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1.
Pablo Espinet Paloma Gomez-Elipe Fernando Villafae 《Journal of organometallic chemistry》1993,450(1-2):145-150
The first carbonyl molybdenum-(O) and -(II) complexes with phenylbis(2-pyridyl)phosphine (PPhpy2) have been synthesized. PPhpy2 reacts with [Mo(CO)5(NCMe)] to give [Mo(CO)5(PPhpy2-P)]. With [Mo(CO)4(NBD)] (NBD = norbornadiene) it gives [Mo(CO)4(PPhpy2-P)2] when a 2 : 1 ratio is used, or [MO(CO)4(py2PhP---N,N′)] for a 1 : 1 ratio. Decarbonylation of any of these pyridylphosphine complexes leads to an oligomer of formula {MO(CO)3(μ-PPhpy2)}n, which is also obtained after heating [MO(CO)6] in solution with an equimolar amount of PPhpy2. The oligomer undergoes oxidative addition by iodine or allylbromide to give [MoI2(CO)3(py2PhP---N,N′)], or [MoBr(η3-CH2CHCH2)(CO)2(py2PhP---N,N′)], respectively. These complexes are also obtained by addition of equimolar amounts of PPhpy2 to solutions of [MoI2(CO)3(NCMe)2] and MoBr(η3-CH2CH CH2)(CO)2(NCMe)2, respectively. The ligand tends to act as a P-donor towards molybdenum(O) substrates, and as a chelating N,N′-donor in molybdenum (II) complexes. 相似文献
2.
Robert Toreki Richard R. Schrock William M. Davis 《Journal of organometallic chemistry》1996,520(1-2):69-78
Photolysis of compounds of the type [Re(CCMe2R)(OR′)2] (R = Me or Ph; OR′ = O′Bu, OCMe2(CF3), or OCMe(CF3)2) in benzene with a medium pressure mercury lamp yields compounds of the type [Re(OR′)2]2(μ-CCMe2R)2 in an intramolecular and irreversible manner. [Re(CCMe2R)(OR′)2]2 and [Re(OR′)2]2(μ-CCMe2R)2 (OR′ = O′Bu or OCMe2(CF3)2) both react with excess carbon monoxide in several solvents to afford the dimers [Re(OR′)2(CO)]2(μ-CCMe2R)2 quantitatively. An X-ray study of [Re(OtBu)2(CO)]2 (μ-CtBu)2 shows it to consist of two distorted trigonal bipyramids connected by two symmetrically bridging neopentylidyne ligands. The unbridged dimers of general formula [Re(CCMe2R)(OR′)2]2 do not react readily with simple substrates such as phosphines, olefins, or acetylenes, although [Re(CCMe2R)(OtBu)2]2 can be oxidized by iodine to yield Re(CCMe2R)(OtBu)2I2 in good yield. In contrast, {Re[OCMe(CF3)2]2}2(μ-CtBu)2 reacts with one equivalent of phenylacetylene to give a species in which one of the two bridging alkylidyne ligands is retained. 相似文献
3.
Reductive dehalogenation of the (chloro)(phenylethynyl)phosphine (2,4,6-tBu3C6H2O)(PhCC)PCl, I, by Co2(CO)8, II, yields the neutral phosphenium ion complex [(R)(R′)]P=Co(CO)3, III, (R = 2,4,6-tBu3C6H2O; R′ = (η2-C≡CPh)Co2(CO)6), which contains a trigonally planar coordinated phosphorus atom. When NaCo(CO)4, V, is used instead of II a dinuclear complex, Co2(CO)6[μ2-P(R)(R′)]2, VI, (R = 2,4,6-tBu3C6H2O; R′ = C≡CPh) is formed in which the phosphido ligands P(R)(R′), bridge in a μ2 fashion two Co(CO)3 units. The mechanism of formation of VI, involving a formal dimerization of two [(2,4,6-tBu3C6H2O)(PhC≡C)]P=Co(CO)3 fragments, is discussed. However, (tBu)(PhC≡C)PCl, VII, reacts with II, to yield the cluster compound VIII, containing the two μ2-bridging units (tBu)[(η2-C≡CPh)Co2(CO)5]P and (tBu)(PhC≡C)P.
