Neuartige basische Liganden für die homogenkatalytische Methanolcarbonylierung, XXXI Kationische Bis(Ether-Phosphan)metall-Komplexe der Nickeltriade mit fluktuierendem Verhalten / Novel Basic Ligands for the Homogeneous Catalytic Methanol Carbonylation, XXXI Cationic Bis(Ether-Phosphine)Metal Complexes of the Nickel Triad with Fluxional Behavior

1991 ◽  
Vol 46 (4) ◽  
pp. 432-439 ◽  
Author(s):  
Ekkehard Lindner ◽  
Johannes Dettinger
Keyword(s):  
Metal Complexes ◽  
Nmr Spectra ◽  
Palladium Complexes ◽  
Phosphine Ligands ◽  
Temperature Dependent ◽  
H Nmr ◽  
Phosphine Complexes ◽  
Metal Phosphides ◽  
Ether Oxygen ◽  
Insight Into

The (ether-phosphine) ligands R2PCH2C5H9O (1a-c) [R = Ph (a), Cy (= cyclo-C6H11) (b), n-C3H7 (c); C5H9O = tetrahydropyranyl] are obtained from the corresponding alkali metal phosphides MPR2 (M = Li, Na) and 2-chloromethyltetrahydropyran in ether. Reaction of 1 a-c with either Cl2M(COD) (COD = 1,5-cyclooctadiene) or [Ni(OH2)6]Cl2 in a2:1 ratio leads to the bis(ether-phosphine)metal complexes Cl2M(R2P∾O)2 trans-2b,c, trans-3b, cis-2a,b, cis-3a, and 4a [M = Pd (2), Pt (3), Ni (4)], in which the ligands 1a-c are η1-P-coordinated. In 2—4 Cl- is abstracted by AgClO4 to give the cationic trans-bis(ether-phosphine) complexes [ClM(R2P ∾ O)(R2P~O)][ClO4] (5a, 6a-c, 7a) [M = Ni (5), Pd (6), Pt (7); P∾O = η1-P-coordinated; P~O = η2-O,P-coordinated]. In contrast to 7a, the nickel and palladium complexes 5a and 6a-c show fluxional behavior as demonstrated by temperature dependent 31P{1H} NMR spectra. The coalescence temperatures and estimated free energie enthalpies ΔG≉ of 5a and 6a-c are compared with the corresponding data of the complexes [ClPd(Ph2P ∾ O)(Ph2~O)][ClO4] (8a-10a) [O,P ligand = Ph2PCH2C4H7O (8a), Ph2PCH2C4H7O2 (9a), Ph2PCH2CH2OCH3 (10a)] and give an insight into the relative basicity of the ether oxygen atoms.

UbergangsmetalIkomplexe mit Schwefelliganden, CXV+. Protonierung und Alkylierung der Thiolatdonoren von Ru(II)-Komplexen mit [Ru(′buS5′)]-Fragmenten (′buS5–H2 = 2,2′-Bis(2-mercapto-3,5-di-t-butylphenylthio)diethylsu!fid)/Transition Metal Complexes with Sulfur Ligands, CXV+. Protonation and Alkylation of Thiolate Donors in Ru(II) Complexes with [Ru(′buS5′)] Fragments (′buS5′–H2 = 2,2′-Bis(2-mercapto-3,5-di-t-butylphenylthio)diethylsulfide)

1995 ◽  
Vol 50 (11) ◽  
pp. 1729-1738 ◽  
Author(s):  
Dieter Sellmann ◽  
Christine Rohm ◽  
Matthias Moll
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Binuclear Complex ◽  
Nmr Spectra ◽  
Temperature Dependent ◽  
Electron Densities ◽  
H Nmr ◽  
Oxonium Salts

Reaction of meso-[Ru(L)(′buS5′)] complexes (L = CO (1), PPh3, PCy3) with one equivalent of oxonium salts R3OBF4 (R = CH3, C2H5) yields the C1 symmetrical monoalkyl derivatives [Ru(L)(′buS5′-R)]BF4 (L = CO, R = CH3 (2), C2H5 (3); L = PPh3, R = CH3 (5); L = PCy3, R = CH3 (6)), in which one of the thiolate donors of the starting complexes is alkylated diastereospecifically. Monoalkylation of the binuclear complex [Ru(′buS5′)]2 leads to C1 symmetrical [Ru(′buS5′-CH3)]2(BF4)2 (7) which gives the hydrazine complex [μ-N2H4{Ru(′buS5′-CH3)}2](BF4)2·N2H4 (9) upon reaction with N2H4.Reaction of 1 with 1.5 equivalents of CF3SO3H yields the isolable thiol complex [Ru(CO)(′buS5′-H)]CF3SO3·0.5 CF3SO3H (4). The 1H-NMR spectra are temperature-dependent and indicate exchange of the thiol proton between the thiolate donors of the ′buS5′2- ligand. Twofold protonation of 1 could only be proved IR-spectroscopically, dialkylation of 1, however, yields isolable [Ru(CO)(′buS5′-(CH3)2)](BF4)2 (8) as a mixture of diastereomers.The IR stretching frequencies ν(CO) of the CO complexes indicate that the electron densities at the ruthenium centers are decreased and the Ru-L bonds are weakened. However, the ligands L in the [Ru(L)(′buS5′-R)]BF4 complexes do not exchange more readily than in the parent complexes.

