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1.
Compounds 2CuCl · DADS (I) and 2CuBr · DADS (II) (DADS is diallyl disulfide) are prepared by the ac electrochemical synthesis, and their crystal structures are determined. The complexes are isostructural, space group P21/n, Z = 4; I: a = 8.995(2) Å, b = 12.541(2) Å, c = 9.644(2) Å, β = 98.74(2)°, V = 1075.3(4) Å3, II: a = 9.064(2), b = 12.878(3), c = 9.832(2) Å, β = 98.61(3)°, V = 1134.7(4) Å3. In complexes I and II, the tetradentate DADS ligand is chelate-bridging and is coordinated by two crystallographically independent copper atoms of two inorganic Cu4X4 fragments. An insignificantly distorted tetrahedral environment of each of the two copper atoms consists of the olefin group, sulfur atom, and two halogen atoms. The complexes are stabilized additionally by the formation of C-H?S hydrogen bonds involved in characteristic seven-membered rings in the structures.  相似文献   

2.
Asymmetric telechelic polyisobutylene, α-PIB-ω), carrying the olefinic head group α = (CH3)2 C[dbnd]CHCH2- and tertiary chlorine endgroup ω = -C(CH3)2Cl has been synthesized by the use of the (CH3)2C[dbnd]CHCH2Cl/BCl3 initiating system. Highest yields were obtained by using methylene chloride diluent at about ?50°C. The presence and position of the olefinic head-group was proven by epoxidation/titration and epoxidation/cleavage. The presence and position of a tertiary chlorine endgroup was proven by initiating block polymerization of a second monomer, such as styrene or α-methylstyrene, by using the asymmetric telechelic polyisobutylene prepolymer in conjunction with Et2AlCl coinitiator. According to I/DP versus 1/[M] plots obtained in model block copolymerization experiments, with the use of the tert-BuCl/Et2AlCl initiating system at ?30°C, significant chain transfer to monomer occurs during blocking of styrene; however, monomer transfer is negligible during blocking of α-methylstyrene. Thus, under suitable conditions head-functionalized block copolymers (CH3)2C[dbnd]CHCH2-PIB-b-PαMeSt virtually free of homopolymer contaminants can be obtained.  相似文献   

3.
The migration of the double bond in the allylcarboxamide ligands of (μ-H)Os3(μ-O=CN RCH2CH=CH2) (CO)10 (R=H (1) or CH3 (2)), (μ-D)Os3(μ-O=CNDCH2CH=CH2) (CO)10, and (μ-H)Os3(μ-O=CNHCD2CH=CH2)(CO)10 clusters was studied by1H,2H, and13C NMR spectroscopy. Neither μ-D nor ND groups in the deuterated complexes are directly involved in prototropic processes of allylic rearrangement. Initially, the deuterium atom of the CD2 group migrates to the ψ-carbon atom of the allyl fragment to form the −CD=CH-CH2D propenyl moiety, in which the deuterium and hydrogen atoms are gradually redistributed between the ψ-and β-carbon atoms. The triosmium cluster complexes containing the bridging carboxamide ligands O=CNRR' catalyze the allylic rearrangement ofN-allylacetamide. Based on the data obtained, the probable scheme of the allylic rearrangements in clusters1 and2 was proposed. Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 11, pp. 2182–2186, November, 1999.  相似文献   

4.
5.
The heteroelement-containing alkylidene imide complexes with molybdenum and tungsten Et3SiCH=Mo(NAr)(OR)2 (I), Et3 ECH=W(NAr)(OR)2 (E = Si (II), Ge (III); Ar = 2,6-i-Pr2C6H3; R=CMe2 CF3) and π-complex (RO)2(ArN)Mo(CH2=CH-GeEt3) (IV) were synthesized by the reaction of Alkyl-CH=M(NAr) (OR)2 (M=Mo, W; Alkyl = t-Bu, PhMe2C) with organosilicon and organogermanium vinyl reagents Et3ECH=CH2 (E = Si, Ge). The structure of compounds I–III was determined by X-ray diffraction (XRD). The complexes I–IV are active initiators of metathesis polymerization of cycloolefins.  相似文献   

