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1.
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 Cs 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.  相似文献   

2.
The collision-induced dissociation (CID) spectra of five alkylmethyleneimmonium ions (H2C-N+R1R2, (a) R1 = R2 = C2H5, (b) R1 = n-C3H7, R2 = H, (c) R1 = n-C3H7, R2 = CH3, (d) R1 = n-C3H7, R2 = C2H5, (e) R1 = R2 = n-C3H7) are reported and discussed in terms of the mechanism of alkane loss. The most abundant alkane losses result from 2-azaallylic bond cleavages within R1 and R2 leading to daughter ions of m/z 84. Ion d (R1 = n-C3H7, R2 = C2H5) was chosen for a deuterium-labelling study because it exhibited methane loss nearly free from interferences with other fragmentations. The methane lost consists to a great extent (95%) of the methyl moiety of R2. Whereas the methyl moiety obviously stays intact during the fragmentation process, the hydrogen additionally needed originates from all positions of R1 and the double-bonded methylene in an approximately random distribution, suggesting extensive hydrogen migrations preceding the transfer step.  相似文献   

3.
The complexes of trans-[Co(III)(R,CH3-dioxH)2(py)2]I2 (R = CH3, C2H5, n-C3H7 and n-C4H9) were investigated in solution by 1H and 13C NMR spectra and 13C spin-lattice relaxation time measurements. The 1H and 13C-resonances of the R = C2H5, n-C3H7 and n-C4H9) groups were shifted to higher field than those of the free ligands by the complexation; it was attributable to the ring current shielding due to the axial pyridine ligands of the complexes. 13C spin-lattice relaxation times were interpreted as due to movement of the axial pyridine ligands as if they twist around the CoN (pyridine nitrogen) bond axis and the above R groups were moving segmentally. These segmental movements allowed the R groups to approach closely toward the axial pyridine ring plane to experience the ring current shielding.  相似文献   

4.
The X-ray-crystal structures of both (η5-C5H5)Cr(CO)2(NO) (I) and (η5-C13H9)Cr(CO)2(NO) (II, η5-C13H9 = η5-9H-fluorenyl) are described. I crystallizes in the monoclinic space group P21/n with lattice constants a 10.998(4), b 7.066(3), c 11.940(4) Å, β 116.37(4)°, and ?calc 1.63 g cm?3 for Z = 4. II belongs to the orthorhombic space group Pnma with a 6.463(4), b 15.512(6), c 12.916(6) Å, and ?calc 1.55 g cm?3 for Z = 4. Least-squares refinement gave final conventional R values of 0.037 based on 1081 independent observed reflections for I, and 0.042 with 630 reflections for II. The carbonyl and nitrosyl groups are disordered in I, but the nitrosyl ligand in II occupies a position “trans” to the electron-rich C(9) of the fluorenyl system. Photolysis of II in liquid olefins (L) or acetyleness leads to substituted derivatives of the type (η5-C13H9)Cr(CO)(NO)L (L = cyclooctene, cycloocta-1,5-diene, norbornene, norbornadiene, phenylacetylene).  相似文献   

5.
The preparations and properties are described of novel anionic and neutral mononuclear biimidazolate (biim), bibenzimidazolate (bibzim), or tetramethylbiimidazolate (tmbiim) manganese(I) and molybdenum(II) complexes of the type [Et4N][Mn(CO)2L2(bibzim)] (L = P(OEt)3); [Et4N][Mo(η5-C5H5)(CO)2-(N)2] ((N)22− = biim2−, bibzim2− tmbiim2−); [Mn(CO)4−nLn{H(N)2}] (n = 1; H(N)2 Hbibzim; L = P(OMe)3, PEt3), (n = 2; H(N)2 = Hbiim, Hbibzim; L = P(OPh)3, P(OMe)3, P(OEt)3, P(OiPr)3; [Mo(η5-C5H5)(CO)2{H(N)2}] (H(NN)2 = Hbiim, Hbibzim, Htmbiim, in which the heterocyclic anions act as bidentate chelate groups. Treatment of the anionic complexes with MeI gives neutral derivatives of general formula [Mn(CO)2L2(Mebibzim)] (L = P(OMe)3, P(OEt)3) and [Mo(η5-C5H5)(CO)2{Me(N)2}] (Me(N)2 = Me-biim, Mebibzim, Metmbiim. Cationic manganese(I) complexes of the type [Mn(CO)4−nLn{H2(N)2}][ClO4 (n = 1; H2 (N)2 = H2bibzim; L = P(Ome)3, PEt3), (n = 2; H2(N)2 = H2biim, H2bibzim; L = P(OPh)3, P(OMe)3, P(OEt)3, P(OiPr)3) have also been obtained by treating the corresponding neutral complexes with HClO4. The structures of the complexes have been elucidated by molecular weight determinations, conductance data, and IR spectroscopy.  相似文献   