Preparation, properties and structure of some intermediate nido- and arachno-monocarbaboranes

1981 ◽  
Vol 46 (10) ◽  
pp. 2345-2353 ◽  
Author(s):  
Karel Baše ◽  
Bohumil Štíbr ◽  
Jiří Dolanský ◽  
Josef Duben
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Nmr Spectra ◽  
Liquid Ammonia ◽  
X Ray Diffraction ◽  
X Ray ◽  
H Nmr ◽  
Starting Compound

The 6-N(CH3)3-6-CB9H11 carbaborane reacts with sodium in liquid ammonia with the formation of 6-CB9H12- which was used as a starting compound for preparing the 4-CB8H14, 9-L-6-CB9H13 (L = (CH3)2S, CH3CN and P(C6H5)3), 1-(η5-C5H5)-1,2-FeCB9H10-, and 2,3-(η5-C5H5)2-2,31-Co2CB9H10- carboranes. The 4-CB8H14 compound was dehydrogenated at 623 K to give 4-(7)-CB8H12 carborane. Base degradation of 6-N(CH3)3-6-CB9H11 in methanol resulted in the formation of 3,4-μ-N(CH3)3CH-B5H10. The structure of all compounds was proposed on the basis of their 11B and 1H NMR spectra and X-ray diffraction was used in the case of the transition metal complexes.

Rotationsbarriere der Endgruppen bei Poly- methinoxonolen verschiedener Kettenlänge / Rotation Barrier of the End Groups of Polymethine Oxonols with Different Chain Lengths

1976 ◽  
Vol 31 (8) ◽  
pp. 1017-1018 ◽  
Author(s):  
H. Oehling ◽  
F. Baer
Keyword(s):  
Nmr Spectra ◽  
Rotation Barrier ◽  
Free Enthalpy ◽  
Temperature Dependent ◽  
Restricted Rotation ◽  
H Nmr ◽  
Enthalpy Of Activation ◽  
End Groups ◽  
Electron Contribution ◽  
Chain Lengths

Abstract Polymethine oxonols show temperature dependent 1H-NMR-spectra because of restricted rotation of the end groups. The dependence of the value of the corresponding free enthalpy of activation AGt on the length of the poly-methine chain can be explained by the change of the π-electron contribution to ⊿G≠.

Chlormethylchlorphosphane mit sperrigen Substituenten -Synthese und reduktive Enthalogenierung mit Fe2(CO)9 / Bulky Chloromethylchlorophosphines -Syntheses and Reductive Dehalogenation with Fe2 (CO)9

1997 ◽  
Vol 52 (8) ◽  
pp. 883-894 ◽  
Author(s):  
Jörg Fischer ◽  
Peter Machnitzki ◽  
Othmar Stelzer
Keyword(s):  
Nmr Spectra ◽  
Elevated Temperatures ◽  
Reductive Dehalogenation ◽  
Molar Ratio ◽  
Carbonyl Complex ◽  
Temperature Dependent ◽  
Phenyl Derivative ◽  
H Nmr ◽  
Halogen Exchange ◽  
Stage Synthesis

Chloromethylchlorophosphines R(Cl)P-CH2-Cl (R = C6H11, sec-C4H9, 2,4,6-R′3C6H2; R′ = tBu, iPr) with bulky substituents (1a - 1d) have been prepared by treatment of Cl2P-CH2-Cl with organolithium compounds RLi (R = 2,4,6-R′3C6H2) or Grignard reagents RMgX (R = C6H11, sec-C4H9). For the less bulky phenyl derivative Ph(Cl)P-CH2-Cl (1i) a protected group two stage synthesis has been developed employing Et2N(Cl)P-CH2-Cl as an intermediate. Si-N cleavage reactions between Cl2P-CH2-Cl and R2N-SiMe3 or nucleophilic substitution with Ph2NH yield the amino derivatives R′2N(Cl)P-CH2-Cl (R′ = Ph, Et, iPr) (1e, 1g, 1h). The chloromethylbromophosphines R(Br)P-CH2-Cl (R = Br, C6H11) have been obtained by halogen exchange in 1 and 1a with MgBr2 etherate. 1a, 1e, 1g and 1h exist preferably in an antiperiplanar conformation with respect to the P-C(H2) bond as inferred from the analysis of the 1H(CH2)-NMR spectra. Temperature dependent 1H and 13C {1H} NMR spectra indicate restricted rotational processes in 1h. On reaction of 2a with Fe2(CO)9 the η2,μ3-phosphaalkene cluster 3 is obtained, while with 2b (R = 2,4,6-iPr3C6H2) the μ3-phosphinidene cluster 4 is formed. Reductive dehalogenation of 1c (R = 2,4,6-tBu3C6H2) affords the phosphaalkene complex 6 in addition to the 2,3-dihydrobenzo[b]phosphole complex 5. Treatment of the iron carbonyl complex 7c with Fe2(CO)9 in a 1:1 molar ratio at elevated temperatures leads to a novel μ2-phosphido complex 7b with an ortho-metallated Ph2N substituent.