6.
Two new supramolecular compounds,2C 10 H 9 N 2 + ·C 8 HF 4 O 4 2-·C 8 H 2 F 4 O 4 /(H 2 tfbdc)· (tfbdc)·(Hbipy) 2 (1) and C 4 H 6 N 2 2+ ·C 8 HF 4 O 4 2-/(tfbdc)·(H 2 pz) (2),were synthesized and characterized by elemental analysis,IR spectra,and single-crystal X-ray diffraction.Compound 1 crystallizes in the triclinic system,space group P1,with a=8.3453(12),b=10.1798(15),c=10.6626(16),α=87.591(2),β=74.047(2),γ=69.006(2)°,V=834.53(12) 3,D c=1.614 g/cm 3,F(000)=400,u=1.45 cm-1,Z=2,the final R=0.0353 and wR=0.1005 for 5882 observed reflections with I > 2σ(I);and compound 2 crystallizes in the monoclinic system,space group P2 1 /c,with a=10.471(4),b=5.4419(19),c=12.249(4),β=114.909(6)°,V=633(4)3,D c=1.669 g/cm 3,F(000)=320,u=1.63 cm-1,Z=2,the final R=0.0794 and wR=0.2923 for 3213 observed reflections with I > 2σ(I).Both compounds 1 and 2 crystallize as charge-transfer organic salts with the dianionic or neutral acid components lying at the inversion centers.Hbipy + cations and anionic acid in compound 1 are linked to form a chain by means of C-H···O hydrogen bonds.Adjacent chains are further extended into a two-dimensional layer network via N-H···O and O-H···N hydrogen bonds.In compound 2,the acid and base subunits are arranged alternately to generate a linear tape motif via N-H O hydrogen bonds;these tapes are further combined into a three-dimensional array with CdSO 4 topology via C-H O intermolecular hydrogen bonds.  相似文献   

7.
The dependence of the properties of mixed ligand [Ni(II)(2)L(μ-O(2)CR)](+) complexes (where L(2-) represents a 24-membered macrocyclic hexaamine-dithiophenolato ligand) on the basicity of the carboxylato coligands has been examined. For this purpose 19 different [Ni(II)(2)L(μ-O(2)CR)](+) complexes (2-20) incorporating carboxylates with pK(b) values in the range 9 to 14 have been prepared by the reaction of [Ni(II)(2)L(μ-Cl)](+) (1) and the respective sodium or triethylammonium carboxylates. The resulting carboxylato complexes, isolated as ClO(4)(-) or BPh(4)(-) salts, have been fully characterized by elemental analyses, IR, UV/vis spectroscopy, and X-ray crystallography. The possibility of accessing the [Ni(II)(2)L(μ-O(2)CR)](+) complexes by carboxylate exchange reactions has also been examined. The main findings are as follows: (i) Substitution reactions between 1 and NaO(2)CR are not affected by the basicity or the steric hindrance of the carboxylate. (ii) Complexes 2-20 form an isostructural series of bisoctahedral [Ni(II)(2)L(μ-O(2)CR)](+) compounds with a N(3)Ni(μ-SR)(2)(μ-O(2)CR)NiN(3) core. (iii) They are readily identified by their ν(as)(CO) and ν(s)(CO) stretching vibration bands in the ranges 1684-1576 cm(-1) and 1428-1348 cm(-1), respectively. (iv) The spin-allowed (3)A(2g) → (3)T(2g) (ν(1)) transition of the NiOS(2)N(3) chromophore is steadily red-shifted by about 7.5 nm per pK(b) unit with increasing pK(b) of the carboxylate ion. (v) The less basic the carboxylate ion, the more stable the complex. The stability difference across the series, estimated from the difference of the individual ligand field stabilization energies (LFSE), amounts to about 4.2 kJ/mol [Δ(LFSE)(2,18)]. (vi) The "second-sphere stabilization" of the nickel complexes is not reflected in the electronic absorption spectra, as these forces are aligned perpendicularly to the Ni-O bonds. (vii) Coordination of a basic carboxylate donor to the [Ni(II)(2)L](2+) fragment weakens its Ni-N and Ni-S bonds. This bond weakening is reflected in small but significant bond length changes. (viii) The [Ni(II)(2)L(μ-O(2)CR)](+) complexes are relatively inert to carboxylate exchange reactions, except for the formato complex [Ni(II)(2)L(μ-O(2)CH)](+) (8), which reacts with both more and less basic carboxylato ligands.  相似文献   

