Silicium-stickstoff-fluorverbidungen: V. Darstellung neuer silylaminofluorsilane

Compounds of the composition RR′SiFNR″Si(CH₃)₃ (R = H, F, CH₃, C₂H₅, C₃H₇, C₂H₃, C₆H₅, C(CH₃)₃; R = F, CH₃, C₆H₅; R″ = CH₃, C(CH₃)₃, Si(CH₃)₃) are obtained by the reaction of silicontetrafluoride or organo-substituted silicon-fluorides with the lithium salts of alkylsilylamines in a molar ratio of $\text{1}\text{1}$. The disubstituted compounds RSiF(NR′Si(CH₃)₃)₂ (R = H, F, CH₃, C₂H₃, C₆H₅; R′ = CH₃, C(CH₃)₃) result when the reactants are in a $\text{1}\text{2}$ molar-ratio. Likewise the unsymmetrical siliconfluorsilylamines of the formulae F₂Si(NRSi(CH₃)₃) (NR′Si(CH₃)₃) (R = CH₃, R′ = C(CH₃)₃), as well as the trisubstituted compounds FSi(NCH₃Si(CH₃)₃)₃ and FSi(NCH₃Si(CH₃)₃)₂(N(Si(CH₃)₃)₂) were made. By reacting phenyltrifluorsilane with dialkylamines ($\text{1}\text{2}$) C₆H₅SiF₂NR₂(R = CH₃, C₂H₅) was obtained. The IR-, mass-, ¹H and ¹⁹F NMR spectra of the above-mentioned compounds are reported.     

Unterschiedliche Cyclisierungsmechanismen von Aminofluorsilanen

Different Mechanisms of the Cyclisation of Aminofluorosilanes The reaction of aminofluorosilanes of the type RR′SiFNHR″ (R = H, F, CH₃, C₂H₃, C₆H₅, C(CH₃)₃; R′ = C(CH₃)₃, NiC₃H₇Si(CH₃)₃, NC(CH₃)₃Si(CH₃)₃, N[Si(CH₃)₃]₂; R″ = iC₃H₇, C(CH₃)₃, C₆H₅) with butyllithium depends on the steric influence of the ligands. With increasing size of the ligands the reaction takes its pathway from the substitution under LiF elimination via dimerisation with additional elimination of butan to the C? H cleavage and cyclisation via a methylen group. A further increase of the size of the substituted groups leads through the intermediate formation of a silicenium-ylid to ring closure reactions. These occure by migration of a methanid ion leading to intermolecular nucleophilic substitution. The isolated acyclic and heterocyclic compounds are described and the mass and ¹H-n.m.r. spectra are reported.     

Darstellung neuer Alkylaminofluorsilane

Preparation of New Alkylaminofluorosilanes Aminofluorosilanes of the composition RSiF₂NR′R″ (R = H, CH₃, C₂H₃, C₆H₅; R′ = Si(CH₃)₃; R″ = C(CH₃)₃; R′ = R″ = i-C₃H₇), as well as C₆H₅SiF₂N[C(CH₃)₂CH₂]₂CH₂ are obtained by the reaction of fluorosilanes with the lithium salts of the corresponding amines in a molar ratio 1:1. The further reaction of these compounds with the lithium salts of alkylamines and anilin leads to the formation of the diaminofluorosilanes RSiFNR′R″NHR? (R? = C(CH₃)₃, i-C₃H₇, C₆H₅). The ¹H, ¹⁹F, ²⁹Si n.m.r. and mass spectra of the above mentioned compounds are reported.     

Spektroskopische Untersuchungen an Siliciumverbindungen. XXXI. Schwingungsverhalten von p-substituierten N,N-Bistrimethylsilylanilinen

The following p-substituted N,N-bis-trimethlsilyl anilines p-X? C₆H₄? N[Si(CH₃)₃]₂ are prepared by silylation of free amines: X = H, CH₃, C₂H₅, CH₃O, CH₃CO, F, Cl, Br, J, CN, C₆H_S, (CH₃)₃SiO, and [(CH₃)₃Si]₂N, and the isotopic derivatives C₆H₅? ¹⁵N[Si(CH₃)₃]₂ and C₆D₅N[Si(CH₃)₃]₂. The vibrational spectra are reported and assigned. The molecular symmetry of p-[(CH₃)₃Si]₂N? C₆H₄? N[Si(CH₃)₃]₂ is determined. The influence of the mass of the substituents X on the positions of the ν_sSiNSi vibrational frequencies is discussed.     