Compounds II and VI–VIII were identified from their analytical and spectroscopic (IR, 1H-, 13C- and 31P-NMR) data. The molecular structure of the cluster compound VIII was determined by an X-ray diffraction study. 相似文献
4.
Leopoldo Contreras Antonio Pizzano Luis S nchez Ernesto Carmona 《Journal of organometallic chemistry》1995,500(1-2):61-67
The following structural peculiarities of the agostic acyl structure
2R) (R = H, SiMe3) and some characteristic chemical reactivity of the M-η2-acyl and iminoacyl linkage are described. (i) A structural comparison of the bonding parameters within three agostic acetyl Mo complexes containing the dithioacid ligand, indicates that the agostic interaction strengthens upon increasing the electron-releasing properties of the S-chelating ligand. (ii) The acyl-xanthate complex Mo(C(O)Me)(S2COR)(CO)(PMe3)2 undergoes loss of a sulfur atom from the coordinated xanthate and coupling with the acyl ligand to form complexes containing coordinated alkoxythiocarbonyl and monothioacetate ligands. The latter can be metathetically replaced by KS2COR. (iii) Upon heating at 70°C η2-acyl-dicarbonyl bispirazolilborate complexes of molybdenum of the type Mo(H2B(pz*)2)(η2-C(O)Me)(CO)2(PMe3) (pz* = 3,5-dimethyl-pyrazol-1-yl) yield functionalized acyl ligands derived from the stereo- and regioselective intramolecular addition of one of the B---H bonds of the H2B(pz*)2 group across the C=O moiety of the η2-acyl group. (iv) The η2-acyl-isocyanide complexes {Mo}(η2-C(O)R)(CNR′) ({Mo} = Mo(H2B(pz*)2)(CO)(PMe3)) undergo irreversible thermal isomerization to the corresponding η2-iminoacyl-carbonyl derivatives {MO}(η2-C(NR′)R)(CO). This isomerization reaction follows first-order kinetics. 相似文献
5.
《Journal of molecular catalysis. A, Chemical》2002,190(1-2):131-143
The reaction of norbornene (NBE) and norbornadiene (NBD) in the presence of seven-coordinate tungsten(II) and molybdenum(II) complexes of the [(CO)4M(μ-Cl)3M(SnCl3)(CO)3] and [MCl(M′Cl3)(CO)3(NCMe)2] (M=W, Mo; M′=Sn, Ge) types leads to ring-opening metathesis polymerization (ROMP) and to the formation of high molecular weight polymers. The geometric structure of these polymers was determined by means of 1H- and 13C-NMR spectroscopy. The monitoring of the reaction between cyclic olefins and the metal complex by means of 1H-NMR spectroscopy allowed us to observe the coordination of NBD to metal atoms in the initiation step of the polymerization process. Compounds of the [MCl(SnCl3)(CO)3(η4-NBD)] type prepared directly from [(CO)4M(μ-Cl)3M(SnCl3)(CO)3] or [MCl(M′Cl3)(CO)3(NCMe)2] (M=W, Mo) in the presence of an excess of NBD initiate the ROMP reaction immediately. The detection of the first-formed products in the reaction between the metal complex and cyclic olefins provides valuable information concerning the nature of the initiating species. 相似文献
6.
Zheng-Zhi Zhang Ao Yu Hua-Ping Xi
Ru-Ji Wang
Hong-Gen Wang 《Journal of organometallic chemistry》1994,470(1-2):223-229The strong π-acid ligand Ph2PN(iBu)PPh2 reacts with Co2(CO)S (1:1) to give Co2[μ-Ph2PN(iBu)PPh2] (μ-CO)2(CO)4 (1); however, when the ratio is 2:1 a novel species [Co{Ph2PN(iBu)PPh2-P,P′}2(CO)][Co(CO)4] (2) has been obtained. Crystal data for 2: Mr = 1140.83; triclinic, space group P
, a = 12.330(2), b = 13.340(2), c = 18.122(3) Å, = 86.63(1), β = 80.75(1), γ = 84.24(1)°, V = 2924 Å3, Z = 2; R = 0.060 for 3711 reflections having I 3σ(I). The results of X-ray diffraction, ESR, variable-temperature magnetic susceptibility, conductivity, and XPS analysis support that the species 2 is a d9-d9 cage molecule-pair. The mechanism for the formation of the species 2 has been investigated initially by 31P NMR. 相似文献
7.
