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1.
Rankin MA McDonald R Ferguson MJ Stradiotto M 《Angewandte Chemie (International ed. in English)》2005,44(23):3603-3606
2.
Bi-, tri-, and tetracyclic isoquinoline salts were readily synthesized in excellent yields at room temperature from readily available starting materials after three reaction steps. Aromatic C-H activation was first promoted by sodium acetate with [Cp*MCl2]2 (M = Rh, Ir) at room temperature to form cyclometalated compounds. Dimethylacetylenedicarboxylate was then found to insert into the metal-carbon bonds of the cyclometalated compounds. Finally, the insertion compounds underwent oxidative coupling to form the desired isoquinoline salts and regenerate [Cp*MCl2]2. All of the intermediate compounds following C-H activation, alkyne insertion, and oxidative coupling were fully characterized, including the determination of X-ray structures in several cases, and the results shed light on the overall mechanism. Moreover, it was possible to synthesize the isoquinoline salts from readily available starting materials using one-pot procedures; thus, this work provides a novel, efficient method for metal-mediated synthesis of heterocycles. 相似文献
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Treatment of [Cp*Rh(H(2)O)(3)](OTf)(2) (1) with Me(3)SiNH-t-Bu in acetone gave a hydroxyl-capped half-cubane [Cp*(3)Rh(3)(mu-OH)(3)(mu(3)-OH)](OTf)(3)(t-BuNH(3)) (2). Slow diffusion of Me(3)SiN(3) in diethyl ether into compound in acetone produced an azido-capped half-cubane [Cp*(3)Rh(3)(mu-N(3))(3)(mu(3)-N(3))](OTf)(2) (3). On the other hand, treating 1 with Me(3)SiN(3) in acetone gave an azido-bridged, dinuclear rhodium(III) complex [Cp*Rh(mu-N(3))(OH(2))](2)(OTf)(2) (4). Complexes 2 and 3 represent the first azido- or hydroxyl-capped, incomplete cubane-type Rh clusters. Under appropriate conditions, complexes 2 and 3 could be converted to complex 4. The structures of all products were determined by X-ray diffraction. 相似文献
4.
Minasian SG Krinsky JL Williams VA Arnold J 《Journal of the American Chemical Society》2008,130(31):10086-10087
A heterobimetallic complex with the first unsupported bond between an actinide and a group 13 element, (CpSiMe3)3U-AlCp* (Cp* = C5Me5) (1), was synthesized by reaction of (CpSiMe3)3U and 1/4(Cp*Al)4 in toluene. Density functional theory calculations indicate that the U-Al bond exhibits some covalent character resulting from a Cp*Al-->U charge-transfer. 相似文献
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The geometries, metal-ligand bond dissociation energies, and heats of formation of twenty sandwich and half-sandwich complexes of the main-group elements of Groups 1, 2, 13, and 14, and Zn have been calculated with quantum chemical methods. The geometries of the [E(Cp)] and [E(Cp)2] complexes were optimized using density functional theory at the BP86 level with valence basis sets, which have DZP and TZP quality. Improved energy values have been obtained by using coupled-cluster theory at the CCSD(T) level. The nature of the metal-ligand bonding has been analyzed with an energy-partitioning method. The results give quantitative information about the strength of the covalent and electrostatic interactions between En+ and (Cp-)n (n = 1, 2). The contributions of the orbitals with different symmetry to the covalent bonding are also given. 相似文献
6.
Azido Derivatives of the Pentamethylcyclopentadienyl Vanadium(IV)-Fragment. Molecular Structures of the Binuclear Complexes [Cp*VCl(N3)(μ-N3)]2 and [Cp*V(N3)2(μ-N3)]2 The stepwise reaction of Cp*VCl3 with excess trimethylsilyl azide (Me3Si–N3) in solution leads to the paramagnetic, azido-bridged complexes [Cp*VCl2(μ-N3)]2 ( 3 ), [Cp*VCl(N3)(μ-N3)]2 ( 4 ) and [Cp*V(N3)2(μ-N3)]2 ( 5 ) which were characterized by their IR and mass spectra. The azide-rich binuclear complex 5 is also formed if a pentane solution of Cp*V(CO)4 is stirred in the presence of excess Me3Si–N3 in an open vessel. According to the X-ray structure analyses both 4 and 5 are centrosymmetric molecules with a planar V(N)2V four-membered ring. In the absence of free trimethylsilyl azide, solutions of 3 – 5 lose dinitrogen slowly; in the presence of traces of air, 5 is thereby converted to the diamagnetic, oxo-bridged complex [Cp*V(O)(N3)]2(μ-O) ( 6 ). 相似文献
7.