Group 12 metal complexes of tetradentate N2O2–Schiff-base ligands incorporating pyrazole: Synthesis,characterisation and reactivity toward S-donors,N-donors,copper and tin acceptors

New [M(Q)₂(X)] derivatives (where M=Zn, Cd or Hg; Q=1-phenyl-3-methyl-4-R(C=O)-pyrazolon-5-ato; in detail: Q_L, R=C₆H₅; Q_B, R=CH₂C(CH₃)₃; Q_S, R=CH(C₆H₅)₂; X=EtOH or H₂O) have been synthesised and characterised. These compounds undergo a condensation reaction with the appropriate diamine in ethanol, affording novel Schiff-base metal derivatives [M(diaquo)bis(1-phenyl-3methyl-4-R(C=N)-pyrazolone)(CH₂)_ndiimmine] (LⁿH₂, R=C₆H₅, n=2, 3 or 4; BⁿH₂, R=CH₂C(CH₃)₃, n=2, 3 or 4; SⁿH₂, R=CH(C₆H₅)₂, n=2 or 3; M=Zn, Cd or Hg). These compounds possess a six-coordinate metal environment. A ¹¹³Cd NMR study has been carried out on cadmium derivatives. The derivative [Zn(L²)(H₂O)₂] reacted with CuCl₂ and with Cu(ClO₄)₂ affording [Cu(Q_L)₂] and [Cu(en)₂](ClO₄)₂ (en=ethylendiamine), respectively, upon breaking of the C=N bond in the Schiff-base donor. In addition [Zn(L²)(H₂O)₂] reacted with 1,10-phenanthroline (phen), yielding the derivative [Zn(Q_L)₂(phen)]. Whereas when [Zn(L²)(H₂O)₂] reacted with CdCl₂, formation of [Cd(L²)(H₂O)₂] due to exchange of the metal centre was observed. Finally the derivative [Zn(L²)(Hmimt)], likely containing a five-coordinate ZnN₂O₂S central core, has been obtained from the exchange reaction between [Zn(L²)(H₂O)₂] and 1-methylimidazolin-2-thione (Hmimt).     

Bildung siliciumorganischer Verbindungen. 66. (H2Si?CH2)2 und Si-substituierte Derivate

Formation of Organosilicon Compounds. 66. (H₂Si? CH₂)₂ and Si-substituted Derivatives (H₂Si? CH₂)₂ 1 is formed in the reaction of (Cl₂Si? CH₂)₂ with LiAlH₄. In 1 , the halogenation of the SiH bond is so much preferred compared to the ring cleavage reaction, that 1 reacts with Cl₂ or Br₂ to form successively all compounds form 1-monochlor-1,3-disilacyclobutane to (X₂Si? CH₂)₂ (X = Cl, Br). The stability of the 1,3-disilacyclobutane skeleton towards HBr or Br₂ increases as the electronegativity of the Si-substituents increases. Thus, (Cl₂Si? CH₂)₂ is cleaved neither by HBr nor by Br₂, whereas e. g. [H(C₆H₅)Si? CH₂]₂ reacts to [Br(C₆H₅)Si? CH₂]₂ with Br₂, but yields meH(C₆H₅)Si? CH₂? SiBr(C₆H₅)H (me = CH₃) with HBr. In [me(C₆H₅)Si? CH₂]₂, the four-membered ring is cleaved by Br₂ as well as by HBr. The ¹H-, ²⁹Si- and ¹³C-n.m.r. data are reported.     