Victorio Cadierno Marí a Pilar Gamasa Jos Gimeno Elena Lastra 《Journal of organometallic chemistry》1996,510(1-2):207-211
The novel alkynyldithiocarboxylate complexes [Fe(η5-C5H5)(S2CCCR) (dppm-P)] (3a,b) and [Fe(η5-C5H5)(S2CCCR)(PPh3)] (4a,b) were obtained through the insertion of CS2 into the iron-akynyl bond in the complexes [Fe(η5-C5H5)(CCR)(L)(L′] L, L′ = dppm R = Ph (1a), tBu(1b); L = (CO), L′ = (PPh3) R = Ph (2a), tBu (2b). Variable-temperature 31P{1H} NMR studies indicate the presence of two different isomers, [Fe(η5-C5H5)(η3-S,C,S′---S2CCCR)(L)(L′)] and [Fe(η5-C5H5(η2-S,S′-S2CCCR)(L)(L′)], which rapidly interconvert at room temperature. The synthesis of the precursor complex [Fe(η5-C5H5)(CCtBu)(CO)(PPh3)] is also described. 相似文献
8.
J. Forni s E. Lalinde A. Martí n M. T. Moreno 《Journal of organometallic chemistry》1995,490(1-2):179-188
The study of the reactivity of [Pt2M4(CCR)8] (M=Ag or cu; R=Ph or tBu) towards different neutral and anionic ligands is reported. This study reveals that reactions of the phenylacetylide derivatives [Pt2M4(CCPh)8] with anionic, X− (X=Cl or Br) or neutral donors (CNtBu or py) in a molar ratio 1:4 (m/donor ratio 1:1) yield the trinuclear anionic (NBu4)2[{Pt(CCPh)4 (MX)2] (M=Ag or Cu, X =Cl or Br) or neutral [{Pt(CCPh04=sAGL)2] (L=CNtBu or py) complexes, respectively. The crystal structure of (NBu4)2[{Pt(CCPh)4}(CuBr)2](4) shows that the anion is formed by a dianionic Pt(CCPh)4 fragment and two neutral CuBr units joined through bridging alkynyl ligands. All the alkynyl groups are σ bonded to Pt and η2-coordinated to a Cu atom which have an approximately trigonal-planar geometry. By contrast, similar reactions with [Pt2M4(CCtBu)8] (molar ratio M/donor 1:1) afford hexanuclear dianionic (NBu4)2[Pt2M4(CCtBu)8X2] or neutral [Pt2Ag4(CCtBu08Py2]. Only by treatment with a large exces of Br − (molar ratio M/Br− 1:2) are the trinuclear complexes (NBu4)2[{Pt(CCtBu4 (MBr)2] (M=Ag, Cu) obtained. Attempted preparations of analogous complexes with phosphines (L′=PPh3 or PEt3) by reactions of [Pt2M4(CCR8] with L′ leads to displacement of alkynyl ligands from platinum and formation of neutral mononuclear complexes [trans-Pt(CCR)2L′2]. 相似文献
9.
A series of pentacarbonyl complexes of chromium and molybdenum with unicoordinated-diphosphines, M(CO)5(η1-P-P) (P-P = dppe, dppp, dppb) has been prepared by amine oxide-induced phosphine substitution of the binary carbonyls. The basicity of the pendant phosphine groups was demonstrated by their ready conversion to the diphosphine-bridged heterobimetallic complexes (OC)5M(μ-P-P)M′(CO)5 (M, M′= Cr, Mo, W; M ≠ M′) in the presence of MCO)5(CH3CN). The complexes were characterized by IR and NMR (1H and 31P-{1H}) spectroscopy. 相似文献
10.
