diphenyl-1, 3, 5-pentanetrione in 1:1 and 2:1 molar ratios, respectively. The complexes have been examined by their molecular weight, IR, PMR and elemental analyses and their tentative structures assigned. Both “Z” and “E” forms have been identified in the 1:1 complexes in equilibrium with the enol form containing five coordinate tin. The 2:1 derivatives contain one five- and other four coordinated tin(IV) except the phenyl analogue where both the tins are five coordinated.     

Synthesis and crystal structures of novel lithium- and palladium-1-azaallyls

Treatment of (RH₂C)₂C₅H₃N-2,6 (R=SiMe₃) with BuⁿLi followed by addition of Me₃SiCl gave the tetrasilyl pyridine derivative (R₂HC)₂C₅H₃N-2,6 1 in high yield. Further lithiation of 1 with BuⁿLi and reaction of the intermediate with PhCN led to the new lithium-1-azaallyl [Li{N(R)C(Ph)C(R)(C₅H₃N-2,6)(CHR₂)}]₂2, while metallation of the previously described di-lithium compounds [Li{N(R)C(R^′)CH}₂(C₅H₃-2,6)]Li(tmen)_n (R=SiMe₃, R^′=Bu^t, n=1 or R=SiMe₃, R^′=Ph, n=2) with PdCl₂(PhCN)₂ yielded the novel metallacycles [Pd{{N(H)(R)C(R^′)CH}{N(SiMe₂CH₂)C(R^′)CH}C₅H₃N-2,6}] 3 (R^′=Bu^t) and [Pd{{N(R)C(R^′)CH}{N(R)(H)C(R^′)CH}C₅H₃N-2,6}₂] (R^′=Ph) 4 in moderate to low yield. Compound 3 is unusual in being the first example of a crystallographically characterised PdNSiC heterocycle which is believed to be formed via an intramolecular CH-activation of a trimethylsilyl group by Pd(II). All four compounds were fully characterised by NMR-spectroscopy, microanalysis (not 4) and X-ray diffraction.     

Tin-119 Mössbauer spectral studies in organotin(IV) and tin(II) substituted oxinates

Organotin(IV) compounds of the type, R₂SnL₂ (R = CH₃, C₂H₅, C₄H₉, C₈H₁₇ or C₆H₅ and HL = 2-methyl-8-quinolinol), R₃SnL and R₂SnXL (R = C₆H₅ and X = Cl), SnL′₂ (HL′ = 2- or 5,7-substituted-8-quinolinol) and SnXL (X = Cl) have been synthesized and characterised. The ^119mSn Mössbauer spectra of these along with several other alkyl or aryl tin(IV) substituted oxinates have been recorded at 77°K and from the Mössbauer parameters the probable structures of these compounds are inferred. Bis(5,7-dinitro-8-quinolinolato)dialkyltin(IV) compounds (Q.S. = ∼4.3 mm/sec) are considered to have the two R-groups occupying trans-positions in the octahedral structure. The somewhat large and significantly varying quadrupole splittings observed in the three series of compounds, R₂SnL′₂ studied, may be associated with donor-acceptor interactions.     

Membrane Transport of Inorganic Acids with α- Aminophosphoryl Compounds

Transport of some inorganic acids (HCl, HBr, HClO₄, HNO₃, H₂SO₄, and H₂PO₄) through hydrophobic impregnated membranes with aminophosphoryl compounds of the general formula R ₂ ¹ P(O)CH₂ ⋅ NR²R³ [R¹ = C₄H₉(C₂H₅)CHCH₂O, R² = C₄H₉, R³ = C₈H₁₇; R¹ = R³ = C₈H₁₇, R² = H; R¹ = C₁₀H₂, R² = R³ = C₂H₅; R¹ = C₁₀H₂₁, R² + R³ = (CH₂)₂O(CH₂)₂; R¹ = C₈H₁₇, R² = H, R³ = 2-quinolyl] and dodecylamine as carriers was studied. The membrane phases were solutions of the carriers in phenylcyclohexane and tridecane. General regularities that correlate the structure of an aminophosphoryl compounds to its transport properties toward inorganic acids were established. The largest flows are characteristic of perchloric, nitric, and hydrobromic acids.__________Translated from Zhurnal Obshchei Khimii, Vol. 75, No. 4, 2005, pp. 575–578.Original Russian Text Copyright © 2005 by Garifzyanov, Shirshova, Cherkasov.     