6.
The treatment of the aquocation [Co(η3-2-MeC3H4)(η5-C5H5)(H2O]+ with neutral and anionic ligands gives new cobalt complexes containing cations [Co(η3-2-MeC3H4)(η5-C5H5)L]n+, n = 0; L = CN, CH3COO, CF3COO and n = 1; L = P(p-MePh)3, NCEt, NCPh, CNCy, dppm and [{Co(η3-2-MeC3H4)(η5-C5H5)}2 (μ-L-L)]2+, L-L = bipy, dppm. The neutral cyano complex reacts with various electrophiles to give cationic isocyanide complexes containing the cation [Co(η3-2-MeC3H4)(η5-C5H5)(CNR)]+, which have been isolated in low yields. Chemical behaviour and structural implications of IR and 1H and 13C NMR spectra are discussed.  相似文献   

7.
《Tetrahedron: Asymmetry》1998,9(23):4219-4238
A wide variety of planar chiral cyclopalladated compounds of general formulae [Pd{[(η5-C5H3)–CHN–CH(Me)–C10H7]Fe(η5-C5H5)}Cl(L)] (with L=py-d5 or PPh3), [Pd{[(η5-C5H3)–CHN–CH(Me)–C10H7]Fe(η5-C5H5)}(acac)] or [Pd{[(R1–CC–R2)25-C5H3)–CHN–CH(Me)–C10H7]Fe(η5-C5H5)}Cl] (with R1=R2=Et; R1=Me, R2=Ph; R1=H, R2=Ph; R1=R2=Ph; R1=R2=CO2Me or R1=CO2Et, R2=Ph) are reported. The diastereomers {(Rp,R) and (Sp,R)} of these compounds have been isolated by either column chromatography or fractional crystallization. The free ligand (R)-(+)-[{(η5-C5H4)–CHN–CH(Me)–C10H7}Fe(η5–C5H5)] (1) and compound (+)-(Rp,R)-[Pd{[(Et–CC–Et)25-C5H3)–CHN–CH(Me)–C10H7]Fe(η5-C5H5)}Cl] (7a) have also been characterized by X-ray diffraction. Electrochemical studies based on cyclic voltammetries of all the compounds are also reported.  相似文献   

8.
《Comptes Rendus Chimie》2002,5(4):319-324
The ligand substitution by diphosphine L–L on (η5-C5H5)Fe(CO)2I usually results in the chelated 〚(η5-C5H5)Fe(CO)(η2-L–L)+〛〚I〛 product exclusively. One could suppress the chelated complexes and selectively prepare the bridged 〚{(η5-C5H5)Fe(CO)2}2(μ-L–L)2+〛 complexes by application of the electron-transfer chain catalysis with a chemical initiation. Introducing a catalytic amount of reductant at low temperature to the mixture of 2:1 (η5-C5H5)Fe(CO)2I/L–L in THF selectively produces the bridged complexes in 78–93% isolated yields where L–L is Ph2P(CH2)nPPh2, n = 1–4, or (η5-C5H4PPh2)2Fe.  相似文献   

9.
The thiosemicarbazone derivatives R1-C6H4-CH=N-N=(C-S-R2)-NH-R3 [R1 = H, OH; R2 = H, Ph; R3 = C2H5, C3H5] were prepared by a modified general method. The Pd(II) complexes of the thiosemicarbazone ligands LI–VI were isolated in the compositions [Pd(L)Cl2], [Pd(L)Cl] and [Pd(L)2]. The 1: 1 and 1: 2 metal complexes have non-ionic character, and the compounds were characterized by analytical data and infrared and proton resonance spectroscopy. The cis-trans and syn-anti isomers of the thiosemicarbazones were determined by means of 1H NMR, and the coordination behavior of the polydentate thiosemicarbazone ligands towards the palladium ion were discussed.  相似文献   

10.
The reaction between [Au(o-C6H4NO2)Cl] and tetrahydrothiophene (tht) in the presence of NaClO4 give a solution (probably containing [Au(o-C6H4NO2)(tht)]) that can be used to prepare neutral [Au(o-C6H4NO2)Ln] (L = AsPh3, n = 1; L = SbPh3, n = 2; L = 1,10-phenanthroline, n = 1) or anionic [Au(o-C6H4-NO2(CN)] complexes. Treatment of [Au(o-C6H4NO2)(PPh3)] with chlorine or PhICl2 gives trans- or cis-[Au(o-C6H4NO2)Cl2(PPh3)]. Isomerizations occur when the cis-isomer is treated with concentrated solutions of chlorine or when the trans-isomer is heated.An X-ray diffraction study of [Au(o-C6H4NO2)(AsPh3)] has revealed an almost linear coordination around the gold atom (AsAuC mean value 177(2)°). The AuO distance is too long (mean value 2.80(3) Å) for intramolecular coordination.  相似文献   