The reactions of BrMn(CO)5 with the non-chelating stereochemically rigid bidentate ligands (L-L) 1,3-, and 1,4-diisocyanobenzene, 4,4′-diisocyanobiphenyl, and 4,4′-diisocyanodiphenylmethane afford well characterized complexes of the types BrMn(CO)4(L-L), BrMn(CO)3(L-L)2, and [BrMn(CO)4]2(L-L). Similar reactions with [RC5H4Mn(CO)2NO]+PF6− gave mixtures of oligomers of the type [(RC5H4MnNO)n(L-L)n+1]n+[PF6−]n. 相似文献
11.
The reactions of M(CO)4(R′-DAB) (M = Mo) or W; R′-DAB = R′-N=CHCH=NR′ (R′ = i-propyl, t-butyl, or cyclohexyl) with SnCl4 in dichloromethane solution result in the formation, in high yield, of the orange, diamagnetic, seven-coordinate oxidative-addition products M(CO)3(R′-DAB)(SnCl3)Cl. The reactions of Mo(CO)3(R′-DAB)(SnCl3)Cl (R′ = i-Pr or Cy) with an excess of alkyl isocyanide RNC (R = CHMe2, CMe3, or C6H11) in the presence of KPF6 lead to the formation of [Mo(CNR)4(R′-DAB)Cl]PF6 or [Mo(CNR)5(R′-DAB)](PF6)2 depending upon the reaction stoichiometry and reaction conditions. The monocationic chloro species are converted to [Mo(CNR)5(R′-DAB)](PF6)2 upon reflux with the stoichiometric amount of RNC. Under similar reactions conditions M(CO)3(t-Bu-DAB)(SnCl3)Cl (M = Mo or W) derivatives react with alkyl isocyanides with the reductive-elimination of the elements of SnCl4 and the formation of octahedral M(CO)3(CNR)(t-Bu-DAB). The dark red compounds [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) react readily with cyanide ions at ambient temperatures in methanol to yield [Mo(CNCMe3)4(R′-DAB)(CN)]PF6. Attempts to thermally dealkylate the parent complexes [Mo(CNCMe3)5(R′-DAB)](PF6)2 (R′ = i-Pr or Cy) to these same cyano species were unsuccessful. 相似文献
12.
Kom-Bei Shiu Li-Yuan Yeh
Shie-Ming Peng
Ming-Chu Cheng 《Journal of organometallic chemistry》1993,460(2):203-211The neutral nitrogen-bidentate ligand, diphenylbis(3,5-dimethylpyrazol-1-yl)methane, Ph2CPz′2, can readily be obtained by the reaction of Ph2CCl2 with excess HPz′ in a mixed-solvent system of toluene and triethylamine. It reacts with [Mo(CO)6] in 1,2-dimethoxyethane to give the η2-arene complex, [Mo(Ph2CPz′2)(CO)3] (1). This η2-ligation appears to stabilize the coordination of Ph2CPz′ 2 in forming [Mo(Ph2CPz′2)(CO)2(N2C6H4NO2-p)][BPh4] (2) and [Mo(Ph2CPz′2)(CO)2(N2Ph)] [BF4] (3) from the reaction of 1 with the appropriate diazonium salt but the stabilization seems not strong enough when [Mo{P(OMe)3} 3(CO)3] is formed from the reaction of 1 with P(OMe)3. The solid-state structures of 1 and 3 have been determined by X-ray crystallography: 1-CH2Cl2, monoclinic, P21/n, a = 11.814(3), b = 11.7929(12), c = 19.46 0(6) Å, β = 95.605(24)°, V = 2698.2(11) Å3, Z = 4, Dcalc = 1.530 g/cm3 , R = 0.044, Rw = 0.036 based on 3218 reflections with I > 2σ(I); 2 (3)-1/2 hexane-1/2 CH3OH-1/2 H2O-1 CH2Cl2, monoclinic, C2/c, a = 41.766(10), b = 20.518(4), c = 16.784(3) Å, β = 101.871(18)°, V = 14076(5) Å3, Z = 8, Dcalc = 1.457 g/cm3, R = 0.064, Rw = 0.059 based on 5865 reflections with I > 2σ(I). Two independent cations were found in the asymmetric unit of the crystals of 3. The average distance between the Mo and the two η2-ligated carbon atoms is 2.574 Å in 1 and 2.581 and 2.608 Å in 3. The unfavourable disposition of the η2-phenyl group with respect to the metal centre in 3 and the rigidity of the η2-arene ligation excludes the possibility of any appreciable agostic C---H → Mo interaction. 相似文献
13.