119Sn Mössbauer spectral studies in Sn(IV) and organotin(IV) substituted oxinates

Several Sn(IV) and organotin(IV) compounds of the type SnL₂X₂(X = Cl and HL = 5-acetyl-, benzol-, or phenylazo-, 8-quinolinol), SnX₄ · 2HL′(X = Cl or Br and HL′=8-quinolinol-N-Oxide), R₂SnL₂(R = CH₃, C₂H₅, C₄H₉, C₈H₁₇ or C₆H₅) and R₃SnL(R = C₆H₅) have been synthesized and characterized. The ^119mSn Mössbauer spectra of these compounds have been recorded at 77°K and probable structures from the Mössbauer parameters are inferred. R₂SnL₂ chelates (Q.S = ca. 2.0 mm/sec.) are considered to have the two R-groups occupying cis-positions in the octahedral structure. The Mössbauer spectra of the compounds, SnX₄·2HL′ have been resolved graphically and the quadrupole splitting values (ca. 0.75 mm/sec.) strongly suggest trans-configuration for the Sn(IV) tetrahalide adducts.     

A Series of [Mn6] Complexes with Terminal Functional Groups

A series of [Mn₆O₂(R¹OH)₄(sao)₆(R²COO)₂] complexes with terminal functional groups ( 1 : R¹ = CH₃, R² = HO‐C₆H₄, 2 : R¹ = C₂H₅, R² = H₂N‐C₆H₄, 3 : R¹ = CH₃, R² = Cl‐C₆H₄, 4 : R¹ = CH₃, R² = CH₃S‐C₆H₄, 5 : R¹ = CH₃, R² = I‐C₆H₄, 6 : R¹ = CH₃, R² = pymSCH₂, 7 : R¹ = CH₃, R² = ortho‐pyr‐SCH₃, 8 : R¹ = C₂H₅, R² = (CH₃)₃OOCNHCH₂C₆H₄; sao = doubly deprotonated salicylaldoxime ligand, pym = pyrimidyl, pyr = pyridyl) have been obtained in a reaction of a ligand R²C₆H₄COOH, salicylaldoxime, manganese(II) perchlorate and [NEt₄](OH) in methanol or a 1:1 mixture of ethanol and dichloromethane. In this report, structural aspects as well as preliminary studies of magnetic and thermal properties are presented. Compounds 1 , 3 , 6 , 8 exhibit an antiferromagnetic coupling of the Mn²⁺ ions, whereas 4 and 7 show ferromagnetic interactions. The title compounds may act as starting materials for further derivatization addressing the functional groups.     

O-Halogensilyl-N,N-bis(trimethylsilyl)hydroxylamine – Synthese,Kristallstruktur und Reaktionen

O-Halogenosilyl-N,N-bis(trimethylsilyl)hydroxylamines – Synthesis, Crystal Structure, and Reactions The substitution of halogenosilanes on lithiated N,O-bis(trimethylsilyl)-hydroxylamine in the molar ratio of 1 : 1 occurs on the oxygen atom. The O-halogenosilyl-N,N-bis(trimethylsilyl)hydroxylamines were prepared: RSiF₂ON · (SiMe₃)₂ (R = CMe₃ 1 , CHMe₂ 2 , CH₂C₆H₅ 3 , C₆H₂(CMe₃)₃ 4 ), RR′SiFON(SiMe₃)₂ (R = CMe₃, R′ = C₆H₅ 5 ; R = Me, R′ = C₆H₅ 6 ; R = C₆H₂Me₃, R′ = C₆H₂Me₃ 7 ; R = CH₂C₆H₅, R′ = CH₂C₆H₅ 8 ; R = CHMe₂, R′ = CHMe₂ 9 ; R = CMe₃, R′ = CMe₃ 10 ), RSiCl₂ON(SiMe₃)₂ (R = CMe₃ 11 ; R = Cl 12 ). The reaction of fluorosilanes with lithiated N,O-bis(trimethylsilyl)hydroxylamine in the molar ratio of 1 : 2 leads to the formation of O,O′-fluorosilyl-bis[N,N-bis(trimethylsilyl)hydroxylamines]: RSiF[ON(SiMe₃)₂]₂ (R = CMe₃ 13 ; R = C₆H₅ 14 ). 13 could be prepared in the reaction of 1 with LiON(SiMe₃)₂. Lithiated dimethylketonoxime reacts with 1 to Me₂C=NOSiRF–ON(SiMe₃)₂ [R = CMe₃ ( 15 )]. The first crystal structure of a tris(silyl)hydroxylamine ( 4 ) is shown. The angle at the nitrogen prove a pyramidal geometry.     

