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1.
A series of novel phosphaalkenes, YoshPCHP(X)R (Yosh = 2,4,6-tBu3C6H2) has been prepared, as well as the first stable carbodiphosphane, YoshPCPYosh, which has been characterized by elemental analysis, NMR and mass spectroscopy.  相似文献   

2.
Ylide complexes of the type [(C6H5)3PCHRMCHRP(C6H5)3]Cl (M = Cu, Ag) have been obtained from the reaction of methylene, ethylidene- and isobutylidene-triphenylphosphorane with CuCl and AgCl. These organocopper and organosilver compounds are of surprisingly high thermal stability. In the 1H, 13C and 31P NMR spectra of the silver compound (R = H) the spin—spin interactions 1HC107,109 Ag, 31PC107,109 Ag, and for the first time, 13C107,109 Ag could be detected.  相似文献   

3.
By means of the addition of the PH-functional methylenebisphosphanes R1R2-PCH2PR3H (PCP) to the MoMo triple bond in (η5-C5H5)2Mo2(CO)4(MoMo) the complexes (η5-C5H5)2Mo2(CO)4(PCP) containing a five-membered ring system Mo2P2C are obtained. Starting with unsymmetrically substituted methylenebisphosphanes R′2PCH2PRH only one isomer is formed, while the disecondary derivatives RHPCH2PHR (as the diastereomeric mixture) gave two isomers of (η5-C5H5)2Mo2(CO)4(PCP) (A2 and AB) as indicated by the 31P{1H} and 13C{1H} NMR spectra.X-ray structural analysis of the derivative of the racemate of t-BuHPCH2PH(t-Bu) space group C2/c, monoclinic, a 18.034(2), b 14.909(1), c 11.106(1) Å, α 90, β 99.788(8), γ 90°) reveals a puckered Mo2P2C five-membered ring system (dihedral angle PMoMo′P′ 54.4(2)°) with square-pyramidal coordination geometry at the Mo atoms. Two of the CO ligands (C(6)O(1) and C(6′)O(1′)) are almost coplanar with the molybdenum atoms, while the terminal CO groups (C(7)O(2) and C(7′)O(2′)) are about orthogonal (dihedral angle C(7)MoMo′C(7′) 88.4(3), MoMo′ 3.2109(4), MoP 2.4567(8), PC(8) 1.834(3), PH(P) 1.37(3) Å).  相似文献   

4.
13C, 31P and 15N NMR data are reported for seven 2-substituted-N-phenyl-P,P,P-triphenylphospha-λ5-azenes taken at room temperature in acetone-d6 solutions. Ortho substituents significantly influence 13C, 31P, 15N chemical shifts and 1J(31P15N), 3J(31P13C) Couplings.  相似文献   

5.
The reaction between acrylonitrile and the RuH bond in HRu(CO)Cl(PPh3)3 results in the formation of a binuclear ruthenium(II) complex having chlorine bridges which are easily broken by sodio-derivatives of bidentate chelating ligands giving mononuclear hexacoordinated ruthenium(II) compounds. The RuC bond in these new complexes has been found to be stable towards nucleophilic reagents. The stereochemistry for these complexes has been suggested on the basis of IR, 1H and 31P NMR spectra.  相似文献   

6.
The preparation and properties are described of trans-[(Ph3P)2(CO)M(RNSNR)] [ClO4] (M  RhI, IrI; R  Me, Et, i-Pr, t-Bu) and of cis- or trans-[L2Pt(RNSNR)X] [ClO4] (X  Cl?, L  Et2S, PhMe2As, PhMe2P, R  Me, t-Bu; X  CH3, L  PhMe2P, R  Me).1H and 13C NMR data show the existence of various isomers in solution which may interconvert via intra- and inter-molecular exchange processes. A general reaction scheme for the intramolecular exchange processes is discussed.  相似文献   

7.
The 13P and 13C spectra of the triply 13C labelled molecules (CH3)3P, (CH3)3PO, (CH3)3PS and (CH3)3PSe oriented in a nematic phase are reported. The CPC bond angles have been measured. The 13P chemical shift tensor shows a large anisotropy except in the case of (CH3)3P. The abnormal large value observed for the PSe bond length suggests a large anisotropy of the 1J(PSe) spin coupling.  相似文献   