Perhalophenyl complexes of palladium(II) containing keto-stabilized phosphorus ylides of the type Ph2P(CH2)nPPh2CHC(O)R

From suitable perhalophenyl derivatives of palladium(II), viz.: Pd(C₆F₅)₂-(SC₄H₈)₂, [Pd(μ-X′) (C₆X₅)₂]₂(NBu₄)₂, [Pd(μ-Cl)(C₆X₅)(SC₄H₈)]₂ (X = F, Cl, X′ = Cl, Br), new complexes of various types have been prepared, viz.: trans-Pd(C₆F₅)₂(Y)₂, Pd(C₆X₅)₂(Y), PdCl(C₆X₅)(Y) (X = F, Cl). The neutral ligand Y is a keto-stabilized phosphorus ylide of the type Ph₂P(CH₂)_nPPh₂CHC(O)R (n = 1, R = CH₃, C₆H₅; n = 2, R = C₆H₅) acting in a terminal monodentate P-donor or a bidentate chelate P,C-donor mode. The reaction of PdCl(C₆F₅)(Y) complexes with HCl leads to the corresponding PdCl₂(C₆F₅)(YH) complexes in which the phosphonium cation [YH]⁺ behaves as monodentate P-donor at its phosphinic end.IR and ³¹P NMR spectroscopy were used to decide the coordination mode of the ligands and, in some cases, to reveal the presence of two isomers.     

Reaktion von Alkyl- und Arylchlorsilanen mit Phosph(III) en-imidamiden

The reaction of RSiCl₃ (R=CH₃, C₂H₅, C₆H₅) and R₂SiCl₂ (R=CH₃) with one mole of the phosphenimidous amides R₂N–P=NR [R=R=Si(CH₃)₃; R=Si(CH₃)₃, R=C(CH₃)₃] yieds a four membered PN₂Si-ring system under elimination of (CH₃)₃SiCl.     

Reaction of [Fe4(μ3-CCH3)(CO)12]− with alkynes: Ethylidyne-alkyne coupling on a tetranuclear iron cluster anion

The [Fe₄(μ₄-η³-C(CH₃)C(R)C(R′)(μ-CO)₂(CO)₉]⁻ cluster anions have been obtained by the reaction of the Fe₄(μ₃-CCH₃)(CO)₁₂⁻ anion with RCCR alkynes in boiling 3-pentanone. In the cases in which R = R′ = C₆H₅ or CH₃, and R = H, R′ = C₆H₅ or t-Bu, only one isomer has been detected. In the case in which R = CH₃, and R′ = C₆H₅, two isomers with the C(CH₃)C(C₆H₅)C(CH₃) and C(CH₃)C(CH₃)C(C₆H₅) fragments have been identified.     

Cationic Allyl Complexes of the Rare‐Earth Metals: Synthesis,Structural Characterization,and 1,3‐Butadiene Polymerization Catalysis

Monocationic bis‐allyl complexes [Ln(η³‐C₃H₅)₂(thf)₃]⁺[B(C₆X₅)₄]^? (Ln=Y, La, Nd; X=H, F) and dicationic mono‐allyl complexes of yttrium and the early lanthanides [Ln(η³‐C₃H₅)(thf)₆]²⁺[BPh₄]₂^? (Ln=La, Nd) were prepared by protonolysis of the tris‐allyl complexes [Ln(η³‐C₃H₅)₃(diox)] (Ln=Y, La, Ce, Pr, Nd, Sm; diox=1,4‐dioxane) isolated as a 1,4‐dioxane‐bridged dimer (Ln=Ce) or THF adducts [Ln(η³‐C₃H₅)₃(thf)₂] (Ln=Ce, Pr). Allyl abstraction from the neutral tris‐allyl complex by a Lewis acid, ER₃ (Al(CH₂SiMe₃)₃, BPh₃) gave the ion pair [Ln(η³‐C₃H₅)₂(thf)₃]⁺[ER₃(η¹‐CH₂CH?CH₂)]^? (Ln=Y, La; ER₃=Al(CH₂SiMe₃)₃, BPh₃). Benzophenone inserts into the La? C_allyl bond of [La(η³‐C₃H₅)₂(thf)₃]⁺[BPh₄]^? to form the alkoxy complex [La{OCPh₂(CH₂CH?CH₂)}₂(thf)₃]⁺[BPh₄]^?. The monocationic half‐sandwich complexes [Ln(η⁵‐C₅Me₄SiMe₃)(η³‐C₃H₅)(thf)₂]⁺[B(C₆X₅)₄]^? (Ln=Y, La; X=H, F) were synthesized from the neutral precursors [Ln(η⁵‐C₅Me₄SiMe₃)(η³‐C₃H₅)₂(thf)] by protonolysis. For 1,3‐butadiene polymerization catalysis, the yttrium‐based systems were more active than the corresponding lanthanum or neodymium homologues, giving polybutadiene with approximately 90 % 1,4‐cis stereoselectivity.     