8.
Three new tin coordination compounds (4,4'-Hbipy)2[Sn2(C2O4)3] ( 1 ), (4,4'-H2bipy)[Sn(C2O4)2] ( 2 ), and SnCl2(4,4'-bipy) ( 3 ) were synthesized under hydro-(solvo-)thermal conditions and their crystal structures were determined by single-crystal X-ray diffraction. Compound 1 exhibits a ionic structure based on discrete [4,4'-Hbipy]+ cations and [Sn2(C2O4)3]2– anions. These two units are linked via N–H ··· O hydrogen bonds to form a pseudo-one-dimensional zigzag hydrogen-bonded chain. In compound 2 , four-coordinate Sn atoms form monomeric tin dioxalato complexes, which are connected to the doubly protonated [4,4'-H2bipy]2+ cations through N–H ··· O hydrogen bonded to give a one-dimensional zigzag hydrogen-bonded chain. Compound 3 forms a three-dimensional hydrogen-bonded network, in which 1[SnCl2(4,4'-bipy)] linear chains are interconnected to each other by C–H ··· Cl hydrogen bonding. The solid-state UV/Vis/NIR diffuse reflectance spectroscopy shows that three compounds are broadband semiconductors. The thermogravimetric analysis evidences the thermal stability of the three compounds up to 175, 201, and 246 °C, respectively.  相似文献   

9.
1 INTRODUCTION The pyridyl-phosphine ligands have been widely used for many years to synthesize hetero- or homo-nuclear metal complexes[1], as electronic differentiation associated with the hard (N) and soft (P) donor atoms dictates their unique reactivities and coordination modes. One of the most common pyridylphosphines studied to date is (2-C5H4N)PPh2 which displays numerous ligating modes ranging from P-coordination and P,N-chelation to the more common P,N-bridging of two metal …  相似文献   

10.
The preparation and characterization of the compounds trans-M(2)(T(i)PB)(2)(O(2)C-CH=CH-2-C(4)H(3)S)(2) where M = Mo or W and T(i)PB = 2,4,6-triisopropylbenzoate are reported. The optical spectra of the new compounds are compared with those of related trans-M(2)(T(i)PB)(2)L(2) compounds where L = O(2)C-C(6)H(4)-4-CN, O(2)C-α,α'-terthienyl (TTh), and O(2)C-4-C(6)H(4)N-B(C(6)F(5))(3), that show strong metal-to-ligand charge transfer bands because of M(2)δ to Lπ conjugation, and are notably temperature dependant due to the various conformations of the two trans-L groups. Upon cooling the spectral features sharpen as the planar geometry that optimizes M(2)δ-Lπ conjugation is favored. As the electronic coupling of the two trans-Lπ systems increases the (0,0) electronic transition gains intensity indicating a greater nesting of the ground state (S(0)) and excited state (S(1)) potential energy surfaces. These features are discussed in terms of the related electronic coupling of [M(2)]-[M(2)] complexes.  相似文献   

11.
Summary The complex [Rh2Cl2(-CO)(-vdpp)2] (1) (vdpp=H2C=C(PPh2)2) was prepared by reaction of [Rh2(CO)4-(-Cl)2] with vdpp. When (1) is allowed to stand overnight under an atmosphere of CO without stirringtrans-[Rh2Cl2(CO)2(-vdpp)2] is formed as a red precipitate in low yields. On rapid addition of CO the tricarbonyl complex [Rh2(CO)2(-CO)(-Cl)(-vdpp)2]-Cl is formed instead. The chemical behaviour of the vdpp-substituted complex (1) is very similar to that of the corresponding dppm-substituted complex [Rh2(Cl2-(-CO)(-dppm)2] (dppm=H2C(PPh2)2). this similarity also extends to the molecular structures of both compounds. Unit cell parameters of (1): space group Pben (Z=8),a=2344.7(5),b=1506.9(7),c=3021.6(9)pm. Rh-Rh 267.4(1) pm.  相似文献   

12.
《Chemical physics letters》1999,291(5-6):321-326
The mono-anion, di-anion and tri-anion of dicyanodihydrofullerene [C60(CN)2] have been generated and monitored with a thin-layer spectro-electrochemical cell. The characteristic NIR absorption bands are found to be at 1019, 875 as well as at 744, and 691 nm for C60(CN)2, C60(CN)22− and C60(CN)23−, respectively. Density functional theory calculations indicate that these anions exhibit no Jahn–Teller effect and possess charge distributions and shape distortions that are different from C60n(n=1,2,3) upon negative charge addition.  相似文献   

