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1.
The trimetallic cluster W2CuAgS4(TDT)2(PPh3)2-CH2Cl2 (TDT= [S2(C6H3)CH3]2-) (2) has been prepared from the reaction of the well-defined molecule building block [W2S4(TDT)2]2-(1) with AgNO3,CuBr and PPh3.The structure contains a [W2CuAgS4]4+ distorted cubane-like core.Two types of metal-metal bonds exist in the core.One is W-W bond of which length is 0.2871(1) nm,the other is W-M' (M'=Cu or Ag) bonds,whose mean distance is 0.2980 nm.The details of synthesis,structure,IR,UV-Vis and 31P NMR spectra are reported.The crystallographic data are:space group F21/n,with 0=1.6987(4),6=1.7763(6),c=1.8918(5) nm,β=98.54(2)°,V=5.645(3) nm3,Z=4,and final R=0.043 for 6437 observed reflections.  相似文献   

2.
Synthesis and Crystal Structures of (PPh4)2[TeS3] · 2 CH3CN and (PPh4)2[Te(S5)2] (PPh4)2[TeS3] · 2 CH3CN was obtained by the reaction of PPh4Cl, Na2S4 and Te in acetonitrile. With sulfur it reacts yielding (PPh4)2[Te(S5)2]. The crystal structures of both products were determined by X-ray diffraction. (PPh4)2[TeS3] · 2 CH3CN: triclinic, space group P1 , Z = 2, R = 0.041 for 4 629 reflexions; it contains trigonal-pyramidal [TeS3]2? ions with an average Te? S bond length of 233 pm. (PPh3)2[Te(S5)2]: monoclinic, P21/n, Z = 2, R = 0.037 for 2 341 reflexions. In the [Te(S5)2]2? ion the tellurium atom has a nearly square coordination by four S atoms. Along with the Te atoms each of the two S5 groups forms a ring with chair conformation.  相似文献   

3.
Two novel heterometallic trinuclear incomplete cubane-like clusters [(CH3CH2)4N][{M2CuS4}(edt)2(PPh3)] (M = Mo, W) have been synthesized by reaction of [(CH3CH2)4N]2[M2S4(edt)2] (M = Mo, W) with Cu(PPh3)2(dtp) [where edt is 1,2-ethane-dithiolato ligand, dtp is S2P(OCH2CH3)2]. The two crystals are isomorphous in space group P1 (No. 1). The unit cell contains two independent molecules, but the two discrete anions have the same orientation for the PPh3 ligands along one axis so the space group is undoubtedly non-centrosymmetric. The discrete anion contains two edt ligands and one PPh3 ligand attached to one incomplete cubane-like cluster core {M2CuS4}3+ (M = Mo, W). The bond lengths of Mo---Mo[W---W] and the two Mo---Cu[W-Cu] are 2.852(2)[2.844(1)], 2.802(2)[2.765(3)], 2.760(2)[2.762(3)] Å, respectively. The M 2S4(edt)2 (M = Mo, W) moiety remains almost unchanged, except that for the compound 1 the Mo=S double bond length elongates from av. 2.10 to av. 2.165 Å. The title clusters provide a new type of unsymmetric μ2-bridging sulphido ligand. The incomplete cubane-like cluster core {Mo2CuS4}3+ of compound 1 is distorted because the two Cu---μ2---S bond lengths are significantly different (2.313 Å and 2.409 Å), but the core {W2CuS4}3+ of compound 2 has approximately Cs symmetry. The IR spectra of the two title clusters and two starting materials are assigned.  相似文献   