11.
The study of perfluoroalkyl metal complexes is key to understand and improve metal-promoted perfluoroalkylation reactions. Herein, we report the synthesis of the first gold complexes with primary or secondary perfluoroalkyl ligands by photoinitiated reactions between AuI organometallic complexes and iodoperfluoroalkanes. Complexes of the types LAuRF (L=PPh3 or N,N-bis(2,6-diisopropylphenyl)imidazol-2-ylidene; RF=n-C4F9, n-C6F13, i-C3F7, c-C6F11) and [Au(RF)(Ar)I(PPh3)] (Ar=2,4,6-trimethylphenyl) have been isolated and characterized. Alkynes RFC≡CR were formed by reaction of Ph3PAuC≡CR (R=Ph, nHex) with IRF (RF=n-C4F9, i-C3F7). According to the evidences obtained, this transformation undergoes through a photoinitiated radical mechanism. AuIII complexes [Au(n-C4F9)(X)(Y)L] (X=Y=Cl, Br, I, Me; X=Me, Y=I) have been prepared or in situ generated, and their thermal or photochemical decomposition reactions have been studied.  相似文献   

12.
The Cu(II) and Co(II) complexes with 3,5-diphenyl-4-amino-1,2,4-triazole (L) of the composition CuLA2 · H2O (A = Cl?, Br?), CuL2A2 (A = Cl?, Br?, NO 3 ? ), CoL2A2 · nH2O (A = Cl?, n = 1; A = NCS?, n = 0) are synthesized. In these complexes, the ligand L is coordinated to a metal in monodentate mode through the heterocyclic N(1) atom. The Cu: L = 1: 1 complexes have binuclear structures with the anions acting as bridges, whereas the M: L = 1: 2 complexes are mononuclear. Both ferro-and antiferromagnetic exchange interactions are detected for the synthesized complexes.  相似文献   

13.
Photo-reaction between the ligands Ph2ECH2EPh2 (E = P: dppm, E = As: dpam, E = Sb: dpsm), L, and the vanadium complexes η5-C5H5V(CO)4 and [Et4N][V(CO)6] yields monosubstituted mononuclear (dpsm) and dinuclear, ligand-bridged complexes (dpam, dpsm). With dppm, the final products are disubstituted chelate complexes, but monosubstituted mono- and dinuclear species are formed as intermediates.The shielding of the 51V nucleus decreases in the series dpsm > dppm > dpam and {M(CO)n} > {M(CO)n?1} L > {M(CO)n?1}2μ-L > {M(CO)n?2}dppm ({M(CO)n}[V(CO)6]?, η5-C5H5V(CO)4). The half-widths of the NMR signals are greater for dinuclear than for mononuclear complexes.The crystal and molecular structures of η5-C5H5V(CO)3As2Ph4 have been determined. The compound crystallizes in the space group P21/c with a = 1347.8, b = 1020.0, c = 2085.2 pm and β = 82.3°. Due to steric crowding, the 51V shielding is low composed to that of {η5-C5H5V(CO)3}2μ-dpam.  相似文献   

14.
New η3-allyldimethyl complexes Ru(η5-C5R5)(η3-C3H5)(CH3)2, where R = H or CH3, are prepared from Ru(η5-C5R5)(η3-C3H5)Br2 by alkylation with trimethyl-aluminium. The RuIV dimethyl complex is thermally converted to the RuII 1-methylallyl compound, Ru(η5-C5R5)(η3-CH2CHCHCH3)L, where L = CO or t-C4H9NC, with evolution of methane. Kinetic and deuteration studies on the reductive process are also discussed.  相似文献   

15.
The complex compound [CdL1.25(CH3CO2)2(H2O)], where L = NH2-C6H4-C(CH3)2-C6H4-C(CH3)2-C6H4-NH2 was synthesized and its crystal structure was determined. The crystals are triclinic, space group P $ \bar 1 $ , a = 10.160(1) ?,b = 17.442(1) ?, c = 20.232(1) ?, ?? = 67.93(1)°, ?? = 87.22(1)°, ?? = 77.65(1)°, V = 3340.2(4) ?3, ??calc = 1.392 g/cm3, Z = 4. The structure contains two crystallographically non-equivalent Cd2+ ions, each coordinating two nitrogen atoms of two ligands L, four oxygen atoms of two bidentate acetate groups, and one water molecule. The coordination polyhedron of Cd2+ ions is anirregular sevenvertex polyhedron. The interaction of cadmium with ligands L gives rise to centrosymmetric tetranuclear complexes [Cd4L5].  相似文献   