Alvarez CS Boss SR Burley JC Humphry SM Layfield RA Kowenicki RA McPartlin M Rawson JM Wheatley AE Wood PT Wright DS 《Dalton transactions (Cambridge, England : 2003)》2004,(21):3481-3487
Manganocene, Cp(2)Mn, has been employed as a precursor in the synthesis of a range of Mn(II) dimers of the type [CpMn(micro-X)](2)[X = 8-NHC(9)H(6)N (1), N(Ph)(C(5)H(4)N)(2), N(4-EtC(6)H(4))(C(5)H(4)N)(3) and C[triple bond]CPh (4)] as well as the bis-adduct [Cp(2)Mn[HN=C(NMe(2))(2)](2)](5). The solid-state structures of 1-5 are reported. Variable-temperature magnetic measurements have been used to assess the extent of Mn(micro-X)Mn communication within the dimers of 1-4 as a function of the bridging ligands (X). 相似文献
8.
Tsang JY Buschhaus MS Graham PM Semiao CJ Semproni SP Kim SJ Legzdins P 《Journal of the American Chemical Society》2008,130(11):3652-3663
Thermolysis of Cp*W(NO)(CH2CMe3)(eta(3)-CH2CHCHMe) (1) at ambient temperatures leads to the loss of neopentane and the formation of the eta(2)-diene intermediate, Cp*W(NO)(eta(2)-CH2=CHCH=CH2) (A), which has been isolated as its 18e PMe3 adduct. In the presence of linear alkanes, A effects C-H activations of the hydrocarbons exclusively at their terminal carbons and forms 18e Cp*W(NO)(n-alkyl)(eta(3)-CH2CHCHMe) complexes. Similarly, treatments of 1 with methylcyclohexane, chloropentane, diethyl ether, and triethylamine all lead to the corresponding terminal C-H activation products. Furthermore, a judicious choice of solvents permits the C-H activation of gaseous hydrocarbons (i.e., propane, ethane, and methane) at ambient temperatures under moderately elevated pressures. However, reactions between intermediate A and cyclohexene, acetone, 3-pentanone, and 2-butyne lead to coupling between the eta(2)-diene ligand and the site of unsaturation on the organic molecule. For example, Cp*W(NO)(eta(3),eta(1)-CH2CHCHCH2C(CH2CH3)2O) is formed exclusively in 3-pentanone. When the site of unsaturation is sufficiently sterically hindered, as in the case of 2,3-dimethyl-2-butene, C-H activation again becomes dominant, and so the C-H activation product, Cp*W(NO)(eta(1)-CH2CMe=CMe2)(eta(3)-CH2CHCHMe), is formed exclusively from the alkene and 1. All new complexes have been characterized by conventional spectroscopic and analytical methods, and the solid-state molecular structures of most of them have been established by X-ray crystallographic analyses. Finally, the newly formed alkyl ligands may be liberated from the tungsten centers in the product complexes by treatment with iodine. Thus, exposure of a CDCl3 solution of the n-pentyl allyl complex, Cp*W(NO)(n-C5H11)(eta(3)-CH2CHCHMe), to I2 at -60 degrees C produces n-C5H11I in moderate yields. 相似文献
9.
A novel series of ionic Ru(II) arene Cp* sandwich complexes has been synthesized and characterized. Screening results for cytotoxicity against a range of human tumor cell lines and normal human cells indicate that the complexes show promising anticancer activity, which varies with changes in the arene ligand and the anionic counterion. 相似文献
10.
