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1.
Reaction of optically active ketone complexes (+)-( R)-[(η 5-C 5H 5)Re(NO)-(PPh 3)(η 1-O=C(R)(CH 3)] + BF 4− (R = CH 2CH 3, CH(CH 3) 2m C(CH 3) 3, C 6H 5) with K(s-C 4H 9) 3BH gives alkoxide complexes (+)-( RS)-(η 5-C 5H 5)Re(NO)(PPh 3)-(OCH(R)CH 3) (73–90%) in 80–98% de. The alkoxide ligand is then converted to Mosher esters (93–99%) of 79–98% de. 相似文献
2.
The interaction of [(η 5-C 5H 4Bu t) 2YbCl · LiCl] with one equivalent of Li[(CH 2) (CH 2)PPh 2] in tetrahydrofuran gave [Ph 2PMe 2][(η 5-C 5H 4Bu t) 2Li] (1) and [(η 5-C 5H 4Bu t) 2Yb(Cl)CH 2P(Me)Ph 2] (2) in 10% and 30% yields, respectively. 1 could also be prepared in 70% yield from the reaction of [Ph 2PMe 2][CF 3SO 3] with two equivalents of (C 5H 4Bu t)Li. Both compounds have been fully characterized by analytical, spectroscopic and X-ray diffraction methods. The solid state structure of 1 reveals a sandwich structure for the [(η 5-C 5H 4Bu t) 2Li] − anion. 相似文献
3.
A novel tetranuclear terbium(III) complex [Tb 4(OH) 4(pybet) 6(H 2O) 8][Tb 4(OH) 4(pybet) 6(H 2O) 7 (NO 3)](ClO 4) 14·6H 2O has been synthesized and shown by X-ray crystallography to have a cubane-like Tb 4(μ 3-OH) 4(μ 2-carboxylato-O,O′) 6 core. The ligand pybet is pyridinoacetate, C 5H 5+N-CH 2CO 2−. Magnetic susceptibility data were measured for this Tb 4 complex in the range of 2.0–320 K and in fields of 1.0 G to 50.0 kG. It is concluded that either there is very weak antiferromagnetic exchange interaction ( J = −0.015 cm −1) or there is a small crystal-field splitting of the 7F 6 Tb III ground state. 相似文献
4.
The generality of a two-electron reduction process involving an
mechanism has been established for M 3(CO) 12 and M 3(CO) 12− n(PPh 3) n (M = Ru, Os) clusters in all solvents. Detailed coulometric and spectral studies in CH 2Cl 2 provide strong evidence for the formation of an ‘opened’ M 3(CO) 122− species the triangulo radical anions M 3(CO) 12−· having a half-life of < 10 −6 s in CH 2Cl 2. However, the electrochemical response is sensitive to the presence of water and is concentration dependent. An electrochemical response for “opened” M 3(CO) 122− is only detected at low concentrations < 5 × 10 −4 mol dm −3 and under drybox conditions. The electroactive species ground at higher concentrations and in the presence of water M 3(CO) 112− and M 6(CO) 182− were confirmed by a study of the electrochemistry of these anions in CH 2Cl 2; HM 3(CO) 11− is not a product. The couple [M 6(CO) 18] −/2− is chemically reversible under certain conditions but oxidation of HM 3(CO) 11− is chemically irreversible. Different electrochemical behaviour for Ru 3(CO) 12 is found when [PPN][X] (X = OAc −, Cl −) salts are supporting electrolytes. In these solutions formation of the ultimate electroactive species [μ-C(O)XRu 3(CO) 10] − at the electrode is stopped under CO or at low temperatures but Ru 3(CO) 12−· is still trapped by reversible attack by X presumably as [η 1-C(O)XRu 3(CO) 11] −. It is shown that electrode-initiated electron catalysed substitution of M 3(CO) 12 only takes place on the electrochemical timescale when M = Ru, but it is slow, inefficient and non-selective, whereas BPK-initiated nucleophilic substitution of Ru 3(CO) 12 is only specific and fast in ether solvents particulary THF. Metal---metal bond cleavage is the most important influence on the rate and specificity of catalytic substitution by electron or [PPN]-initiation. The redox chemistry of M 3(CO) 12 clusters (M = Fe, Ru, Os) is a consequence of the relative rates of metal---metal bond dissociation, metal-metal bond strength and ligand dissociation and in many aspects resembles their photochemistry. 相似文献
5.