Zum ambidenten Charakter des Cyanotrihydroborat-Liganden in Uran(IV)-Organylen / On the Ambident Nature of the Cyanotrihydroborate Ligand in Organouranium(IV) Complexes

1983 ◽  
Vol 38 (11) ◽  
pp. 1369-1374 ◽  
Author(s):  
R. Dieter Fischer ◽  
Kenan Yünlü
Keyword(s):  
Solid State ◽  
Nmr Spectra ◽  
Colour Change ◽  
Metal Coordination ◽  
Temperature Dependent ◽  
H Nmr ◽  
Trigonal Bipyramidal ◽  
Oligomeric Complex

Both the acceptedly oligomeric complex [(C5H5)3U(μ-NCBH3)]n (1) and its hitherto unknown, appreciably more soluble and volatile homologue, [(CH3C5H4)3U(μ-NCBH3)]n (2), display NIR/VIS spectra typical of trigonal bipyramidal (tbp) metal coordination in the solid state, but of pseudotetrahedral (ψ-Td) coordination e.g. in CH2CI2 and C6H5CH3 solution. The 1H NMR spectra of 2 in these non coordinating solvents can be best explained in terms of temperature dependent equilibria involving the two rapidly interconverting ψ-Td-isomers (CH3C5H4)3U(η3-H3BCN) and (CH3C5H4)3UNCBH3. A reversible colour change: green ⇋ brown at 130-150 °C also suggests the facile rupture of U-H and U-N bonds, respectively, in thermally excited, polycrystalline (2).

scholarly journals Stickstoffverbindungen von Elementen der dritten Hauptgruppe mit intra- und intermolekularen Donor-Akzeptor-Bindungen, V [1]. Spezielle Gallium- und Indiumamide mit Alkoxogruppen / Nitrogen Compounds of Elements of the Third Main Group with Intra- and Intermolecular Donor Acceptor Bonds, V [1]. Special Gallium and Indium Amides with Alkoxo Groups

1988 ◽  
Vol 43 (5) ◽  
pp. 505-512 ◽  
Author(s):  
M. Veith ◽  
J. Pöhlmann
Keyword(s):  
Metal Atom ◽  
Nmr Spectra ◽  
Main Group ◽  
Nitrogen Compounds ◽  
Temperature Dependent ◽  
H Nmr ◽  
The Third ◽  
Donor Acceptor ◽  
Molecular Compounds ◽  
Chelating Effect

AbstractThe lithium alkoxoamidosilane (Me2Si(OtBu)(NtBu)Li)2 (4) and its trimethyltin derivative Me2Si(OtBu)(NtBu)SnMe3 (7) have been used, to introduce the ligand Me2Si(OtBu)(NtBu) = L into molecular compounds of gallium and indium. The following molecules were synthesized: L-M(Me)Cl (M = Ga (5), In (6)), L-InMe2 (8), L-InX2 (X = Cl (9), Br (10)), L2InX (X = Cl (11), Br (12)) and L2Ga2Cl2 (22). The ligand L is assumed to chelate the metal atom on the basis of temperature dependent 1H NMR spectra. The chelating effect is more pronounced in the gallium derivatives than in the indium analogues. Equilibria between L2InX/InX3 and LInX2 have been observed in diethylether solutions. No metal(I) derivatives LGa or LIn could be isolated. L2Ga2Cl2 (22), formally containing gallium(ll), can be sublimed without decomposition at 110 °C in vacuo.

scholarly journals Preparation and Characterization of Styrene Bearing Diethanolamine Side Group, Styrene Copolymer Systems, and Their Metal Complexes

2018 ◽  
Vol 2018 ◽  
pp. 1-15 ◽  
Author(s):  
Aslışah Açıkses ◽  
Necmittin Çömez ◽  
Fatih Biryan
Keyword(s):  
Free Radical ◽  
Electrical Properties ◽  
Metal Complexes ◽  
Nmr Spectra ◽  
Side Group ◽  
Conductivity Measurements ◽  
H Nmr ◽  
Ft Ir ◽  
Polymerization Method