4.
Two triangular molybdenum‐tellurium clusters, Mo3Te7‐[S2CN (CH2CH2OH2]3I (1) and Mo3Te4Y3[S2P(iPrO)2]3I (Y3 = 1. 43Te+ 1.57S) (2), were obtained from the reaction of K · HOdtc [HOdtc = S2CN(CH2CH2OH)2] or K·iPr2dtp (iPr2dtp = S2P[OCH(CH3)2]2) with a mixed product of elements Mo, Te(S) and I2 at high temperature. The structures of the two compounds were determined by X‐ray crystallography study. Crystal data are, (1): monoclinic, P21/n, a = 1.6256(3), b = 1.3264(2), c = 1.8808(4) nm, β=96.923°, V = 4.025.9 (14) nm3, Dcal = 3.050g·cm‐3, Z = 4, and (2): monoclinic, P21/n, a = 1.4564(2), b = 2.3917(4), c = 1.5094(3) nm, β = 114.35(2)°, V = 4.0259(14) nm3, Dcal = 2.449 g·cm?3 and Z = 4. Single crystal analyses show that 1 consists of discrete Mo3Te7[S2CN(CH2CH2OH)2]3I connected into three‐dimensional framework via hydrogen bonds, while 2 forms a linear chain via Te(S)—I interaction.  相似文献   

5.
Reactions of S4N4 with diphosphines, Ph2P(X)PPh2 (X = NC4H8N, CH2CH2) have resulted in the isolation of N3S3? NPPh2(X)Ph2PN? S3N3 (X = NC4H8N, CH2CH2), (S)PPh2(CH2CH2)Ph2PN? S3N3, and (S)PPh2NC4H8NPh2P(S) as new compounds. These heterocycles have been characterized by analytical and spectroscopic (IR, UV-VIS, 1H and 31P-NMR, and MS) techniques.  相似文献   

6.
Six heterothiometalic clusters, namely, [WS4Cu4(dppm)4](ClO4)2 · 2DMF · MeCN ( 1 ), [MoS4Cu4(dppm)4](NO3)2 · MeCN ( 2 ) [MoS4Cu3(dppm)3](ClO4) · 4H2O ( 3 ), [WS4Cu3(dppm)3](NO3) · 4H2O ( 4 ), [WS4Cu3(dppm)3]SCN · CH2Cl2 ( 5 ), and [WS4Cu3(dppm)3]I · CH2Cl2 ( 6 ) [dppm = bis (diphenylphosphanyl)methane] were synthesized. Compounds 1 – 4 were obtained by the reactions of (NH4)2MS4 (M = Mo, W) with [Cu22‐dppm)2(MeCN)2(ClO4)2] {or [Cu(dppm)(NO3)]2} in the presence of 1,10‐phen in mixed solvent (CH3CN/CH2Cl2/DMF for 1 and 2 , CH2Cl2/CH3OH/DMF for 3 and 4 . Compounds 5 and 6 were obtained by one‐pot reactions of (NH4)2WS4 with dppm and CuSCN (or CuI) in CH2Cl2/CH3OH. These clusters were characterized by single‐crystal X‐ray diffraction as well as IR, 1H NMR, and 31P NMR spectroscopy. Structure analysis showed that compounds 1 and 2 are “saddle‐shaped” pentanuclear cationic clusters, whereas compounds 3 – 6 are “flywheel‐shaped” tetranuclear cationic clusters. In 1 and 2 , the MS42– unit (M = W, Mo) is coordinated by four copper atoms, which are further bridged by four dppm molecules. In compounds 3 – 6 , the MS42– unit is coordinated by three copper atoms and each copper atom is bridged by three dppm ligands.  相似文献   