The new iodoammonium salts o-C 6H 4(NH 2) 2I +I − (1) and o-C 6H 4(NH 2) 2I + AsF 6− (2) were prepared by reaction of o-phenylene diamine with I 2 or I 3+AsF 6−, respectively. Compound 1 reacts with AlI 3 yielding quantitatively the corresponding tetraiodoaluminate o-C 6H 4(NH 2) 2I +AlI 4− (3). The species were characterized by chemical analysis, vibrational (IR and Raman) and temperature-dependent 1H NMR spectropscopy. Direct evidence for a N---I bond was found in the Raman spectra of 1, 2 and 3 (ν(NI) = 599–600 cm −1). 相似文献
6.
MoO 2(C 5H 7O 2) 2, where C 5H 7O 2 is 2,4-pentanedione (acac), reacts with 2-2′ pyridylbenzoxazole in acetone to give a product with stoichiometry, Mo 3C 24H 16N 6O 12. This product dissolves readily in dimethylformamide to give a brown solution which on standing for several weeks yielded crystals. An X-ray structure determination showed these crystals to contain uncoordinated 2-2′pyridylbenzoxazole and [(CH 3) 2NH 2] 4+[Mo 8O 26] 4−. 相似文献
7.
Reaction of ansa-cyclopentadienyl pyrrolyl ligand (C 5H 5)CH 2(2-C 4H 3NH) (2) with Ti(NMe 2) 4 affords bis(dimethylamido)titanium complex [(η 5-C 5H 4)CH 2(2-C 4H 3N)]Ti(NMe 2) 2 (3) via amine elimination. A cyclopentadiene ligand with two pendant pyrrolyl arms, a mixture of 1,3- and 1,4-{CH 2(2-C 4H 3NH)} 2C 5H 4 (4), undergoes an analogous reaction with Ti(NMe 2) 4 to give [1,3-{CH 2(2-C 4H 3N)} 2(η 5-C 5H 3)]Ti(NMe 2) (5). Molecular structures of 3 and 5 have been determined by single crystal X-ray diffraction studies. 相似文献
8.
Reaction of the optically active primary amine (S)-(—)--methylbenzylamine with trimethylaluminium in heptane affords the crystalline organoaluminium dimer (S)-(—)-(S)-(—)-[(C 6H 5)CH(CH 3)NHA1(CH 3) 2] 2. Isolated as large, colourless, extremely air-sensitive prismatic crystals, the title compound crystallizes in the orthorhombic space group P2 12 12 1 with unit cell parameters a = 8.406(3), b = 15.505(4), c = 17.547(5) Å, V = 2287 Å 3 and p = 1.03 g cm −3 for Z = 4. Least-squares refinement based on 1477 observed reflections converged at R = 0.056, R w = 0.058. Methane was eliminated during the course of the reaction due to cleavage of A1---C and N---H bonds resulting in an asymmetric A1 2N 2 fragment at the core of the organoaluminium dimer. The mean A1---C bond distance in the dimethylaluminium units is 1.930(8), while the mean A1---N bond distance is 1.950(5) Å. Specific rotation ([] D25 in CH 2C1 2)of the dimer is determined to be - 20.6°. 相似文献
9.
Thermal displacement of coordinated nitriles RCN (R = CH 3, C 2H 5 or n-C 3H 7) in [C 5H 5Fe(L 2)(NCR)]X complexes (L 2 = P(OCH 3) 3) 2, (P(OC 6H 5) 3) 2 or (C 6H 5) 2PC 2H 4P(C 6H 5) 2 (DPPE)) by E(CH 3) 2 affords high yields of [C 5H 5Fe(L 2)(E(CH 3) 2)]X compounds (E = S, Se and Te; X = BF 4 or PF 6). Spectroscopic data and ligand displacement reactions are presented and discussed together with related observations on [C 5H 5Fe(CO) 2(E(CH 3) 2)]BF 4 compounds. The molecular structure of [C 5H 5Fe(P(OCH 3) 3) 2(S(CH 3) 2)]PF 6 was determined by a single-crystal X-ray diffraction study: monoclinic, space group P2 1/ n- C52h (No. 14) with a = 8.4064(12), b = 11.183(2), c = 50.726(8) Å, β = 90.672(13)° and Z = 8 molecules per unit cell. The coordination sphere of the iron atom is pseudo-tetrahedral with an Fe---S bond distance of 2.238 Å. 相似文献
10.