The two copolymer systems of styrene bearing diethanol amine side group and styrene were prepared by free radical polymerization method at 60°C in presence of 1,4-dioxane as solvent and AIBN as initiator. Their metal complexes were prepared by reaction of the copolymer used as ligand P(DEAMSt-co-St)L′′ and Ni(II) and Co(II) metal ions, which was carried out in presence of ethanol and NaOH at 65°C for 48 h in pH = 7.5. The structures of the copolymers used as ligand and metal complexes were identified by FT-IR, 1H-NMR spectra, and elemental analysis. The properties of the copolymers used as ligand and metal complexes were characterized by SEM-EDX, AAS, DSC, TGA, and DTA techniques. Then, the electrical properties of the copolymers and metal complexes were examined as a function of the temperature and frequency, and the activation energies (Ea) were estimated with conductivity measurements.

Gehinderte Ligandenbewegungen in Übergangsmetallkomplexen, X1 Carbonyl-donorligand-η-1.3.5-cycloheptatrien-chrom(0)-Komplexe / Hindered Ligand Motions in Transition Metal Complexes, X1 Carbonyl-donorligand-η-1,3,5-cycloheptatriene-chromium(0) Complexes

1976 ◽  
Vol 31 (9) ◽  
pp. 1238-1247 ◽  
Author(s):  
Mahmud Djazayeri ◽  
Cornelius G. Kreiter ◽  
Hans M. Kurz ◽  
Mehrfar Lang ◽  
Saim Özkar
Keyword(s):  
Transition Metal ◽  
Metal Complexes ◽  
Transition Metal Complexes ◽  
Nmr Spectra ◽  
Temperature Dependent ◽  
Energy Barriers

Tricarbonyl-η-1,3,5-cycloheptatriene-chromium(0) (1) reacts photochemically with trimethyl-phosphine, -arsine, or -phosphite respectively to form the complexes CrC7H8(CO)2L (2-4) (L = P(CH3)3, As(CH3)3, P(OCH3)3) and CrC7H8(CO)[P(OCH3)3]2 (5) The 1H, 13C and 31P NMR spectra of these complexes are temperature dependent as a result of a hindered motion of the C7H8 ligand. By this motion the dissimilar stereoisomers of the complexes, which are present, partly in very different concentrations, are interconverted. The energy barriers of the isomerisations were determined.

Metal Complexes of Biologically Important Ligands, CLXIX [1]. Palladium(II) and Platinum(II) N,O-Chelate Complexes (R3P)(Cl)M(α-aminoacidate) with the Anions of Serine, Threonine, 3,4-Dehydroproline and 4-Hydroxyproline

2008 ◽  
Vol 63 (2) ◽  
pp. 124-128 ◽  
Author(s):  
Elfriede Schuhmann ◽  
Wolfgang Beck
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Metal Complexes ◽  
Nmr Spectra ◽  
Palladium Complexes ◽  
Chelate Complexes ◽  
Potassium Salts ◽  
Single Isomer ◽  
C Nmr

The N,O-chelates M(3,4-dehydro-D,L-prolinate)2 (M = Ni, Cu) have been obtained from Ni(OH)2 or Cu(OH)2 and the amino acid. The complexes (R3P)(Cl)M(α-aminoacidate) (M= Pd, Pt) have been synthesized from the chloro bridged compounds (R3P)(Cl)M(μ-Cl)2M(PR3)Cl (M = Pd, Pt; R = Et, n-Bu, Ph) and the potassium salts of the α-amino acids D,L-serine, D,L-threonine, 3,4-dehydro-D,Lproline and 4-hydroxy-L-proline. According to the 31P NMR and 13C NMR spectra the complexes with serinate and threoninate are formed as mixtures of cis/trans N-M-P isomers, whereas for the palladium complexes with 3,4-dehydroprolinate and 4-hydroxyprolinate a single isomer is observed

Heterobimetallic catechol-phosphine complexes with palladium and a group-13 element: structural flexibility and dynamics

2014 ◽  
Vol 43 (23) ◽  
pp. 8911-8920 ◽  
Author(s):  
G. Bauer ◽  
M. Nieger ◽  
D. Gudat
Keyword(s):  
Relative Stability ◽  
Structural Flexibility ◽  
Nmr Studies ◽  
Proton Mobility ◽  
Group 13 ◽  
H Nmr ◽  
Phosphine Complexes ◽  
Insight Into

Condensation of a catechol phosphine Pd complex [Pd(catphosH)2] with group-13 element acetylacetonates yields complexes [M(L)n(catphos)2Pd] or [M{(catphos)2Pd}2]H (M = Al, Ga, In) whose relative stability is controlled by the size of the group-13 element. 1H NMR studies give insight into the proton mobility in a Pd2In complex.

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