13.
Two novel examples of sandwich type heteropolyanions were synthesized and characterized by X-ray crystal structure and elemental analysis as well as infrared spectroscopy. Na13[H3Cu4(H2O)2(CuW9O34)2]39H2O (1) and Na9K[Fe4(H2O)2(FeW9O34)2]32H2O (2) were prepared in aqueous solution by reaction of sodium tungstate with FeIII and CuII cations, respectively. 1 crystallizes in the monoclinic space group P21/n (a=13.054(3) Å, b=17.729(4) Å, c=20.998(4) Å, =93.50(3)°), while 2 is triclinic, space group P¯1 (a=12.316(2) Å, b=13.716(3) Å, c=14.925(3) Å, =99.36(3)°, =104.21(3)°, =101.55(3)°). Each anion consists of two [XW9O34] n moieties (X=FeIII, n=11 (1) and CuII, n=12 (2)) which can be described as -B-isomers of the defect Keggin anion. These units are linked via a belt of four FeIIIO6 or CuIIO6 groups. Two transition metal atoms fill their octahedral coordination sphere with one additional water ligand.  相似文献   

14.
《Polyhedron》1987,6(6):1483-1489
The complexes Re2Br4(depe)2 and Re2X4(dppee)2 (X = Cl or Br, depe = Et2PCH2CH2PEt2, dppee = cis-Ph2PCHCHPPh2) have been prepared in their α- (eclipsed rotational geometry, chelating phosphine ligands) and β- (staggered rotational geometry, bridging phosphine ligands) isomeric forms. The chloro complex β-Re2Cl4(depe)2 has also been isolated. In the case of α- and β- Re2Br4(depe)2, the preparations involve the reactions of Re2Br4(P-n-Pr3)4 with depe in toluene-ethanol. While α-Re2X4(dppee)2 are prepared from the reactions of (n-Bu4N)2Re2X8 with dppee in various solvents, the β-isomers are obtained upon reacting Re2X4(PR3)4 (R = Et or n-Pr) with dppee in benzene. These are the first examples of triply bonded dirhenium(II) complexes that have been isolated in both their α- and β-forms. β-Re2X4(dppee)2 (X = Cl or Br) constitute the first examples of complexes of this structural type which contain both CC and MM units within the same fused decalin-like ring system. The isomers β-Re2Cl4(depe)2 and β-Re2X4(dppee)2 (X = Cl or Br) are oxidized by NOPF6 in acetonitrile to give paramagnetic β-[Re2Cl4(depe)2]PF6 and β-[Re2X4(dppee)2]PF6. These oxidized complexes in turn react with CH3CN in the presence of T1PF6 to afford β-[Re2Cl3(depe)2(NCMe)](PF6)2 and β-[Re2X3(dppee)2(NCMe)](PF6)2, respectively. The cleavage of the ReRe bonds of α- and β-Re2Cl4(dppee)2 occurs upon their reaction with CCl4-CH2Cl2 to give cis-ReCl4(dppee). The related bromo complex cis-ReBr4(dppee) is formed when β-Re2Br4(dppee)2 is reacted with CH2Cl2-Br2.  相似文献   

15.
A Ni(Ⅱ) complex [Ni(bdpm)2(OAc)]2(N3)2·5H2O (bdpm = bis(3,5-dimethylpyrazol-1-yl)-methane) was synthesized and characterized by elemental analysis, IR and single-crystal X-ray diffraction. It crystallizes in the monoclinic system, space group P21/c with a = 18.630(2), b =16.6624(19), c = 19.821(2) (A), β = 90.146(2)°, V = 6152.9(12) (A)3, Z = 4, C48H8oN22Ni2O9, Mr =1226.76, Dc = 1.324 g/cm3, F(000) = 2600 andμ = 0.680 mm-1. The structure was refined to the final R = 0.0578 and wR = 0.1337 for 10848 independent reflections (Rint = 0.0311) and 6915 observed reflections (I > 2σ(Ⅰ)). The complex contains two asymmetric molecules in the cell with small difference in bond distances and bond angles. Each Ni(Ⅱ) ion is bound by four nitrogen atoms of two chelating bdpm groups in a six-membered boat conformation and two oxygen atoms from one chelating bidentate acetate group to form a distorted octahedral geometry. The complex also contains azide anion outside acting as counteranion and two crystalline water molecules to link two discrete mononuclear cations though hydrogen bonds.  相似文献   