Preparation of N,N,N′-tris(trimethylsilyl)amidines; a convenient route to unsubstituted amidines

The tris(trimethylsilyl)amidines RC(NSiMe₃)N(SiMe₃)₂ (R  C₆H₅, p-CH₃C₆-H₄, p-ClC₆H₄, p-MeOC₆H₄, p-Me₂NC₆H₄, p-CF₃C₆H₄, p-C₆H₅C₆H₄ and CF₃) are prepared by the reaction of the respective nitriles with (Me₃Si)₂NLi·OEt₂ in ether to give intermediates RC(NLi)N(SiMe₃)₂. Heating these intermediates with ClSiMe₃ in toluene affords the products, which are isolated by vacuum distillation, in high yield. With 1,4-dicyanobenzene, two equivalents of reagents affords the per(trimethylsilyl)-1,4-diamidine. Hydrolysis of the intermediates with 6N ethanolic HCl affords the unsubstituted amidine hydrochlorides RC(NH)NH₂·HCl (R  C₆-H₅, p-MeOCh₆H₄, p-ClC₆H₄, p-O₂NC₆H₄) in high yield.     

Dialkylamino-bis(trimethylsilyl)amino-chlorborane und ihre Reaktion mit Natrium-bis(trimethylsilyl)amid

Zusammenfassung Verbindungen des Typs R₂NBCIN(Sime ₃)₂ ^* (R=C₂H₅,ⁱC₃H₇, C₆H₁₁, C₆H₅) bleiben bis zu hohen Temperaturen beständig. Sie reagieren jedoch mit NaN(Sime ₃)₂ unter Übertragung einer Methylgruppe von einem Silicium-zu einem Boratom zu N,N-Bis(trimethylsilyl)-tetramethylcyclodisildiazan und R₂NBmeN(Sime ₃) (R=C₂H₅,ⁱC₃H₇).

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Compounds of the type R₂NBClN(Sime ₃)₂ ^* were prepared. (R=C₂H₅,ⁱC₃H₇, C₆H₁₁, C₆H₅. They do not show any tendency to condense thermally under elimination of trimethylchlorosilane. When these silylaminoboranes were allowed to react with NaN(Sime ₃)₂, complicated rearrangements were observed. The compounds in which R=C₂H₅ orⁱC₃H₇ rearranged under formation of N,N-bis(trimethylsilyl)-tetramethylcyclodisildiazane and R₂NBmeN(Sime)₂. In this reaction a migration of a methyl group from silicon to boron occurs.

     

Cationic rhodium tetrafluorobenzobarrelene complexes with diolefin or arene ligands,crystal structures of [Rh(TFB)(arene)] ClO4, (arene = C6Me6, C6H3Me3, C6H4Me2)

The preparation and properties of complexes of the general formulae [Rh(TFB)(diolefin)]ClO₄, [Rh(TFB)(arene)]ClO₄ and [Rh(TFB)L₂]ClO₄, (TFB = tetrafluorobenzobarrelene, L = dimethylsulfoxide and tetrahydrothiophen) are described. The crystal structures of the arene complexes (arene = C₆Me₆, C₆H₃Me₃ and C₆H₄Me₂) have been solved by X-ray methods. The three compounds crystallize in quite similar lattices: R3c, a = b = 27.122, 26.233, 25.731 and c = 17.079, 16.388, 16.256 Å, respectively. δR-plots for about 2000 reflections show the agreement in the refinements carried out up to R-values of 5%, 5% and 4% respectively. The Rh atom is coordinated to the double bonds of the TFB and to the arene ring in all three compounds, but the deviation from planarity of the arene and its relative position with respect to the TFB moiety varies.     