8.
《Microporous Materials》1996,5(6):365-379
The synthesis and structural characterization of oxyfluorinated microporous gallophosphates with the ULM-3 type are presented. This material is hydrothermally prepared (180°C, autogenous pressure, 24 h) by using linear diamines [H2N(CH2)3–5NH2] as templates. The structures of the phases obtained with the variable organic chain lengths were examined by single-crystal X-ray diffraction (XRD) and 31P, 19F, 13C solid-state nuclear magnetic resonance (NMR) spectroscopy. This study showed that the relative flexibility of the C3C5 diamines allows the preservation of the topology of the type ULM-3. In this series, the presence of fluorine, which is found in the bridging position between two gallium atoms, is strongly correlated to the existence of hydrogen bonds with ammonium groups of the organic molecules.  相似文献   

9.
Proton NMR data at 100 MHz are reported for thirteen para- and meta-substituted phenyltrimethyltin compounds, XC6H4Sn(CH3)3, where X = para-N(CH3)2, para-OCH3, para-OC2H5, para-CH3, meta-CH3, -H, para-F, meta-OCH3, para-Cl, para-Br, meta-F, meta-Cl and para-Sn(CH3)3. Correlation coefficients with Hammett σ-constants of greater than 0.95 are obtained with the methyltin proton chemical shifts and coupling constants to carbon [1J(13C1H)] and tin [2J(SnC1H)]. Solvent effects and other extraneous factors invalidate comparisons of ? values in terms of the relative attenuation of the transmission of substituent effects through homologous carbon, silicon, germanium and tin systems, but coupling constant data reflect a diminution of ca. one tenthfold per bond in the order ?[C(1)Sn] > ? [SnC] > ? [CH]. Satisfactory correlations (r > 0.95) are obtained in this series of closely-related compounds among the conventionally recorded two-bond, 2J(SnC1H) and the constituent, one-bond 1J (Sn13C) and J(13C1H) coupling constants, but the correlation coefficient for the comparison between the two one-bond couplings, 1J(Sn13C) and 1J(13C1H) is lower (r = 0.872). Changes in the couplings at the methyltin carbon bond tin-119 atoms are interpreted in terms of isovalent hybridization; a model based upon effective nuclear charges is tested with respect to both NMR coupling constants and 119Sn Mössbauer Isomer shifts at tin and is invalidated. Proton and carbon-13 NMR, chemical shift and coupling constant data are used to derive a Hammett σ-constant for the para-trimethyltin group of ?0.14, and the significance of this value is discussed.  相似文献   

10.
Reaction of barbituric acid (2,4,6-pyrimidinetrione) or its derivatives with LAuCl (L = triphenylphosphine) gave 3-LAu-5,5-diethyl-, 1,3-(L'Au)2-5,5-diethyl- (L′ = L or L′ = Cy3P), 1,3-dimethyl-5,5-bis(LAu)-, or 1,3,5,5-tetrakis-(LAu)barbituric acid, which were characterized as N-, N,N′-, C,C′-, or N,N′,C,C-gold derivative,s respectively, by IR, 1H, 13C and 31P NMR spectroscopy. In the case of 1,3-(LM)(L″M)-5,5-diethylbarbituric acid compounds with M = gold and L″ either Cy3P, Ph3As, or (4-tolyl)3P, or ML = ML″ = HgMe were prepared. An X-ray diffraction study of 1,3-(LAu)2-5,5-Et2-pyrimidin-2,4,6-trione · 3C6H6 revealed that (a) the heterocyclic ring is planar, (b) there is no inter- or intra-molecular Au ⋯ Au interaction, and (c) the coordination around each gold atom is approximately linear (PAuN 178.3(4)°, with AuN 2.022(12) and AuP 2.233(5) Å. The molecular parameters are compared with those for barbituric acid and other barbiturates.  相似文献   

11.
Synthesis, Raman and NMR studies are presented for the new octahedral trimetallic complexes with composition [IrCl(SnCl3)(HgCl)(CO)(PR3)2], R = p-XC6H4; X = H, CH3O, F, Cl. Only the isomer containing the Cl3SnIrHgCl fragment and trans phosphine ligands is observed. Force constants for the IrSn and IrHg bonds as well as 31P, 119Sn and 199Hg NMR data are reported. The presence of a spin-spin coupling constant of more than 40,000 Hz between the 199Hg and 119Sn atoms is shown to originate from a two-bond and not a one-bond interaction.  相似文献   