Synthesis and structural characterisation of the mixed-metal cluster cation [Nb(η5-C5H4R)2{AuP(C6H5)3}2]+ with R = H or Si(CH3)3

Triangular “NbAu₂” cluster compounds have been prepared by the reaction of [Nb(η⁵-C₅H₄R)₂H₃] (R = H, Si(CH₃)₃) with gold(I) salts and the structure of [Nb{η⁵-C₅H₄Si(CH₃)₃}₂{AuP(C₆H₅)₃}₂] PF₆ has been determined by X-ray diffraction.     

Umsetzung von N-Trimethylmetall(IVb)-trialkylphosphiniminen mit Halogenwasserstoffen

Reaction of N-Trimethylmetal(IVb) Trialkylphosphine Imines with Hydrogen Halides Investigations of the reaction of N-trimethylmetal(IVb)-substituted phosphine imines with hydrogen have been carried out. With one mole of HX phosphonium halides of the general formula [R₃P? NH? MMe₃]^⊕X^? (R = CH₃, C₂H₅; M = Si, Ge, Sn; X = Cl, Br, J) are obtained. A second mole of HX causes M? N bond cleavage, yielding aminophosphonium halides, [R₃P? NH₂]^⊕X^?.     

Sulfenamides as ligands in transition metal chemistry Pentacarbonyl(Sulfenamide)Chromium(0) Complexes

The complexes Cr(CO)₅(R′SNR₂) [R′ = CH₃; NR₂ = N(CH₃)₂, N(C₄H₈)O. R′ = C₆H₅; NR₂ = N(CH₃)₂, N(C₄H₄)O, N(CH₂? C₆H₅)₂, N(C₆H₁₁)₂] have been prepared by reaction of the sulfenamides with Cr(CO)₅ · THF and characterized by analytical and spectroscopic methods. The IR, ¹H-NMR, UV-VIS, and mass spectra of the complexes support the coordination of the sulfenamide via the sulfur atom. π-acceptor abilities of sulfenamides in the prepared coordination compounds, determined from IR and UV-VIS data, were compared with those of other divalent sulfur conpounds.     

Novel D- and T-functionalized Polysiloxane Matrices for Reactions in Interphases

New hydrocarbon bridged co-condensation agents of the type RSi(OMe)₂(CH₂)_zC₆H₄(CH₂)_z(OMe)₂SiR { 3[Ph(1,4-C₃D⁰)₂] , z = 3, R = Me; 3[Ph(1,4-C₃T⁰)₂] , z = 3, R = OMe; 4[Ph(1,4-C₃D⁰)₂] , z = 4, R = Me} were synthesized by hydrosilylation of the corresponding α,ω-dienes CH₂=CH–(CH₂)_z–2–C₆H₄–(CH₂)_z–2–CH=CH₂ [z = 3 ( 1 ), 4 ( 2 )] with HSiR(OMe)₂ (R = Me, OMe). These silane monomers were sol-gel processed, partially with MeSi(OMe)₃ ( T ⁰) to give the polysiloxanes 3 a , 3 b , 4 c , 3 d , 3 e , 4 f , and 3 ab (Table 1, Schemes 2 and 3); D = D type silicon atom (two oxygen neighbors), T = T type of silicon atom (three oxygen neighbors). The relative amounts of T and D silyl species and the degrees of condensation were determined by ²⁹Si and ¹³C CP/MAS NMR spectroscopic investigations. ²⁹Si and ¹³C CP/MAS NMR relaxation time studies (T_SiH, T_CH, T_1ρH), and 2 D WISE NMR experiments were applied to get knowledge about the polymer dynamics. For the first time protons of such polysiloxane systems were detected by ¹H SPE/MAS NMR measurements in suspension. Mobility studies were carried out in different solvents. Furthermore the swelling capacities of the polymers 3 a , 3 b , and 4 c in different solvents and the BET surface areas of all materials were investigated. SEM micrographs show the morphology of 3 a and 3 b .     