16.
Mixed chloride dialkyldithiophosphates of arsenic(III) and antimony(III), [(RO)2PSS]nMCl3?n (M = As, Sb; n = 1, 2; R = C2H5, n-C3H7, i-C3H7 and i-C4H9) have been synthesized for the first time by the reac metal chlorides with sodium dialkyldithiophosphates or alternatively by co-disproportionation reactions of metal chlorides with metal tris(dialkyldithiophosphates) in different stoichiometric ratios. Mixed halide dialkyl-dithiophosphates of antimony(III) have also been prepared by the cleavage reactions of antimony tris(diisopropyldithiophosphate) with bromine or iodine. Hydrolysis reactions of a few of these compounds have also been studied. The new compounds have been characterized by elemental analyses, molecular weight determinations (cryoscopic) as well as IR and NMR (1H, 31P) data; chelated structures with bidentate dialkyldithiophosphate groups are proposed.  相似文献   

17.
The reactivity of the cationic vinylidene complexes [Fe{CC(R1)R2}(η-C5H5(dppm)]+ toward different nucleophiles has been investigated. Whereas the disubstituted complexes (R1 = Me; R2 = Ph or tBu) are unreactive with water and methanol, the addition of the anion hydride proceeds stereoselectively to give the alkenyl E isomers. The structure of (E)-[Fe{C(H)C(Me)Ph}(η-C5H5(dppm)] has been determined by an X-ray diffraction study. Nucleophilic additions to the unsubstituted complex (R1 = R2 = H) have also been examined.  相似文献   

18.
Treatment of [BzPh3P][AuCl2] with [Hg(x-C6H4NO2)2] (x = o, m, or p) gives anionic gold(I) complexes of the type [BzPh3P][Au(R)Cl](R = o-, m- or p-C6H4NO2, Bz = C6H5CH2). The chloro ligand in [Au(o-C6H4NO2)Cl]? can be replaced by bromo or iodo ligands by use of NaBr or NaI. The anions [Au(R)Cl]? react with neutral monodentate ligands, L, to give neutral mononuclear complexes [Au(R)L] (R = o-C6H4NO2, L = PPh3, AsPh3; R = m-C6H4NO2, L = PPh3) and with 1,2-bis(diphenylphosphino)ethane (dpe) to give [Au2(R)2(dpe)] (R = o-C6H4NO2). The corresponding [Au(p-C6H4NO2)Cl]? reacts with PPh3 or AsPh3 to give mixtures containing [AuClL]. The anionic ortho-nitrophenylgold(I) complex is much more stable than its meta- or para-nitrophenyl isomers. These are thought to be the first reports of nitrophenylgold(I) complexes.  相似文献   

19.
Extraction capability and selectivity of acetyl-containing phosphine oxides R2P(O)CMe2CH2C(O)Me (R = Pr, Bu, n-C5H11, n-C6H13, n-C8H17, Ph) toward actinides (UVI, ThIV) and trivalent lanthanides (LaIII, NdIII, HoIII, YbIII) were studied. The new ligands were shown to be more efficient and selective in the extraction of uranium, thorium, and heavy lanthanides from nitric acid solutions into chloroform as compared to the known extractants such as carbamoylphosphine oxide Ph2P(O)CH2C(O)NBu2, trioctylphosphine oxide (n-C8H17)3P(O), and tributyl phosphate (n-BuO)3P(O).  相似文献   

20.
The reaction of dicarbonyl- and carbonyl(trimethylphosphine)(cyclopentadienyl)-carbyne complexes of molybdenum and tungsten η5-C5H5(CO)2−n(PMe3)nMCR (n = 0, 1; M = Mo, W; R = CH3, C6H5, C6H4CH3, C3H5) with protic nucleophiles HX (X = Cl, CF3COO, CCl3COO) leads, through a combined protonation/carbon-carbon coupling reaction, to η2-acyl complexes η5-C5H5(CO)1−nX2(PMe3)n-M(η2-COCH2R). The reaction conditions, the results of the spectroscopic measurements and the X-ray structure of η5-C5H5(CO)(Cl2)W(η2-COCH2CH3) are reported.  相似文献   

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