12.
Bis(fluorbenzoyloxy)methyl phosphane oxides CH3P(O)[OC(O)R]2 [R = C6H42F (1), C6H43F (2), C6H44F (3), C6H32,6F2 (4), C6H2,3,5,6F4 (5)] were prepared by treating silver salts of carboxylic acids AgOC(O)R with CH3P(O)C?2 (IR-, 1H-, 19?F-and 31P{1H}-NMR-data). The mixed anhydrides 1–5 show unusual thermal stability at room temperature. Stability against hydrolysis decreases with increasing number of fluorine-atoms. The reaction of R′P(O)C?2 [R′ = CH3, C6H5, (CH3)3C] with MIOC(O)RF [RF = CF3, C2F5, C6F5; MI = AgI, NaI T?I] was investigated.  相似文献   

13.
Phosphorus-31 NMR and X-ray crystallography show that the two similar chelating triphosphine ligands PhP(CH2CH2PPh2)2(2,2-P3) and PhP(CH2CH2CH2 PPh2)2(33-P3) form cobalt(I) complexes having trigonal-bipyramidal and square-pyramidal structures, respectively. The structures and PP coupling constants of [Co(33-P3)(P(OMe)3)CO]BF4·1THF and [Co(22-P3)(P(OMe)3)2]BF4 are given, and the change from square-pyramidal geometry in [Co(33-P3)P(OMe)3)CO]+ to trigonal-bipyramidal in [Co(22-P3)(P(OMe)3)2]+ may be rationalized in terms of a decreased “chelate bite angle” for the PhP(CH2CH2PPh2)2 ligand.  相似文献   

14.
The molecular geometry of perfluoro(methyloxirane) has been studied using gas-phase electron diffraction data, effective least-squares refinement of the structure being achieved with the aid of constraints to limit the number of variable parameters. With the CCF3 bond constrained to be 0.078 Å longer than the ring CC, the refined bond- length values CF (av.) = 1.323(2), CO (av.) = 1.410(8), and CC (ring) = 1.467(7) Å (rg values, with e.s.d. in parentheses) were obtained; the angles between ring bonds and substituent CF bonds were CCF (av.) 121(1) and OCF (av.) 114(1)o, the corresponding parameters involving the bulkier CCF3 fragment being larger by 3o in each case [∠CCCF3 124(1)o∠OCCF3 117(2)o]. The remaining refined parameters were ∠CCF(of CF3) = 110.6(4)o and τ , a torsion angle defining the orientation of the CF bonds of the CF3 group with respect to ring bonds, = 29(2)o. Dependent bond angles possessed the values 62.7 (COC), 58.7 [OCC (ring)], 108.3 [FCF (CF3 group)], 114 [FCF (ring CF2)], and 111o (FCCF3).  相似文献   

15.
195Pt, 119Sn and 31P NMR characteristics of the complexes trans-[Pt(SnCl3)(carbon ligand)(PEt3)2] (1a-1e) are reported, (carbon ligand = CH3 (1a), CH2Ph (1b), COPh (1c), C6Cl5 (1d), C6Cl4Y (e); Y = meta- and para-NO2, CF3, Br, H, CH3, OCH3, or Pt(SnCl3)(PEt3)2. The values of 1J(195Pt, 119Sn) vary from 2376 to 11895 Hz with the COPh ligand having the smallest and the C6Cl5 ligand the largest value, making a total range for this coupling constant, when the dimer syn-trans-[PtCl(SnCl3)(PEt3)]2 is included, of ca. 33000 Hz. In the meta- and para-substituted phenyl complexes 1J(195Pt, 119Sn) (a) is greater for electron-withdrawing substituents, (b) varies more for the meta-substituted derivatives (5634 to 7906 Hz) than for the para analogues (6088 to 7644 Hz) and (c) has the lowest values when the Pt(SnCl3)(PEt3)2 group is the meta- or para-substituent. The direction of the change in 1J(195Pt, 119Sn) is opposite to that found for 1J(195Pt, 119P). For the aryl complexes linear correlations are observed between δ(119Sn), 1J(195Pt, 119Sn), 1J(195Pt, 31P), 1J(119Sn, 31P) and the Hammett substituent constant σn. δ(119Sn) and 1J(195Pt, 119Sn) are related linearly to v(Pt-H) in the complexes trans-[PtH(C6H4Y)(PEt3)2]; δ(119Sn) and δ(1H) (hydride) are also linearly related. Based on 1J(195Pt, 119Sn), the acyl ligand is suggested to have a very large NMR trans influence. The differences in the NMR parameters for (1a-e) are rationalized in terms of differing σ- and π-bonding abilities of the carbon ligands.The structure of 1c has been determined by crystallographic methods. The complex has a slightly distorted square planar geometry with trans-PEt3 ligands. Relevant bond lengths (Å) and bond angles (°) are: PtSn, 2.634(1), PtP, 2.324(4) and 2.329(4), PtC, 2.05(1); PPtP, 170.7(6), SnPtC, 173.0(3), SnPtP, 92.1(1), 91.7(1), PPtC, 88.8(4) and 88.3(4). The PtSn bond separation is the longest yet observed for square-planar platinum trichlorostannate complexes, and would be consistent with a large crystallographic trans influence of the benzoyl ligand. The PtSn bond separation is shown to correlate with 1J(195Pt, 119Sn).  相似文献   