The potential of Fe(CO)4(η1-dppf) (dppf = 1,1′-bis(diphenylphosphino)ferrocene) as a precursor for heterometallic species is fully expanded in the synthesis of (OC)4Fe(μ-dppf)Cr(CO)5, (OC)4Fe(μ-dppf)W(CO)5, and (OC)4Fe(μ-dppf)Mn2(CO)9, all of which have been characterized by IR, NMR (1H and 31P) and elemental analyses. The low energy requirement of TMNO (Me3NO · 2H2O)decarbonylation allows the formation of monosubstituted Mn2(CO)10 as the major product. This aspect is further substantiated by the isolation of Mn4(CO)18(μ-dppf) in which the single bridging of a diphosphine group between two Mn2(CO)9 moieties is unprecedented. 相似文献
14.
Behaviour of water-soluble dinuclear rhodium complexes in the hydroformylation reaction of oct-1-ene
The biphasic hydroformylation reaction of oct-1-ene, has been investigated by using the water-soluble dinuclear complex [Rh2(μ-StBu)2(CO)2(TPPTS)2] as precursor. Addition of ethanol as a cosolvent dramatically improved the yields but the good regioselectivity in linear aldehyde observed for neat oct-1-ene—water systems (97%) decreased to 83% (for 22% ethanol w/w). It is shown that the dinuclear framework cannot be maintained, that the mononuclear complex [RhH(CO)(TPPTS)3] is formed, and that thiol and significant amounts of [Rh2(μ-StBu)2(CO)4] move into the organic phase. This reaction from the dinuclear species requires the simultaneous presence of water and carbon monoxide. Introduction of the water-soluble thiol HS(CH2)3NMe2 in the bridging positions affords the complex [Rh2(μ-S(CH 2)3NHMe2)2(CO)2(TPPTS)2]Cl2 which can be kept in the aqueous hase but has a low level of catalytic activity. 相似文献
15.
The compounds [MI2(CO)3(NCMe)2] (M = Mo or W) react with one equivalent of thiourea (tu) in MeOH or N,N,N′,N′-tetramethylthiourea (tmtu) in CH2Cl2 at room temperature to initially afford the monoacetonitrile compounds [MI2(CO)3(NCMe)L] (L = tu or tmtu) which rapidly transform to the isolated iodide bridged dimers, [M(μ-I)I(CO)3L]2 with loss of acetonitrile. Reaction of [WI2(CO)3(NCMe)2] with two equivalents of tu or tmtu gave the expected mononuclear seven-coordinate compounds [WI2(CO)3L2]. However, reaction of [MoI2(CO)3(NCMe)2] with two equivalents of tu or tmtu rapidly affords the iodide-bridged dimers [Mo(μ-I)I(CO)2L2]2 with loss of carbon monoxide from [MoI2(CO)3L2]. The low temperature (−70°C) 13C NMR spectrum of [Mo(μ-I)I(CO)2 {SC(NMe2)2}2]2 suggests the complex is based on two capped octahedra with a carbonyl ligand capping each octahedral face. 相似文献
16.