Reduction of (C 5H 5) 2TiCl 2 with Zn in presence of benzyl cyanide gives the (μ-alkyl-ideneamido)titanocene complex [(C 5H 5) 2TiCl] 2[μ-{N=C(CH 2C 6H 5)---C(CH 2C 6H 5)=N}] with C---C bond formation between two benzyl cyanide molecules. X-ray structure investigation indicates a symmetrical structure. The C=N distances are smaller than usual, the Ti---N distances are very short, and the Ti---N---C angle differs only a little from 180°, which infers a heteroallene structure of the complex. 相似文献
11.
Rate constants for the tunneling reaction (HD + D → h + D 2) in solid HD increase steeply with increasing temperature above 5 K, while they are almost constant below 4.2 K. The apparent activation energy for the tunneling reaction above 5 K is 95 K, which is consistent with the energy (91–112 K) for vacancy formation in solid hydrogen. The results above 5 K were explained by the model that the tunneling reaction was accelerated by a local motion of hydrogen molecules and hydrogen atoms. The model of the tunneling reaction assisted by the local motion of the reactans and products was applied to the temperature dependence of the proton-transfer tunneling reaction (C 6H 6− + C 2H 5OH → C 6H 7 + C 2H 5O −) in solid ethanol, the tunneling elimination of H 2 molecule of H 2 molecule ((CH 3) 2 CHCH(CH 3) 2+ → (CH 3) 2 C = C(CH 3) 2+ + H 2) in solid 2,3-dimethylbutane, and the selective tunneling reaction of H atoms in solid neo-C 5H 12-alkane mixtures. 相似文献
12.
The dimethylphosphino substituted cyclopentadienyl precursor compounds [M(C 5Me 4CH 2PMe 2)], where M=Li + (1), Na + (2), or K + (3), and [Li(C 5H 4CR′ 2PMe 2)], where R′ 2=Me 2 (4), or (CH 2) 5 (5), [HC 5Me 4CH 2PMe 2H]X, where X −=Cl − (6) or PF 6− (7) and [HC 5Me 4CH 2PMe 2] (8), are described. They have been used to prepare new metallocene compounds, of which representative examples are [Fe(η-C 5R 4CR′ 2PMe 2) 2], where R=Me, R′=H (9); R=H and R′ 2=Me 2 (10), or (CH 2) 5 (11), [Fe(η-C 5H 4CMe 2PMe 3) 2]I 2 (12), [Fe{η-C 5Me 4CH 2P(O)Me 2} 2] (13), [Zr(η-C 5R 4CR′ 2PMe 2) 2Cl 2], where R=H, R′=Me (14), or R=Me, R′=H (15), [Hf(η-C 5H 4CMe 2PMe 2) 2]Cl 2] (16), [Zr(η-C 5H 4CMe 2PMe 2) 2Me 2] (17), {[Zr(η-C 5Me 4CH 2PMe 2) 2]Cl}{(C 6F 5) 3BClB(C 6F 5) 3} (18), [Zr{(η-C 5Me 4CH 2PMe 2) 2Cl 2}PtI 2] (19), [Mn(η-C 5Me 4CH 2PMe 2) 2] (20), [Mn{(η-C 5Me 4CH 2PMe 2B(C 6F 5) 3} 2] (21), [Pb(η-C 5H 4CMe 2PMe 2) 2] (23), [Sn(η-C 5H 4CMe 2PMe 2) 2] (24), [Pb{η-C 5H 4CMe 2PMe 2B(C 6F 5) 3} 2] (25), [Pb(η-C 5H 4CMe 2PMe 2) 2PtI 2] (26), [Rh(η-C 5Me 4CH 2PMe 2)(C 2H 4)] 29, [M(η,κ P-C 5Me 4CH 2PMe 2)I 2], where M=Rh (30), or Ir, (31). 相似文献
13.
The reactions of the half-sandwich molybdenum(III) complexes CpMo(η 4-C 4H 4R 2)(CH 3) 2, where Cp=η 5-C 5H 5 and R=H or CH 3, with equimolar amounts of B(C 6F 5) 3 have been investigated in toluene. EPR monitoring shows the formation of an addition product which does not readily react with Lewis bases such as ethylene, pyridine, or PMe 3. The analysis of the EPR properties and the X-ray structure of a decomposition product obtained from dichloromethane, [CpMo(η 4-C 4H 6)(μ-Cl)(μ-CH 2)(O)MoCp][CH 3B(C 6F 5) 3], indicate that the borane attack has occurred at the methyl position. 相似文献
14.