Investigations on organotin,organolead, lead(IV), and lead(II) dithiolates

Bis(triorganometal) 1,2-dithiolates (R₃M)₂S₂R′ [(HS)₂R′ = C₇H₈S₂ for toluene-dithiol-3,4 (H₂TDT); M = Sn, Pb; R = Ph; or (HS)₂R′ = C₁₀H₁₄S₂ for 1,2-dimethyl-4,5-bis(mercaptomethyl)benzene (H₂DBB); M = Sn, R = CH₃, C₆H₅; M = Pb, R = C₆H₅], diorganometal 1,2-dithiolates R₂MS₂R′ [(HS)₂R′ = C₆H₆S₂ for 1,2-dimercaptobenzene (H₂DMB); M = Pb, R = CH₃, C₂H₅, C₆H₅; or (HS)₂R′ = H₂TDT; M = Sn, R = CH₃, C₆H₅; M = Pb, R = C₆H₅; or (HS)₂R′ = H₂DBB; M = Sn, R = CH₃, C₆H₅; M = Pb, R = CH₃, C₂H₂, C₆H₅; or (HS)₂R′ = C₈H₆N₂S₂ for 2,3-dimercaptoquinoxaline (H₂QDT); M = Pb, R = C₆H₅] and some lead(IV) and lead(II) dithiolates Pb(S₂R′)_n [(HS)₂R′ = H₂DMB, n = 2; (HS)₂R′ = H₂TDT, n = 2; (HS)₂R′ = H₂DBB, n = 1 or 2] have been prepared. Vibrational, ¹H NMR, and Mössbauer spectroscopic data are consistent with pentacoordination of tin in R₂SnTDT and with tetracoordination of tin in R₂SnS₂R′ and (R₃Sn)₂S₂R′ in the solid state. The soluble compounds are monomeric in solution. Coupling constants for the methyltin compounds indicate tetracoordination in solution.     

The solid state structure of arene-mercury(II) complexes from magic-angle spinning carbon-13 NMR and the solution carbon-13 NMR of some complexes of mercury(II) with arenes having bulky aliphatic substituents

The cross-polarization magic angle spinning ¹³C NMR spectra of Hg(SbF₆)₂ - 2 Arene (Arene = C₆HMe₅, 1,2,4,5-C₆H₂Me₄, 1,2,3,4-C₆H₂Me₄, or C₆H₆) have been measured. The spectra of the complexes of C₆HMe₅ and 1,2,4,5-C₆H₂Me₄ are consistent with static η¹-bonding of the mercury to the arene at an unsubstituted carbon atom, while the spectra of the 1,2,3,4-C₆H₂Me₄ and C₆H₆ complexes show the arene to have time-averaged C_s or C₂, and C₆ symmetry respectively, at the temperature of measurement (300 K).The reduced temperature ¹³C NMR spectra of Hg(Arene)_n²⁺ (n = 1 or 2; Arene = 1,3,5-C₆H₃R₃ (R = Me, i-Pr, or t-Bu)) in SO₂ solution are also reported and affirm that in these intramolecularly mobile species the mercury bonds in an η¹-manner, with unsubstituted aryl carbon atoms being the strongly preferred point of mercury attachment. This site preference is further demonstrated by the solution ¹³C NMR spectra of Hg(Arene)_n²⁺ (Arene = 1,2,3,4-C₆H₂-Me₄, n = 1 or 2; Arene = 1,4-C₆H₄R₂, R = Me or t-Bu, n = 1). The spectra of the 1,4-C₆H₄R₂ complexes and Hg(p-C₆H₄-t-BuMe)²⁺ provide clear evidence for steric influence of the binding site.Like Hg(C₆Me₆)₂²⁺, but unlike most of the complexes of substituted benzenes which have been studied, Hg(1,3,5-C₆H₃-i-Pr₃)₂²⁺ exchanges only slowly with excess free ligand.     

Crystal structures ofcatena-[diligatocadmium(II) tetra-μ-cyanocadmate(II)] host clathrates: Diamminecadmium(II) tetracyanocadmate(II)-benzene(1/2), diamminecadmium(II) tetracyanocadmate(II)-aniline(1/2), ethylenediaminecadmium(II) tetracyanocadmate(II)-aniline(1/2), and a novel type bis(aniline)cadmium(II) tetracyanocadmate(II)-aniline(2/1)