Recent results (post-1990) on the synthesis and structures of bis(trimethylsilyl)methyls M(CHR2)m (R = SiMe3) of metals and metalloids M are described, including those of the crystalline lipophilic [Na(μ-CHR2)]∞, [Rb(μ-CHR2)(PMDETA)]2, K4(CHR2)4(PMDETA)2, [Mg(CHR2)(μ-CHR2)]∞, P(CHR2)2 (gaseous) and P2(CHR2)4, [Yb(CHR2)2(OEt2)2] and [{Yb(CR3)(μ-OEt)(OEt2)}2]; earlier information on other M(CHR2)m complexes and some of their adducts is tabulated. Treatment of M(CHR2) (M = Li or K) with four different nitriles gave the X-ray-characterized azaallyls or β-diketinimates
,
and
(LL′ = N(R)C(tBu)CHR, L′L′ = N(R)C(Ph)C(H)C(Ph)NR, LL″ = N(R)C(Ph)NC(H)C(Ph)CHR, R = SiMe3 and Ar = C6H3Me2-2,5). The two lithium reagents were convenient sources of other metal azaallyls or β-diketinimates, including those of K, Co(II), Zr(IV), Sn(IV), Yb(II), Hf(IV) and U(VI)/U(III). Complexes having one or more of the bulky ligands [LL′]−, [L′L′]−, [LL]−, [LL″]−, [L″L]−, [LL]− and [{N(R)C(tBu)CH}2C6H4-2]2− are described and characterized (LL = N(H)C(Ph)C(H)C(Ph)NH, L″L = N(R)C(tBu)C(H)C(Ph)NR, LL = N(R)C(tBu)CHPh). Among the features of interest are (i) the contrasting tetrahedral or square-planar geometry for
and
, respectively, and (ii) olefin-polymerization catalytic activity of some of the zirconium(IV) chlorides. 相似文献
17.
Kouki Matsubara Shoji Mima Takashi Oda Hideo Nagashima 《Journal of organometallic chemistry》2002,650(1-2):96-107
Novel isonitrile derivatives of a diruthenium carbonyl complex, (μ2,η3:η5-guaiazulene)Ru2(CO)5 (2), were synthesized by substitution of a CO ligand by an isonitrile, and were subjected to studies on thermal and photochemical haptotropic interconversion. Treatment of 2 (a 45:55 mixture of two haptotropic isomers, 2-A and 2-B) with RNC at room temperature resulted in coordination of RNC and alternation of the coordination mode of the guaiazulene ligand to form (μ2,η1:η5-guaiazulene)Ru2(CO)5(CNR), 5d–5f, [5d; R=tBu, 5e; 2,4,6-Me3C6H2, or 5f; 2,6-iPr2C6H3] in moderate to good yields. Thermal dissociation of a CO ligand from 5 at 60 °C resulted in quantitative formation of a desirable isonitrile analogue of 2, (μ2,η3:η5-guaiazulene)Ru2(CO)4(CNR), 4d–4f, [4d; R=tBu, 4e; 2,4,6-Me3C6H2, or 4f; 2,6-iPr2C6H3], as a 1:1 mixture of the two haptotropic isomers. A direct synthetic route from 2 to 4d–4f was alternatively discovered; treatment of 2 with one equivalent of RNC at 60 °C gave 4d–4f in moderate yields. All of the new compounds were characterized by spectroscopy, and structures of 5d (R=tBu) and 4d-A (R=tBu) were determined by crystallography. Thermal and photochemical interconversion between the two haptotropic isomers of 4d–4f revealed that the isomer ratios in the thermal equilibrium and in the photostatic state were in the range of 48:52–54:46. 相似文献
18.