The pnictocenium salts [Cp*PCl]+[μCl]? ( 1 a ), [Cp*PCl]+[ClAl(ORF)3]? ( 1 b ), [Cp*AsCl]+[ClAl(ORF)3]? ( 2 ), and [(Cp*)2P]+[μCl]? ( 3 ), in which Cp*=Me5C5, μCl=(FRO)3Al? Cl? Al(ORF)3, and ORF=OC(CF3)3, were prepared by halide abstraction from the respective halopnictines with the Lewis superacid PhF→Al(ORF)3. 1 The X‐ray crystal structures of 1 a , 2 , and 3 established that in the half as well as in the sandwich cations the Cp* rings are attached in an η2‐fashion. By using one or two equivalents of the Lewis acid, the two new weakly coordinating anions [μCl]? and [ClAl(ORF)3]? resulted. They also stabilize the highly reactive cations in PhF or 1,2‐F2C6H4 solution at room temperature. The chloride ion affinities (CIAs) of a range of classical strong Lewis acids were also investigated. The calculations are based on a set of isodesmic BP86/SV(P) reactions and a non‐isodesmic reference reaction assessed at the G3MP2 level. 相似文献
11.
Large Spin‐Relaxation Barriers for the Low‐Symmetry Organolanthanide Complexes [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb,Dy)
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Dr. Selvan Demir Dr. Joseph M. Zadrozny Prof. Dr. Jeffrey R. Long 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(31):9524-9529
Single‐molecule magnets comprising one spin center represent a fundamental size limit for spin‐based information storage. Such an application hinges upon the realization of molecules possessing substantial barriers to spin inversion. Axially symmetric complexes of lanthanides hold the most promise for this due to their inherently high magnetic anisotropies and low tunneling probabilities. Herein, we demonstrate that strikingly large spin reversal barriers of 216 and 331 cm?1 can also be realized in low‐symmetry lanthanide tetraphenylborate complexes of the type [Cp*2Ln(BPh4)] (Cp*=pentamethylcyclopentadienyl; Ln=Tb ( 1 ) and Dy ( 2 )). The dysprosium congener showed hysteretic magnetization data up to 5.3 K. Further studies of the magnetic relaxation processes of 1 and 2 under applied dc fields and upon dilution within a matrix of [Cp*2Y(BPh4)] revealed considerable suppression of the tunneling pathway, emphasizing the strong influence of dipolar interactions on the low‐temperature magnetization dynamics in these systems. 相似文献
12.
Redox addition of the Pd-Pd bond in [Pd(2)Cl(2)(dppm)(2)] across S-S or Se-Se bond in [Pt(X(4)-kappa(2)X(1),X(4))(P-P)] (X = S, Se; P-P = dppe or 2 x PPh(3); dppm = bis(diphenylphosphino)methane, dppe = bis(diphenylphosphino)ethane) leads to the isolation of [PtPd(2)(mu(3)-X)(2)(P-P)(dppmX-kappa(2)X,P(4))(2)](2+) and represents an atom-economy process that converts chalcogen-rich complexes to heterometallic chalcogenide aggregates. Activation of the [PtX(4)] ring is achieved by tetrachalcogenide reduction and dual oxidation of palladium and phosphine. 相似文献
13.