The crystal structures of the four title clathrate compounds Cd(NH₃)₂Cd(CN)₄ · 2C₆H₆,I, Cd(NH₃)₂Cd(CN)₄ · 2C₆H₅NH₂,II, Cd(NH₂CH₂CH₂NH₂)Cd(CN)₄ · 2 C₆H₅NH₂,III, and Cd(C₆H₅NH₂)₂Cd(CN)₄ · 0.5C₆H₅NH₂,IV, have been analyzed by single crystal X-ray diffraction methods. CompoundI crystallizes in the monoclinic space groupC2/c,a = 12.063(2),b = 12.174(2),c = 14.621(1) Å,β = 90.976(9)°,Z = 4,R = 0.042 for 2388 reflections;II: monoclinic C₂/c,a = 12.1951(9),b = 12.078(1),c = 14.6921(7) Å,β = 93.436(5)°,Z = 4,R = 0.039 for 2374 reflections;III: monoclinicCc,a = 11.027(1),b = 12.0767(9),c = 15.837(1) Å,β = 92.059(9)°,Z = 4,R = 0.041 for 2883 reflections; andIV: monoclinicP2₁/n,a = 15.169(2),b = 16.019(2),c = 8.866(1) Å,β = 95.73(1)°,Z = 4,R = 0.052 for 3612 reflections. The three-dimensionalcatena-[diamminecadmium(II) tetra-μ-cyanocadmate(II)] hosts ofI andII are substantially isostructural to that of the already known Hofmann-Td-type Cd(NH₃)₂Hg(CN)₄ · 2C₆H₆. The three-dimensional en-Td-typecatena-[catena-μ-ethylenediaminecadmium(II) tetra-μ-cyanocadmate(II)] host ofIII, reinforced by the catena-μ-en linking between the octahedral Cd atoms, accommodates the aniline as the guest with a monoclinic distortion from the tetragonal symmetry of the previously reported en-Td-type benzene clathrate. InIV dual behavior of aniline, one as the unidentate ligand in the three-dimensional host and the other as the guest in the cage-like cavity, has been demonstrated.     

Synthesis,X-ray structure and spectroscopy of Cu(II) complexes derived from diacetylazine dioxime

Complexes of Cu(II) with the polydentate diacetylazine dioxime ligand C₈H₁₄N₄O₂ have been synthesized by template and non-template reactions. The crystal structure of [Cu(C₈H₁₃N₄O₂)]₂[ClO₄]₂(C₂H₅OH)₂ has been determined to establish the conformation of the ligand and the coordination of the oxime function. The structural analysis shows that the nearly planar [C₈H₁₃N₄O₂]^? group behaves as a bridging tetradentate ligand. The distorted square-pyramidal coordination about each Cu atom includes three N donors from two oxime and azine and one O donor from the other oxime, the ethanol molecule occupying the apical position. A perchlorate anion is loosely bonded to Cu. The intramolecular Cu…Cu separation is 3.725(2) Å. The compound crystallizes in the centrosymmetric space group P$\text{1}$ triclinic lattice with refined lattice parameters of a = 11.963(8) Å, b = 9.784(7) Å, c = 7.501(6) Å, α = 90.69(4)°, β = 104.53(4)°, γ = 90.83(4)°, V = 849.7 ų and Z = 2. Full-matrix least-squares refinement of 1490 independent reflexions led to final discrepancy indices, R = 0.059, and R_w = 0.065. The Cu centres are highly coupled as indicated by the ESR spectrum. There is no evidence that the C₈H₁₄N₄O₂ ligand stabilizes unusual oxidation states of Cu.     

Cu(I) hexafluorosilicate π-complex with N,N′-diallylpiperazinium, [Cu(H2O)2.5{μ-C4H8N2H2(C3H5)2}0.5]SiF6·H2O: Synthesis and crystal structure

This paper reports the ac electrochemical synthesis of the crystals of Cu(I) hexafluorosilicate π-complex with N,N′-diallylpiperazinium of the composition [Cu(H₂O)_2.5{μ-C₄H₈N₂H₂(C₃H₅)₂}_0.5]SiF₆·H₂O, i.e., the π-complex of Cu(I) synthesized for the first time, where the Cu(I) atom simultaneously coordinates three H₂O molecules. The crystals are monoclinic: space group P2₁/a, a = 13.470(6) Å, b = 10.025(6) Å, c = 9.864(5) Å, γ = 112.19(4)°, V = 1233(2) ų, Z = 4, R = 0.0555 for 1252 independent reflections, R _w = 0.0634 for 1145 reflections with F ≥ 4σ(F). The structure consists of the {(H₂O)_2.5Cu(C₄H₈N₂H₂(C₃H₅)₂)Cu(H₂O)_2.5} dimers and the Sif ₆ ^2? anions bonded through hydrogen contacts O-H…F and C-H…F.     