Optimised hydrothermal synthesis of multi-dimensional hybrid coordination polymers containing flexible organic ligands 总被引:2,自引:0,他引:2
Filipe A. Almeida Paz Joo Rocha Jacek Klinowski Tito Trindade Fa-Nian Shi Luís Mafra 《Progress in Solid State Chemistry》2005,33(2-4):113-125
In this paper, we summarise our recent research interest in the hydrothermal synthesis and structural characterisation of multi-dimensional coordination polymers. The use of N-(phosphonomethyl)iminodiacetic acid (also referred to as H4pmida) in the literature as a versatile chelating organic ligand is briefly reviewed. This molecule plays an important role in the formation of centrosymmetric dimeric [V2O2(pmida)2]4− anionic units, which were first used by us as building blocks to construct novel coordination polymers. Starting with [V2O2(pmida)2]4− in solution, we have isolated [M2V2O2(pmida)2(H2O)10] species (where M2+ = Mn2+, Co2+ or Cd2+) via the hydrothermal synthetic approach, which were then employed for the construction of [CdVO(pmida)(4,4′-bpy)(H2O)2]·(4,4′-bpy)0.5·(H2O), [CoVO(pmida)(4,4′-bpy)(H2O)2]·(4,4′-bpy)0.5, [Co(H2O)6][CoV2O2(pmida)2(pyr)(H2O)2]·2(H2O) and [Cd2V2O2(pmida)2(pyr)2(H2O)4]·4(H2O) by the inclusion of bridging organic ligands in the reactive mixtures, such as pyrazine (pyr) and 4,4′-bipyridine (4,4′-bpy). These materials can contain channel systems, and exhibit magnetic behaviour, not only due to the V4+ centres but also to the transition metal centres which establish the links between neighbouring dimeric [V2O2(pmida)2]4− anionic units. A closely related anionic moiety, [Ge2(pmida)2(OH)2]2−, was engineered to allow the study of such crystalline hybrid materials using one- and two-dimensional high-resolution solid-state NMR. 相似文献
19.
Malcolm H. Chisholm John C. Huffman Ivan P. Parkin William E. Streib 《Polyhedron》1990,9(24):2941-2952
Toluene solutions of M2(NMe2)6 (M = Mo, W) react with mesitylene selenol (Ar′SeH) to give M2(SeAr′) 6 complexes. MO2(OR)6 (R = tBu, CH2tBu) react with excess> 6 fold) Ar′SeH to give Mo2 (SeAr′)6, whilst W2(OR)6(py)2 (R = iPr, CH2tBu) react with excess (> 6 fold) Ar′SeH to give W2(OR)2(SeAr′)4. Reaction of MO2(OPri)6 with Ar′SeH produces Mo2(OPri)2 (SeAr′)4 which crystallizes in two different space groups. These areneselenato complexes are air-stable and insoluble in common organic solvents. X-ray crystallographic studies revealed that the Mo2(SeAr′)6 and W2(SeAr′)6 compounds are isostructural in the solid state and adopt ethane-like staggered configurations with the following important structural parameters, M---M (W---W/Mo---Mo) 2.3000(11)/2.2175(13) Å, M---Se 2.430 (av.)/2.440 (av.) Å, M---M---SE 97.0° (av.)°. In the solid state W2(OiPr)2(SeAr′)4 adopts the anti-configuration with crystallographically imposed Ci symmetry and W---W 2.3077(7) Å, W---Se 2.435 (av.) Å, W---O 1.858(6) Å; W---W---SE 100.27(3)°, 93.8(3)° and W---W---O 108.41(17)°. Mo2(OPri)2(SeAr′) 4 crystallizes in both P
and A2/a space groups in which the molecules are isostructural with each other and the tungsten analogue. Important bond lengths and angles are Mo---Mo 2.180(24) Å, Mo---Se 2.432(av.) Å, Mo---O 1.872(9) Å, Mo---Mo---Se 99.39(9)°, 94.71(8)°, Mo---Mo---O 107.55(28)°. 相似文献
20.
Two mononuclear RuII complexes of polypyridyl ligands, cis-[Ru(bpy)2(4,4′-bpy)Cl](PF6)·H2O (1) and cis-[Ru(phen)2(CH3CN)2](PF6)2 (2) (bpy=2,2′-bipyridyl, 4,4′-bpy=4,4′-bipyridyl, and PHEN=1,10-phenanthroline), have been synthesized and characterized by elemental analyses, IR and UV–vis spectra. The crystal structures of both complexes have been determined by X-ray diffraction, indicating that each RuII center is hexa-coordinated (RuN5Cl for 1 and RuN6 for 2) and takes a distorted octahedral geometry. The favored feature of both complexes is that they are quite useful complex precursors for further constructing new functional architectures. 相似文献