Synthese und reaktivität von dienylmetall-verbindungen XXVIII. Über kationen des typs [C5H5Fe(CO)L(EME2)]+ (E = S,Se, Te)

The chiral cations, [CpFe(CO)(EMe₂)L]⁺, are obtained both by reaction of [CpFe(CO)(EMe₂)₂]⁺ with the ligands (L) by heating, and by irradiation of the cations [C₅H₅Fe(CO)₂EMe₂]⁺ in the presence of L (E = S, Se, Te; L = PR₃, AsR₃, SbR₃). The inversion about the chalcogen atom is investigated by DNMR spectrocopy. Compounds of the type [C₅H₅Fe(TeMe₂)L₂]⁺] are formed by irradiation of [C₅H₅Fe(CO)₂(TeMe₂)]⁺ and the ligands (L₂ = 2 PR₃, R = CH₃, OCH₃, OC₆H₅; L₂ = R₂P(CH₂)_nPR₂, R = C₆H₅, n = 1,2,3). ⁷⁷Se and ¹²⁵Te NMR data vary according to the donor properties of the ligand L in the complexes.     

U¨bergangsmetall—Carbin—Komplexe: LXIV. Von equatorialen,zweikernigen silylcarben-komplexen des rheniumsU¨ber einen neuartigen kationischen silylcarbin-komplex zu axialen carben-komplexen

Decacarbonyldirhenium reacts with LiSi(C₆H₅)₃ to yield, on subsequent alkylation with FCH₃SO₃ or (C₂H₅)₃OBF₄, the equatorial nonacarbonyl[triphenylsily(alkoxy)carbene] dirhenium complexeseq-(CO)₉Re₂C(OR)Si(C₆H₅)₃(Ia, R - CH₃; Ib, R - C₄H₈OCH₃; Ic. R - C₂H₅). Reactions of these compounds with Al₂Cl₆ or Al₂Br₆ produce novel binuclear, cationic silycarbyne complexes, ax-[(CO)₉Re₂CSi(C₆H₅)₃]⁺ AlX₄^- (IIa, X - Cl; IIb, X - Br). Treatment of these complexes with alcohols results in formation of the axial nonacarbonyl(carbene)dirhenium complexesax-(CO)₉Re₂C(OR)Si(C₆H₅)₃ (IIIa, R - CH₃; IIIb, R - C₂H₅). The isomeric carbene complexes Ia and IIIa react with dialkylamine affording the isomeric aminocarbene complexeseq-(CO)₉Re₂C(CH₃)₂]-Si(C₆H₅)₃ (V) andax-(CO)₉Re₂Cl(NR₂)Si(C₆H₅)₃ (IVa, R - CH₃; IVb, R - C₂H₅). Reaction conditions, properties and spectroscopic data of the new compounds are reported.     

Reaktion von Alkyl- und Arylchlorsilanen mit Phosph(III) en-imidamiden

The reaction of RSiCl₃ (R=CH₃, C₂H₅, C₆H₅) and R₂SiCl₂ (R=CH₃) with one mole of the phosphenimidous amides R₂N–P=NR [R=R=Si(CH₃)₃; R=Si(CH₃)₃, R=C(CH₃)₃] yieds a four membered PN₂Si-ring system under elimination of (CH₃)₃SiCl.     