Chen Y Zhou Y Chen P Tao Y Li Y Qu J 《Journal of the American Chemical Society》2008,130(46):15250-15251
The reactions of [Cp*Fe(mu-SR1)3FeCp*] (Cp* = eta5-C5Me5; R1 = Et, Me) with 1.5 equiv R2NHNH2 (R2 = Ph, Me) give the mu-eta2-diazene diiron thiolate-bridged complexes [Cp*Fe(mu-SR1)2(mu-eta2-R2N NH)FeCp*], along with the formation of PhNH2 and NH3. These mu-eta2-diazene diiron thiolate-bridged complexes exhibit excellent catalytic N-N bond cleavage of hydrazines under ambient conditions. 相似文献
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三齿配体三(2-巯基-1-甲基咪唑)硼酸盐[TmMe]K与含有半夹心结构金属铱和铑化合物[Cp*Ir(μ-Cl)Cl]2和[Cp*Rh(μ-Cl)Cl]2反应形成具有18电子结构的配合物[Cp*Ir(TmMe)]Cl(1)和[Cp*Rh(TmMe)]Cl(2).所有的化合物都经过IR,NMR和EA表征,并通过X-射线衍射单晶结构分析测定了配合物2的分子结构. 相似文献
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Reactions of Cp*NbCl4 and Cp*TaCl4 with Trimethylsilyl‐azide, Me3Si‐N3. Molecular Structures of the Bis(azido)‐Oxo‐Bridged Complexes [Cp*NbCl(N3)(μ‐N3)]2(μ‐O) and [Cp*TaCl2(μ‐N3)]2(μ‐O) (Cp* = Pentamethylcyclopentadienyl) The chloro ligands in Cp*TaCl4 (1c) can be stepwise substituted for azido ligands by reactions with trimethylsilyl azide, Me3Si‐N3 (A) , to generate the complete series of the bis(azido)‐bridged dimers [Cp*TaCl3‐n(N3)n(μ‐N3)]2 ( n = 0 (2c) , n = 1 (3c) , n = 2 (4c) and n = 3 (5c) ). If the solvent CH2Cl2 contains traces of water, an additional oxo bridge is incorporated to give [Cp*‐TaCl2(μ‐N3)]2(μ‐O) (6c) or [Cp*TaCl(N3)(μ‐N3)]2(μ‐O) (7c) , respectively. Both 6c and 7c are also formed in stoichiometric reactions from [Cp*TaCl2(μ‐OH)]2(μ‐O) (8c) and A . Analogous reactions of Cp*NbCl4 (1b) with A were used to prepare the azide‐rich dinuclear products [Cp*NbCl3‐n(N3)n(μ‐N3)]2 (n = 2 (4b) , and n = 3 (5b) ), and [Cp*NbCl(N3)(μ‐N3)]2(μ‐O) (7b) . The mononuclear complex Cp*Ta(N3)Me3 (10c) is obtained from Cp*Ta(Cl)Me3 and A . All azido complexes were characterised by their IR as well as their 1H and 13C NMR spectra; X‐ray crystal structure analyses are available for 6c and 7b . 相似文献
18.
Kou HZ Tang JK Liao DZ Gao S Cheng P Jiang ZH Yan SP Wang GL Chansou B Tuchagues JP 《Inorganic chemistry》2001,40(19):4839-4844
Two bimetallic assemblies, [Ni(tn)(2)](2)[Cr(CN)(5)(NO)]OH.H(2)O (1) and [Ni(tn)(2)](2)[Co(CN)(6)]NO(3).2H(2)O (2) (tn = 1,3-diaminopropane), have been prepared and structurally and magnetically characterized. Crystal data for 1 (2): space group P1 (P1), a = 8.698(3) (8.937(2)) A, b = 10.001(2) (9.863(1)) A, c = 10.158(2) (10.064(1)) A, alpha = 87.40(2) (86.064(10)) degrees, beta = 65.10(2) (65.489(10)) degrees, gamma = 81.63(2) (81.572(12)) degrees and Z = 1 (1). Both structures consist of two-dimensional grid-like polycations containing Ni-N triple bond C-M linkages (M = Cr or Co) and counteranions (OH, NO(3)). Magnetic studies of 1 showed that the complex displays a metamagnetic behavior originating from intralayer ferromagnetic and interlayer antiferromagnetic interactions. Long-range antiferromagnetic ordering was observed at T(N) = 3.3 K. Complex 2 exhibits intramolecular ferromagnetic interactions through the diamagnetic N triple bond C-Co-N triple bond C bridges, owing to superexchange involving the empty d(sigma) orbital of the diamagnetic Co(III) ion. 相似文献
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Polycarborane-substituted molecules [Cp*Rh{E 2C 2(B 10H 10)}] 3(tpst) [E = S ( 2a), Se ( 2b)] were synthesized and characterized. 2a and 2b form toluene solvates in the solid state showing infinitely connected [( 2a, b)-(toluene)] infinity helices. The chains of these supramolecules are held together by Cp*-toluene-Cp* pi-stacking interactions of two of the three Cp* ligands of the bell-shaped 2a and 2b molecules. Unconventional BH (delta-)-pyridyl (delta+) aromatic hydrogen bonding enforces the bell-shapes of the molecular units, and the Cp* conformations are expected to induce the supramolecular structures. 相似文献