7.
Chalcogenoniobates as Reagents for the Synthesis of New Heterobimetallic Niobium Coinage Metal Chalcogenide Clusters In the presence of phosphine chalcogenoniobates such as Li3[NbS4] · 4 CH3CN ( I ), (NEt4)4[Nb6S17] · 3 CH3CN ( II ) and (NEt4)2[NbE′3(EtBu)] ( III a : E′ = E = S; III b : E = Se, E′ = S; III c : E = E′ = Se) respectively react with copper and gold salts to give a number of new heterobimetallic niobium copper(gold) chalcogenide clusters. These clusters show metal chalcogenide units already known from the complex chemistry of the tetrachalcogenometalates [ME4]n (M = V, n = 3, E = S; M = Mo, W, n = 2, E = S, Se). The compounds 1 – 8 owe a central tetrahedral [NbE4] structural unit, which coordinates η2 from two to five coinage metal atoms, employing the chalcogenide atoms of the [NbE4] edges. The compounds 9 – 11 have a [M′2Nb2E4] (M′ = Cu, Au) heterocubane unit in common, involving a metal metal bond between the niobium atoms, while the compounds 12 and 13 show a complete and 14 an incomplete [M′3NbE3X] heterocubane structure (X = Cl, Br). 15 consists of a Cu6Nb2 cube with the six planes capped by μ4 bridging selenide ligands forming an octahedra. The compounds 1 – 15 are listed below: (NEt4) [Cu2NbSe2S2(dppe)2] · 2 DMF ( 1 ), [Cu3NbS4(PPh3)4] ( 2 ), [Au3NbSe4(PPh3)4] · Et2O ( 3 ), [Cu4NbS4Cl(PCy3)4] ( 4 ), [Cu4NbS4Cl(PtBu3)4] · 0,5 DMF ( 5 ), [Cu4NbSe4(NCS)(PtBu3)4] · DMF ( 6 ), [Cu4NbS4(NCS)(dppm)4] · Et2O ( 7 ), [Cu5NbSe4Cl2‐ (dppm)4] · 3 DMF ( 8 ), [Cu2Nb2S4Cl2(PMe3)6] · DMF ( 9 ), [Au2Nb2Se4Cl2(PMe3)6] · DMF ( 10 ), (NEt4)2[Cu3Nb2S4(NCS)5(dppm)2(dmf)] · 4 DMF ( 11 ), [Cu3NbS3Br(PPh3)3(dmf)3]Br · [CuBr(PPh3)3] · PPh3 · OPPh3 · 3 DMF ( 12 ), [Cu3NbS3Cl2(PPh3)3(dmf)2] · 1.5 DMF ( 13 ), (NEt4)[Cu3NbSe3Cl3(dmf)3] ( 14 ), [Cu6Nb2Se6O2(PMe3)6] ( 15 ). The structures of these compounds were obtained by X‐ray single crystal structure analysis.  相似文献   

8.
A series of mononuclear binary and ternary Cu(I) complexes with formato, formamide, methylphenol, and methanethiolato ligands were optimized at DFT-B3LYP/6-31G** (BS1) and DFT-B3LYP/6-311++G** (BS2) levels of theory. The solvent effect was taken into account via PCM method (BS1W and BS2W, respectively). The coordination arrangement for [CuI(SCH3/S(H)CH3)(OOCH)]?/0 and [CuI(SCH3/S(H)CH3)(O(H)(C6H4)CH3)]0/+ was pseudo-linear and for [CuI(SCH3/S(H)CH3)(OOCH)(OC(H)NH2)]?/0 was pseudo-trigonal. The [CuI(S-S(H)CH3/CuI(S-SCH3)]+/0 link even to amide carbonyl and to general O(H)R residues (R=C6H5CH3). [CuI(SCH3)2(O(H)(C6H4)CH3)]? went towards dissociation of the O(H)(C6H4)CH3 ligand, whereas [CuI(S(H)CH3)2(O(H)(C6H4)CH3)]+ converged nicely, maintaining the hydroxy function linked to the metal. The trends of total electronic energies seemed to be significant, suggesting that linear CuIS2 coordination is more suitable than CuIS, CuIS3 and CuIS4 arrangements. The formation energies of [CuI(S(H)CH3/SCH3)(OOCH)]0/?1 were higher than those of [CuI(S(H)CH3/SCH3)2]+/? on starting from [CuI(S(H)CH3/CuI(SCH3)]+/0 by ca. 11–9 kcal mol?1 (BS2W). The structural arrangements, bond distances, and angles as well as computed spectroscopic parameters resulted in good agreement with experimental data for corresponding synthetic complexes and with metal site regions of several copper(I)-proteins. These data help in interpreting structural data of complex biological systems and in constructing reliable force fields for molecular mechanics computations.  相似文献   