Derivate des borabenzols: XVI. (Borinato)(cyclobutadien)cobalt-komplexe mit tetramethyl- und tetraphenylcyclobutadien-liganden. Synthese,elektrophile aromatische substitution und ringgliedsubstitution am borinato-liganden

The preparation of (borinato)(cyclobutadiene)cobalt complexes from the reactions of Co(C₅H₅BR)(1,5-C₈H₁₂) with acetylenes C₂R′₂ and of [C₄(CH₃)₄]Co(CO)₂I with Tl(C₅H₅BR) (R,R′ = CH₃, C₆H₅) is described.In electrophilic substitution reactions Co(C₅H₅BCH₃)[C₄(CH₃)₄] (IVa) is more reactive than ferrocene. CF₃CO₂D effects H/D-exchange in the α-position of the borabenzene ring within a few minutes at ambient temperature and in the γ-position within less than four hours Friedel-Crafts acetylation with CH₃COCl/AsCl₃ in CH₂Cl₂ affords the 2-acetyl and the 2,6-diacetyl derivative of IVa. With the more active catalyst AlCl₃, ring-member substitution is effected to give cations [Co(arene)C₄(CH₃)₄]⁺ (arene = C₆H₅CH₃, 2-CH₃C₆H₄COCH₃). Vilsmeier formylation gives the 2-formyl derivative of IVa. The acyl derivatives Co(2-R¹CO-6-R²C₅H₃BCH₃)[C₄(CH₃)₄] (R¹ = CH₃, R² = H, CH₃CO and R¹ = R² = H) transform to the corresponding cations [Co(ortho-R¹R²C₆H₄)C₄(CH₃)₄]⁺ in superacidic media. The mechanistic relationship between acylation and ring-member substitution is discussed in detail.     

Metallkomplexe mit biologisch wichtigen Liganden. CLVII [1] Halbsandwich‐Komplexe mit Isocyanoacetylaminosäureestern und Isocyanoacetyldi‐ und tripeptidestern („Isocyano‐Peptide”︁)

Metal Complexes of Biologically Important Ligands, CLVII [1] Halfsandwich Complexes of Isocyanoacetylamino acid esters and of Isocyanoacetyldi‐ and tripeptide esters (?Isocyanopeptides”?) N‐Isocyanoacetyl‐amino acid esters CNCH₂C(O) NHCH(R)CO₂CH₃ (R = CH₃, CH(CH₃)₂, CH₂CH(CH₃)₂, CH₂C₆H₅) and N‐isocyanoacetyl‐di‐ and tripeptide esters CNCH₂C(O)NHCH(R¹)C(O)NHCH(R²)CO₂C₂H₅ and CNCH₂C(O)NHCH(R¹)C(O)NHCH (R²)C(O)NHCH(R³)CO₂CH₃ (R¹ = R² = R³ = CH₂C₆H₅, R² = H, CH₂C₆H₅) are available by condensation of potassium isocyanoacetate with amino acid esters or peptide esters. These isocyanides form with chloro‐bridged complexes [(arene)M(Cl)(μ‐Cl)]₂ (arene = Cp*, p‐cymene, M = Ir, Rh, Ru) in the presence of Ag[BF₄] or Ag[CF₃SO₃] the cationic halfsandwich complexes [(arene)M(isocyanide)₃]⁺X^? (X = BF₄, CF₃SO₃).     

Cyclopentadienyleisen-komplexe mit P(OR)3-liganden; Synthese und spektroskopische charakterisierung

Reactions of reactive cyclopentadienyliron complexes C₅H₅Fe(CO)₂I, [C₅H₅Fe(CO)₂THF]BF₄, [C₅H₅Fe(CO)((CH₃)₂S)₂]BF₄ and [C₅H₅Fe(p-(CH₃)₂C₆H₄)]PF₆ with P(OR)₃ as ligands (R = CH₃, C₂H₅, i-C₃H₇ and C₆H₅) lead to the formation of the complex compounds C₅H₅Fe(CO)_2?n(P(OR)₃)_nI and [C₅H₅Fe(CO)_3?n(P(OR)₃)_n]X (n = 1, 2 and n = 1–3, X = BF₄, PF₆). Spectroscopic investigations (IR, ¹H, ¹³C and ³¹P NMR) indicate an increase of electron density on the central metal with increasing substitution of CO groups by P(OR)₃ ligands. The stability of the compounds increase in the same way.