The ruthenium(II) complex Ru(CO) 2(NH 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I has been prepared by the reaction of Ru(CO) 4(Si(C 6H 5)(CH 3) 2)I with benzylamine. Two-dimensional homonuclear 1H NMR experiments examine the scalar coupling of the enantiotopic amino and methylene protons of the benzylamine ligand. X-ray analysis of Ru(CO) 2(NH 2CH 2C 6H 5) 2(Si(C 6H 5)(CH 3) 2)I·1/3C 5H 12 (triclinic; P
; a = 14.266(4), b = 15.748(5), c = 20.082(6) Å; = 94.38(3), β = 96.30(2), γ = 101.52(2)°) indicates three crystallographically unique complexes form a clathrate with a pentane guest. 相似文献
15.
The crystal structures of propionaldehyde complex ( RS, SR)-(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 3)] + PF 6− (1b + PF 6s−; monoclinic, P2 1/ c (No. 14), a = 10.166 (1) Å, b = 18.316(1) Å, c = 14.872(2) Å, β = 100.51(1)°, Z = 4) and butyraldehyde complex ( RS, SR)-[(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHCH 2CH 2CH 3)] + PF 6− (1c +PF 6−; monoclinic, P2 1/ a (No. 14), a = 14.851(1) Å, b = 18.623(3) Å, c = 10.026(2) Å, β = 102.95(1)°, Z = 4) have been determined at 22°C and −125°C, respectively. These exhibit C
O bond lengths (1.35(1), 1.338(5) Å) that are intermediate between those of propionaldehyde (1.209(4) Å) and 1-propanol (1.41 Å). Other geometric features are analyzed. Reaction of [(η 5-C 5H 5)Re(NO)(PPh 3)(ClCH 2Cl)] + BF 4− and pivalaldehyde gives [(η 5-C 5H 5)Re(NO)(PPh 3)(η 2-O=CHC(CH 3) 3)] +BF 4− (81%), the spectroscopic properties of which establish a π C
O binding mode. 相似文献
16.
The electron donating water soluble phosphines, P{(CH 2) nC 6H 4- p-SO 3Na} 3, n = 1, 2, 3 and 6, react rapidly with Co 2(CO) 8 under two phase reaction conditions to yield the disproportionation products, [Co(CO) 3(P{(CH 2) nC 6H 4- p-SO 3Na 3} 2] [Co(CO) 4]. Selective precipitation yields the formally zwitterionic complex anions as the sodium salt, [Co(CO) 3(P{(CH 2) nC 6H 4- p-SO 3} 3) 2] 5−. The anions can be used as precursors to water soluble cobalt hydroformylation catalysts under two phase and supported aqueous phase conditions. The tendency to form alcohol products is low with these complexes. The behavior of the catalysts is consistent with an active species that remains water soluble during the reaction and is not leached into the nonaqueous phase. 相似文献
17.
The reaction of the anionic mononuclear rhodium complex [Rh(C 6F 5) 3Cl(Hpz)] t- (Hpz = pyrazole, C 3H 4N 2) with methoxo or acetylacetonate complexes of Rh or Ir led to the heterodinuclear anionic compounds [(C 6F 5) 3Rh(μ-Cl)(μ-pz)M(L 2)] [M = Rh, L 2 = cyclo-octa-1,5-diene, COD (1), tetrafluorobenzobarrelene, TFB (2) or (CO) 2 (4); M = Ir, L 2 = COD (3)]. The complex [Rh(C 6F 5) 3(Hbim)] − (5) has been prepared by treating [Rh(C 6F 5) 3(acac)] − with H 2bim (acac = acetylacetonate; H 2bim = 2,2′-biimidazole). Complex 5 also reacts with Rh or Ir methoxo, or with Pd acetylacetonate, complexes affording the heterodinuclear complexes [(C 6F 5) 3Rh(μ-bim)M(L 2)] − [M = Rh, L 2 = COD (6) or TFB (7); M = Ir, L 2 = COD (8); M = Pd, L 2 = η 3-C 3H 5 (9)]. With [Rh(acac)(CO) 2], complex 5 yields the tetranuclear complex [{(C 6F 5) 3Rh(μ-bim)Rh(CO) 2} 2] 2−. Homodinuclear Rh III derivatives [{Rh(C 6F 5) 3} 2(μ-L) 2] ·- [L 2 = OH, pz (11); OH, S tBu (12); OH, SPh (13); bim (14)] have been obtained by substitution of one or both hydroxo groups of the dianion [{Rh(C 6F 5) 3(μ-OH)} 2] 2− by the corresponding ligands. The reaction of [Rh(C 6F 5) 3(Et 2O) x] with [PdX 2(COD)] produces neutral heterodinuclear compounds [(C 6F 5) 3Rh(μ-X) 2Pd(COD)] [X = Cl (15); Br (16)]. The anionic complexes 1–14 have been isolated as the benzyltriphenylphosphonium (PBzPh 3+) salts. 相似文献
18.