16.
The crystal structure of [(C8H12)Ir{P(OC6H3Me)(OC6H4Me)2} {P(OCH2)3CMe}] has been determined. a 18.32, b 18.98, c 9.35 Å, U 3251 Å3, Pn21a, Z = 4, R = 0.048, 2541 observed data.The coordination about the iridium atom is distorted trigonal bipyramidal; the two phosphorus atoms are equatorial, the σ-bonded carbon is axial, and the bidentate cyclooctadiene is bonded axialequatorial. The IrC(axial) bonds are longer than the IrC(equatorial) bonds: 2.22, 2.26; 2.17, 2.19 Å. The IrC(σ) bond length is 2.19 Å, not significantly different from the formally π-bonded C to Ir distances. The IrP lengths of 2.201 and 2.240 Å and the PIrP angle of 108.7° are normal. The longer IrP bond is in the five-membered chelate ring. The inertness to substitution is discussed.  相似文献   

17.
C. Broquet 《Tetrahedron》1973,29(22):3595-3598
The enolate ylide Ph3P+C?C(Ph)O?Li+ obtained by the reaction of HMPT-Li with the benzoylmethylenetriphenylphosphorane Ph3PCHCOPh reacts with aliphatic ketones, in contrast to its precursor. This condensation makes it possible to prepare β,γ-unsaturated ketones, of type RCHC(R′)CH2COPh, instead of the α,β isomer usually obtained in a Wittig reaction.  相似文献   

18.
M(CO)5X (M = Mn, Re; X = Cl, Br, I) reacts with DAB (1,4-diazabutadiene = R1N=C(R2)C(R2)′=NR′1) to give M(CO)3X(DAB). The 1H, 13C NMR and IR spectra indicate that the facial isomer is formed exclusively. A comparison of the 13C NMR spectra of M(CO)3X(DAB) (M = Mn, Re; X = Cl, Br, I; DAB = glyoxalbis-t-butylimine, glyoxyalbisisopropylimine) and the related M(CO)4DAB complexes (M = Cr, Mo, W) with Fe(CO)3DAB complexes shows that the charge density on the ligands is comparable in both types of d6 metal complexes but is slightly different in the Fe-d8 complexes. The effect of the DAB substituents on the carbonyl stretching frequencies is in agreement with the A′(cis) > A″ (cis) > A′(trans) band ordering.Mn(CO)3Cl(t-BuNCHCHNt-Bu) reacts with AgBF4 under a CO atmosphere yielding [Mn(CO)4(t-BuNCHCHN-t-Bu)]BF4. The cationic complex is isoelectronic with M(CO)4(t-BuNCHCHNt-Bu) (M = Cr, Mo, W).  相似文献   

19.
Nitriles react with PF5 and also with AsF5, SbF5 forming 1:1-adducts. Using C2Cl3F3 as a solvent is of advantage for this reaction. PF5·CH3CN and [N(C2H5)4]SH give [N(C2H5)4][P2S2F8] with a sulfur double bridge and hexafluorophosphate in acetonitrile [1]. In case of AsF5·CH3CN a salt with the anion [AsF5NHCSCH3]? has been isolated [2]. Following products have been confirmed in a reaction mixture of PF5·CH3CN and SH? in acetonitrile by NMR (31P and 19F): [PF6]?, [F5PSPF5]2?,
, F4PSH, F3PS, HPS2F2, [PS2F2]?, [F5PNC(SH)CH3]?, [F5PNHCSCH3]?, [F5PSH]?. With a ratio PF5·CH3CN: SH? = 2:1 the S-bridge-complexes are prefered whereas in case of a ratio 1:1 the non-bridged P-complexes are the main products.  相似文献   

20.
β-ketonitriles R1COCH2CN and R1COCH(R2)CN are respectively prepared from (CH3)3SiOCOCHLiCN or R2CHLiCN by acylation reaction with mixed anhydrides RCOOCO2Et.  相似文献   

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