16.
Reaction of [Et4N]2[Mo2S2(μ-S)2(edt)2] with CoCl2(6H2O and Phen in MeCN followed by recrystallization in DMSO/Et2O gave rise to dark-red block crystals of {[Co(Phen)3]- [Mo2S2(μ-S)2(edt)2]}2·(DMSO)2·(Et2O) 1 (C88H86Co2Mo4N12O3S18). 1 crystallizes in the monoclinic system, space group P21/c with a = 24.631(4), b = 16.117(3), c = 24.791(4) (A), β = 92.835°, V = 9829.3(3) (A)3, Z = 4, Mr = 2438.57, Dc = 1.648 g/cm3, F(000) = 4928, μ = 12.61 cm-1, R = 0.0936 and wR = 0.1682 for 12998 observed reflections with I > 2.0σ(I). In the structure of 1, the Co atom of the [Co(Phen)3]2+ dication is octahedrally coordinated by three Phen ligands. The Mo atom of the [Mo2S2(μ-S)2(edt)2]2- dianion is coordinated by two μ-S, one terminal S and two S atoms from edt, forming a distorted square pyramidal geometry. The mean Co-N and Mo…Mo bond distances are 2.139 and 2.872 (A), respectively.  相似文献   

17.
The geometries, stabilities, electronic, and magnetic properties of AunSc clusters have been systematically investigated by density functional theory. The lowest energy structures of AunSc favor planar structure and the doped Sc atom does not disturb the frame of Aunclusters with n≤11. For n≥12, Sc atom is fully encapsulated by the Au cages. From theanalysis of the second-order energy difference, the fragmentation energies, vertical ionizationpotential, vertical electron affinity, and HOMO-LUMO gap, the clusters with odd Au atoms possess relatively higher stabilities than their neighbor size. The doping of Sc atom can greatly improve the stability and change the sequence of chemical activity for Aun. For n≤11, the total magnetic moments of AunSc appear the alternation between 0.00 and 1.00 μB. The total magnetic moments are quenched when Sc is trapped into the Au cages with n≥12.  相似文献   

18.
The salts [RuII(L–L)3](CF3SO3)2 (L–L = bpy or phen) have been prepared in high yields via reactions of [RuII(DMF)6](CF3SO3)2 (DMF = N,N-dimethylformamide), generated in situ by reduction of [RuIII(DMF)6]-(CF3SO3)3, with an excess of bpy or phen at room temperature in DMF solutions.  相似文献   

19.
The reactions of the electron-rich triply bonded dirhenium(II) complex Re2Cl4(-dcpm)2 (dcpm=Cy2PCH2PCy2) with the isocyanide ligands XylNC (Xyl=2,6-dimethylphenyl) and t-BuNC afford the complexes Re2Cl4(-dcpm)2(CNXyl) and Re2Cl4(-dcpm)2(CN-t-Bu)2 which in turn react with CO to give salts of the [Re2Cl3(-dcpm)2(CO)2(CNXyl)]+ and [Re2Cl3(-dcpm)2(CN-t-Bu)2(CO)]+ cations which exist in different isomeric forms. This chemistry is compared with that developed previously for the analogous complexes derived from Re2Cl4(-dppm)2.  相似文献   

20.
1INTRODUCTIONRecently,therehasbeenconsiderableinterestinthelanthanide(III)hexacyanoferrates,theanalogoushexacyanocobaltateandhexacyanochromiumatecom-plexesbecauseoftheirpotentialapplicationsascata-lyticandsemi-conductivematerials.InitialstudiesofmetalhexacyanocobaltateswerecarriedoutbyJa-mesandWilland[1]whoreportedtheamountofhy-drationassociatedwithmicroscopiccrystalsofsever-allanthanidecomplexes.FurtherBonnetandParis[2]studiedtheLNCo(CN)6?nH2Oseries(n=4)byusinginfraredandX-raymethod…  相似文献   

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