Zur Reaktion des 1-Lithio-3-(trimethylsilyl)-2,2,4,4,6,6-hexamethylcyclotrisilazans mit Silicium-Fluor-Verbindungen

The Reaction of 1-Lithio-3-(trimethylsilyl)-2,2,4,4,6,6-hexamethylcyclotrisilazane with Silicon-Fluoro Compounds 1-lithio-3-(trimethylsilyl)-2,2,4,4,6,6-hexamethylcyclotrisilazane reacts with fluoroorganylsilanes RR′SiF₂ (R = F, CH₃, sec-C₄H₉; R′ = CH₃, sec-C₄H₉, C₆H₅) to give mono- and disubstituted trimethylsilylhexamethylcyclotrisilazanes and LiF. The mass-, ¹H- and ¹⁹F-n.m.r. spectra are reported.     

Preparation,structures and reactivity of two new addition compounds of carbodiimides with ditungsten hexa-t-butoxide

The reactions of ditungsten hexa-t-butoxide, W₂(OCMe₃)₆, with dicyclohexylcarbodiimide, C₆H₁₁NCNC₆H₁₁, and diisopropylcarbodiimide, Me₂CHNCNCHMe₂, afford the 1:1 adducts, [W(OCMe₃)₃]₂(μ-C₆H₁₁NCNC₆H₁₁), 1, and [W(OCMe₃)₃]₂(μ-C₃H₇NCNC₃H₇), 2, respectively. These products were each shown by X-ray crystallography to be structurally homologous to the previously reported [W(OCMe₃)₃]₂(μ-CH₃C₆H₄NCNC₆H₄CH₃) and similar to [W(OCMe₃)₃(μ-C₆H₅NCO). It has been shown that the [W(OCMe₃)₃]₂(μ-RNCNR) compounds fail to react with further RNCNR, with PhNCO, PMe₃, LiOCMe₃ or LiOCHMe₂, CO or CO₂, and also that [W(OCMe₃)₃]₂(μ-PhNCO) does not afford any defined product when treated with C₆H₁₁NCNC₆H₁₁. Compounds 1 and 2 were fully characterized by IR and NMR spectroscopy and by X-ray crystallography. Compound 1 crystallizes in space group C2/c with unit cell dimensions a = 13.481(3) Å, b = 18.129(4) Å, c = 18.244(2) Å, β = 97.54(1)°, V = 4420(2) ų, Z = 4. It was refined to R = 0.0375, R_w = 0.0475. Compound 2 crystallizes in space group P2₁/c with unit cell dimensions a = 14.752(2) Å, b = 12.157(3) Å, c = 22.189(3) Å, β = 97.03(2)°, V = 3949(2) ų, Z = 4. The structure was refined to R = 0.053, R_w = 0.059. Each molecule has C₂-symmetry, with two W(OCMe₃) units united by RNCNR bridges across WW distances of 2.490(1) and 2.485(1) Å for 1 and 2, respectively.     

Alkoxylierung von bis(trimethylsilyl)-aminofluorsilanen,sowie siloxanbildung unter äthereliminierung

The reaction of bis(trimethylsilyl)aminofluorsilanes, (Me₃Si)₂NSiF₂R (R = CH₃ or F), with sodium alcoholates or sodium phenylate yields under elimination of NaF alkoxy- and aryloxy-aminofluorosilanes of the composition (Me₃Si)₂NSiF(R)OR′(R′ = CH₃, C₂H₅, C₃H₇, C₆H₅). A disiloxane is formed by thermal elimination of diethyl ether from bis(trimethylsilyl)aminomethylfluoroethoxysilane. The IR, mass, ¹H and ¹⁹F NMR spectra of the above-mentioned compounds are reported. ab]Die Reaktion von Bis(trimethylsilyl)-aminofluorsilanen des Typs (Me₃Si)₂NSiF₂R (R = F, CH₃) mit Natriumalkoholaten und Natriumphenolat führt unter NaF-Abspaltung zu Alkyl- und Aryloxyaminofluorsilanen der Zusammensetzung: (Me₃Si)₂NSiF(R)OR′ (R′ = CH₃, C₂H₇, C₆H₅, C₆H₅). Ein Disiloxan könnte durch die thermische Eliminierung von Diäthyläther aus Bis(trimethylsilyl)aminomethyl-fluor-äthoxy-silylarnin erhalten werden.Die IR-, Massen-, ¹H- und ¹⁹F-NMR-Spektren der dargestellten Verbindungen werden mitgeteilt.