9.
Reactions of [Ru{C=C(H)-1,4-C6H4C≡CH}(PPh3)2Cp]BF4 ([ 1 a ]BF4) with hydrohalic acids, HX, results in the formation of [Ru{C≡C-1,4-C6H4-C(X)=CH2}(PPh3)2Cp] [X=Cl ( 2 a-Cl ), Br ( 2 a-Br )], arising from facile Markovnikov addition of halide anions to the putative quinoidal cumulene cation [Ru(=C=C=C6H4=C=CH2)(PPh3)2Cp]+. Similarly, [M{C=C(H)-1,4-C6H4-C≡CH}(LL)Cp ]BF4 [M(LL)Cp’=Ru(PPh3)2Cp ([ 1 a ]BF4); Ru(dppe)Cp* ([ 1 b ]BF4); Fe(dppe)Cp ([ 1 c ]BF4); Fe(dppe)Cp* ([ 1 d ]BF4)] react with H+/H2O to give the acyl-functionalised phenylacetylide complexes [M{C≡C-1,4-C6H4-C(=O)CH3}(LL)Cp’] ( 3 a – d ) after workup. The Markovnikov addition of the nucleophile to the remote alkyne in the cations [ 1 a–d ]+ is difficult to rationalise from the vinylidene form of the precursor and is much more satisfactorily explained from initial isomerisation to the quinoidal cumulene complexes [M(=C=C=C6H4=C=CH2)(LL)Cp’]+ prior to attack at the more exposed, remote quaternary carbon. Thus, whilst representative acetylide complexes [Ru(C≡C-1,4-C6H4-C≡CH)(PPh3)2Cp] ( 4 a ) and [Ru(C≡C-1,4-C6H4-C≡CH)(dppe)Cp*] ( 4 b ) reacted with the relatively small electrophiles [CN]+ and [C7H7]+ at the β-carbon to give the expected vinylidene complexes, the bulky trityl ([CPh3]+) electrophile reacted with [M(C≡C-1,4-C6H4-C≡CH)(LL)Cp’] [M(LL)Cp’=Ru(PPh3)2Cp ( 4 a ); Ru(dppe)Cp* ( 4 b ); Fe(dppe)Cp ( 4 c ); Fe(dppe)Cp* ( 4 d )] at the more exposed remote end of the carbon-rich ligand to give the putative quinoidal cumulene complexes [M{C=C=C6H4=C=C(H)CPh3}(LL)Cp’]+, which were isolated as the water adducts [M{C≡C-1,4-C6H4-C(=O)CH2CPh3}(LL)Cp’] ( 6 a–d ). Evincing the scope of the formation of such extended cumulenes from ethynyl-substituted arylvinylene precursors, the rather reactive half-sandwich (5-ethynyl-2-thienyl)vinylidene complexes [M{C=C(H)-2,5-cC4H2S-C≡CH}(LL)Cp’]BF4 ([ 7 a – d ]BF4 add water readily to give [M{C≡C-2,5-cC4H2S-C(=O)CH3}(LL)Cp’] ( 8 a – d )].  相似文献   

10.
The title clusters [(PPh3)(p-BrC6H4CO2)2RuB10H8] (1) and [(PPh3)2Ru(PPh3)(p-BrC6H4CO2)RuB10H9] (2) have been prepared and characterized by elemental analysis, FT-IR, ^1H, ^13C NMR spectra and single-crystal X-ray diffraction analysis. The clusters crystallize in monoclinic system, space group C2/c, with a =2.569(4) nm, b= 1.546(2) nm, c= 1.927(3) nm ,8=95.11(2)°, Z=8, V=7.622(21) nm^3, Dc=1.533 Mg/m^3, F(000)=3472, S= 1.009, R= 0.0418, wR=0.0775 and triclinic system, space group P-l, with a=1.3142(3) nm, b= 1.3761(3) nm, c=1.8503(4) nm, a =90.445(4)°,β=105.950(4)°, γ108.980(4)°, Z=2, V=3.0251(12) nm^3, Dc = 1.434 Mg/m^3, F(000)= 1316, S=1.007, R=0.0464, wR=0.1175, respectively for 1 and 2. In the structures, both of the dusters are based on a closo-type C2v 1: 2 : 4 : 2 : 2 RUB10 stack with the metal occupying the unique six-connected apical position. In cluster 1, the metal center has three exo-polyhedral ligands: one triphenylphosphine and two dative oxygen atoms of p-bromobenzoates. The other oxygen atoms of two p-bromobenzoate are additionally bonded to B(2) and B(3) atoms respectively, resulting in two exo-cyclic five-membered Ru-O-C-O-B rings and engendering a symmetrical conformation. The cluster 2 is a bimetallic species in which the second ruthenium is bound to the {RUB10} center via one Ru-Ru bond and two {RuHμB} bridges resulting in one closo distorted exo-polyhedral Ru(1)-Ru(2)-B(3)-B(6) tetrahedron.  相似文献   