LnCl 3 (Ln=Nd, Gd) reacts with C 5H 9C 5H 4Na (or K 2C 8H 8) in THF (C 5H 9C 5H 4 = cyclopentylcyclopentadienyl) in the ratio of 1 : to give (C 5H 9C 5H 4)LnCl 2(THF) n (orC 8H 8)LnCl 2(THF) n], which further reacts with K 2C 8H 8 (or C 5H 9C 5H 4Na) in THF to form the litle complexes. If Ln=Nd the complex (C 8H 8)Nd(C 5H 9C 5H 4)(THF) 2 (a) was obtained: when Ln=Gd the 1 : 1 complex [(C 8H 8)Gd(C %H 9)(THF)][(C 8H 8)Gd(C 5H 9H 4)(THF) 2] (b) was obtained in crystalline form. The crystal structure analysis shows that in (C8H8)Ln(C5H9C5H4)(THF)2 (Ln=Nd or Gd), the Cyclopentylcyclopentadieny (η5), cyclooctatetraenyl (η8) and two oxygen atoms from THF are coordinated to Nd3+ (or Gd3+) with coordination number 10. The centroid of the cyclopentadienyl ring (Cp′) in C5H9C5H4 group, cyclooctatetraenyl centroid (COTL) and two oxygens (THF) form a twisted tetrahedron around Nd3+ (or Gd3+). In (C8H8)Gd(C5H9C5H4)(THF), the cyclopentyl-cyclopentadienyl (η5), cyclooctatetraenyl (η8) and one oxygen atom are coordinated to Gd3+ with the coordination number of 9 and Cp′, COT and oxygen atom form a triangular plane around Gd3+, which is almost in the plane (dev. -0.0144 Å). 相似文献
19.
The compounds (π-C 5H 5)(CO) 2LM-X (L = CO, PR 3; M = Mo, W; X = BF 4, PF 6, AsF 6, SbF 6) react with H 2S, p-MeC 6H 4SH, Ph 2S and Ph 2SO(L′) to give ionic complexes [(π-C 5H 5)(CO) 2LML′] + X −. Also sulfur-bridged complexes, [(π-C 5H 5)(CO) 3W---SH---W(CO) 3(π-C 5H 5)] + AsF 6− and [(π-C 5H 5)(CO) 3M-μ-S 2C=NCH 2Ph-M(CO) 3(π-C 5H 5)], have been obtained. Reactions with SO 2 and CS 2 have been examined. 相似文献
20.
A series of heterodimetallic complexes of general formula (C 5R 5)M(μ-CO) 3RuC 5Me 5 (M = Cr, Mo, W; R = Me, Et) has been prepared in good yields by the reaction of [C 5R 5M(CO) 3] − with [C 5Me 5Ru(CH 3CN) 3] +. (C 5Me 4Et)W(μ-CO) 3Ru(C 5Me 5) was characterized by a crystal structure determination. The W---Ru bond length of 2.41 Å is consistent with the formulation of a metal-metal triple bond, while the unsymmetrical bonding mode of the three bridging carbonyl groups reflects the inherent non-equivalence of the two different C 5R 5M-units. Using [CpRu(CH 3CN) 3] + or [CpRu(CO) 2(CH 3CN)] + as the cationic precursor leads to the formation of dimetallic species (C 5R 5)M(CO) 5RuC 5H 5 with both bridging and terminal carbonyl groups. 相似文献
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