11.
The propulsion of photocatalytic hydrogen (H2) production is limited by the rational design and regulation of catalysts with precise structures and excellent activities. In this work, the [MoOS3]2− unit is introduced into the CuI clusters to form a series of atomically-precise MoVI−CuI bimetallic clusters of [Cu6(MoOS3)2(C6H5(CH2)S)2(P(C6H4R)3)4] ⋅ xCH3CN (R=H, CH3, or F), which show high photocatalytic H2 evolution activities and excellent stability. By electron push-pull effects of the surface ligand, highest occupied molecular orbital (HOMO) and lowest unoccupied molecular orbital (LUMO) levels of these MoVI−CuI clusters can be finely tuned, promoting the resultant visible-light-driven H2 evolution performance. Furthermore, MoVI−CuI clusters loaded onto the surface of magnetic Fe3O4 carriers significantly reduced the loss of catalysts in the collection process, efficiently addressing the recycling issues of such small cluster-based catalyst. This work not only highlights a competitively universal approach on the design of high-efficiency cluster photocatalysts for energy conversion, but also makes it feasible to manipulate the catalytic performance of clusters through a rational substituent strategy.  相似文献   

12.
Reactions of [NH4]2[MS4](M = Mo,W), CuX(X = Br, I) and PPh3 in the solid state produced four mixed-metal sulfur containing clusters {Cu3MS3X}(PPh3)3S(M = Mo, W; X = Br, I), two of which (1: M = Mo, X = I; 2: M = W, X = Br) were structurally determined. Crystals of 1 and 2 are triclinic, space group P1 (1: a = 11.895(3), b = 13.107(1), c = 20.473(2)Å, α = 74.95(6), β = 84.87(8), γ = 64.27(7)°, Z=2, V=2776.1 Å3, Rw = 0.064 for 6443 observed reflections. 2: a = 11.876 (1), b = 13.065 (2), c = 20.325(2)Å, α = 74.95(1), β= 85.39(1), γ = 64.09(1)°, Z = 2, V = 2737.3Å3, Rw = 0.055 for ·5303 observed reflections). The results of the structure determination showed that the central units of the two cubane-like cluster compounds are composed of four metal atoms and four non-metal atoms situated at alternate corners. The differences of cubane-like cluster compounds obtained from solid state reactions and from solution reactions are discussed.  相似文献   

13.
The ligand 1,3-bis(diphenylphosphinomethyl)benzene, 1,3-C6H4(CH2PPh2)2 undergoes cyclometalation reactions, thus forming derivatives containing the tridentate moiety 2,6-bis(diphenylphosphinomethyl)phenyl,2,6-C6H3(CH2PPh2)2. Complexes of the type trans-[MBr(C6H3CH2PPh2 2)] with M = NiII, PdII, and PtII could be obtained and their crystal structures were here determined by X-ray diffraction (XRD) methods. The Ni complex belongs to the space group P2 1/c with a = 10.257(2), b = 16.234(5), c = 17.475(4) Å, = 109.34(2), and Z = 4. The Pd complex belongs to the space group P2 1/n with a = 10.325(3), b = 16.279(4), c = 17.303(4) Å = 105.34(3), and Z = 4. The Pt complex belongs to the space group P2 1/n with a = 10.127(2), b = 14.776(2), c = 19.023(3) Å, = 91.01(1), and Z = 4. Different distortions are induced by the rigid tridentate ligand on the square planar coordinations of the three metals. A significant difference between the two M-P bond distances is present in the Pt complex and can also be found in an analogous Pd complex.  相似文献   

14.
The compound(n-Bu_4N)_2[W_2Cu_4S_8(S_2CNC_4H_8)_2]was obtained by the reaction of Bu_4NBr,(NH_4)_2WS_4,NaS_2NCC_4H_8 and CuCl in CH_3CN and CH_3OH.It crystallizes in the monoclinicspace group P2_1/c with unit cell parameters:a=21.875(5),b=16.843(4),c=17.745(5),β=101.69(6)°,V=6402(6)~3,Z=4,D_o=1.718 g·cm~(-3).The final R and R_w values converged to 0.055and 0.060 respectively.The structure consists of two‘butterfly’units[WS_4Cu_2]linked togetherby two weak Cu—S bonds and two bridging S_2CNC_4H_8 ligands.Infrared spectra gave charac-teristic absorptions at 495 cm~(-1) for W=S and 450,435,412 cm~(-1) for W—μ-S.  相似文献   

15.
Heterobimetallic complexes of formula [M{(PPh2)2C2B9H10}(S2C2B10H10)M′(PPh3)] (M=Pd, Pt; M′=Au, Ag, Cu) and [Ni{(PPh2)2C2B9H10}(S2C2B10H10)Au(PPh3)] were obtained from the reaction of [M{(PPh2)2C2B10H10}(S2C2B10H10)] (M=Pd, Pt) with [M′(PPh3)]+ (M′=Au, Ag, Cu) or by one‐pot synthesis from [(SH)2C2B10H10], (PPh2)2C2B10H10, NiCl2 ? 6 H2O, and [Au(PPh3)]+. They display d8–d10 intermetallic interactions and emit red light in the solid state at 77 K. Theoretical studies on [M{(PPh2)2C2B9H10}(S2C2B10H10)Au(PPh3)] (M=Pd, Pt, Ni) attribute the luminescence to ligand (thiolate, L)‐to‐“P2‐M‐S2” (ML′) charge‐transfer (LML′CT) transitions for M=Pt and to metal (M)‐to‐“P2‐M‐S2” (ML′) charge‐transfer (MML′CT) transitions for M=Ni, Pd.  相似文献   

16.
Reactions of Pt(PPh3)4 with the sulfines, XYCSO, (X, Y = aryl, S-aryl, S-alkyl, Cl) yield coordination compounds of the type Pt(PPh3)2(XYCSO). Infrared, 31P and 1H NMR spectra reveal that in all cases the sulfine ligand is coordinated side-on via the CS π-bond (Pt—η2-CS). Reactions of Pt(PPh3)4 with either the E- or Z-isomer of (p-CH3C6H4)(CH3S)CSO yields the corresponding E- or Z-coordination compound, Pt(PPh3)2[E-(p-CH3C6H4)(CH3S)CSO] or Pt(PPh3)2[Z-(p-CH3C6H4)(CH3S)CSO], indicating that the configuration of the sulfine ligand is retained upon coordination to the Pt(PPh3)2 unit. The compounds Pt(PPh3)2(XYCSO), containing reactive CX and/or CY bonds (X, Y = S-aryl, S-alkyl, Cl), undergo a rearrangement in solution to give complexes of the type PtX(PPh3)2(YCSO).  相似文献   

17.
The copper hydride clusters [Cu14H12(phen)6(PPh3)4][X]2 (X=Cl or OTf; OTf=trifluoromethanesulfonate, phen=1,10‐phenanthroline) are obtained in good yields by the reaction of [(Ph3P)CuH]6 with phen, in the presence of a halide or pseudohalide source. The complex [Cu14H12(phen)6(PPh3)4][Cl]2 reacts with CO2 in CH2Cl2, in the presence of excess Ph3P, to form the formate complex [(Ph3P)2Cu(κ2‐O2CH)], along with [(phen)(Ph3P)CuCl].  相似文献   

18.
The reaction of CuBr2 with 1,10‐phen‐H2O (1,10‐phen = 1,10‐phenanthroline) gave two compounds: CuBr2(C12H8N2) and Cu3Br3(C12H8N2)2. Their structures have been characterized by single‐crystal X‐ray diffraction analysis, elemental analyses, thermogravimetric analyses (TGA) and measurement of variable temperature magnetic susceptibility. Crystal data for CuBr2(C12‐H8N2): monoclinic, space group P21/n, a = 0.9977(3) nm, b = 0.65138(14) nm, c = 1.8207(4) nm, β = 91.624(18)°, V = 1.1828(5) nm3, Z = 2. Crystal data for Cu3Br3(C12H8N2)2: monoclinic, space group C2/c, a = 1.00167(11) nm, b = 1.4523(4) nm, c = 1.6295(3) nm, β = 94.386(14)°, V = 2.3635(8) nm3, Z = 3.  相似文献   

19.
We have designed new trithiols Temp(SH)3 and Tefp(SH)3 that can be synthesized conveniently in short steps and are useful for preparation of crystalline [3:1] site-differentiated [4Fe-4S] clusters suitable for X-ray structural analysis. The ethanethiolate clusters (PPh4)2[Fe4S4(SEt)(TempS3)] ( 4a ) and (PPh4)2[Fe4S4(SEt)(TefpS3)] ( 4b ) were prepared as precursors, and the unique iron sites were then selectively substituted. Upon reaction with H2S, (PPh4)2[Fe4S4(SH)(TempS3)] ( 6a ) and (PPh4)2[Fe4S4(SH)(TefpS3)] ( 6b ), which model the [4Fe-4S] cluster in the β subunit of (R)-2-hydroxyisocaproyl-CoA dehydratase, were synthesized. Clusters 6a and 6b were further converted to the sulfido-bridged double cubanes (PPh4)4[{Fe4S4(TempS3)}22-S)] ( 6b ) and (PPh4)4[{Fe4S4(TefpS3)}22-S)] ( 7b ), respectively, via intermolecular condensation with the release of H2S. Conversely, addition of H2S to 7a , 7b afforded the hydrosulfide clusters 6a , 6b . The molecular structures of the clusters reported herein were elucidated by X-ray crystallographic analysis. Their redox properties were investigated by cyclic voltammetry.  相似文献   

20.
Bis(triorganometal) 1,2-dithiolates (R3M)2S2R′ [(HS)2R′ = C7H8S2 for toluene-dithiol-3,4 (H2TDT); M = Sn, Pb; R = Ph; or (HS)2R′ = C10H14S2 for 1,2-dimethyl-4,5-bis(mercaptomethyl)benzene (H2DBB); M = Sn, R = CH3, C6H5; M = Pb, R = C6H5], diorganometal 1,2-dithiolates R2MS2R′ [(HS)2R′ = C6H6S2 for 1,2-dimercaptobenzene (H2DMB); M = Pb, R = CH3, C2H5, C6H5; or (HS)2R′ = H2TDT; M = Sn, R = CH3, C6H5; M = Pb, R = C6H5; or (HS)2R′ = H2DBB; M = Sn, R = CH3, C6H5; M = Pb, R = CH3, C2H2, C6H5; or (HS)2R′ = C8H6N2S2 for 2,3-dimercaptoquinoxaline (H2QDT); M = Pb, R = C6H5] and some lead(IV) and lead(II) dithiolates Pb(S2R′)n [(HS)2R′ = H2DMB, n = 2; (HS)2R′ = H2TDT, n = 2; (HS)2R′ = H2DBB, n = 1 or 2] have been prepared. Vibrational, 1H NMR, and Mössbauer spectroscopic data are consistent with pentacoordination of tin in R2SnTDT and with tetracoordination of tin in R2SnS2R′ and (R3Sn)2S2R′ in the solid state. The soluble compounds are monomeric in solution. Coupling constants for the methyltin compounds indicate tetracoordination in solution.  相似文献   

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