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1.
The organometallic tin(IV) complexes [SnPh2(SRF)2] SRF = SC6F4-4-H (1), SC6F5 (2), were synthesized and their reactivity with [MCl2(PPh3)2] M = Ni, Pd and Pt explored. Thus, transmetallation products were obtained affording polymeric [Ni(SRF)(μ-SRF)]n, monomeric cis-[Pt(PPh3)2(SC6F4-4-H)2] (3) and cis-[Pt(PPh3)2(SC6F5)2] (4) and dimeric species [Pd(PPh3)(SC6F4-4-H)(μ-SC6F4-4-H)]2 (5) and [Pd(PPh3)(SC6F5)(μ-SC6F5)]2 (6) for Ni, Pt and Pd, respectively. The crystal structures of complexes 1, 2, 3, 4 and 6 were determined.  相似文献   

2.
Reactions of labile [MCl3(PPh3)2(NCMe)] (M = Tc, Re) precursors with 1H-benzoimidazole-2-thiol (H2L1), 5-methyl-1H-benzoimidazole-2-thiol (H2L2) and 1H-imidazole-2-thiol (H2L3), in the presence of PPh3 and [AsPh4]Cl gave a new series of trigonal bipyramidal M(III) complexes [AsPh4]{[M(PPh3)Cl(H2L1-3)3]Cl3} (M = Re, 1-3; M = Tc, 4-6). The molecular structures of 1 and 3 were determined by X-ray diffraction. When the reactions were carried out with benzothiazole-2-thiol (HL4) and benzoxazole-2-thiol (HL5), neutral paramagnetic monosubstituted M(III) complexes [M(PPh3)2Cl2(L4,5)] (M = Re, 8, 9; M = Tc, 10, 11) were obtained. In these compounds, the central metal ions adopt an octahedral coordination geometry as authenticated by single crystal X-ray diffraction analysis of 8 and 11. Rhenium and technetium complexes 1, 4 and rhenium chelate compounds 8, 9 have been also synthesized by reduction of [MO4] with PPh3 and HCl in the presence of the appropriate ligand. All the complexes were characterized by elemental analyses, FTIR and NMR spectroscopy.  相似文献   

3.
Palladium(II) complexes with triphenylphosphine (PPh3) and thioamides of the general formulae, [Pd(L)2(PPh3)2]Cl2 and [Pd(L)2(PPh3)2] have been prepared and characterized by elemental analysis, IR and NMR (1H, 13C and 31P) methods, and two of them (trans-[Pd(PPh3)2(Dmtu)2]Cl2·(H2O)(CH3OH)0.5 (1) and trans-[Pd(PPh3)2(Mpy)2] (2)) by X-ray crystallography; where L = thiourea (Tu), methylthiourea (Metu), N,N′-dimethylthiourea (Dmtu), tetramethylthiourea (Tmtu), 2-mercaptopyridine (Mpy), 2-mercaptopyrimidine (Mpm) and thionicotinamide (Tna). The spectral data of the complexes are consistent with the sulfur coordination of thioamides to palladium(II). The crystal structures of the complexes show that (1) has ionic character consisting of [Pd(PPh3)2(Dmtu)2]+2 cations and uncoordinated Cl ions, while (2) is a neutral complex with Mpy behaving as anionic thiolate ligand. The coordination environment around palladium in (2) is nearly regular square-planar, while in (1) the trans angles show significant distortions from 180°. The complexes were screened for antibacterial effects, brine shrimps lethality bioassay and antitumor activity. These complexes showed significant activities in most of the cases against the tested bacteria as compared to that of a standard drug. Their antitumor activity against prostate cancer cells (PC3) is comparable with doxorubicin, together with no cytotoxic effects in brine shrimps lethality bioassay study.  相似文献   

4.
Palladium(II) and platinum(II) complexes with N-alkylpyridylpyrazole-derived ligands, 2-(1-ethyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L1) and 2-(1-octyl-5-phenyl-1H-pyrazol-3-yl)pyridine (L2), cis-[MCl2(L)] (M = Pd(II), Pt(II)), have been synthesised. Treatment of [PdCl2(L)] (L = L1, L2) with excess of ligand (L1, L2), pyridine (py) or triphenylphosphine (PPh3) in the presence of AgBF4 and NaBPh4 produced the following complexes: [Pd(L)2](BPh4)2, [Pd(L)(py)2](BPh4)2 and [Pd(L)(PPh3)2](BPh4)2. All complexes have been characterised by elemental analyses, conductivity, IR and NMR spectroscopies. The crystal structures of cis-[PdCl2(L2)] (2) and cis-[PtCl2(L1)] (3) were determined by a single crystal X-ray diffraction method. In both complexes, the metal atom is coordinated by one pyrazole nitrogen, one pyridine nitrogen and two chlorine atoms in a distorted square-planar geometry. In complex 3, π-π stacking between pairs of molecules is observed.  相似文献   

5.
The reactions of the Fe(II) and Ru(II) halogenide complexes [Fe(PPh3)2Br2], [Fe(NCCH3)2Br2], [Ru(PPh3)3Cl2], and [Ru(dmso)4Cl2] with GaCp and AlCp, respectively, are investigated. The reactions of [FeBr2L2] with ECp exclusively proceed via Cp transfer, leading to [FeCp(GaCp)(GaBr2)(PPh3)] (1) (L = PPh3, E = Ga), [FeCp(GaCp)2 (GaBr2)] (2) (L = NCCH3, E = Ga) and [FeCp(μ3-H)(κ2-(C6H4)PPh2)(AlCp)(AlBr2)] (3) (L = PPh3, E = Al), the latter of which is formed via orthometallation of one PPh3 ligand. The reaction of [Ru(dmso)4Cl2] leads to the homoleptic complex [Ru(GaCp)6Cl2] (4) in high yields, while [Ru(PPh3)3Cl2] gives 4 in rather low yields. The reason for this difference in reactivity is investigated and it is shown that Cp transfer and orthometallation are the limiting side reactions of the reaction of [Ru(PPh3)3Cl2] with GaCp. All compounds were characterized by NMR spectroscopy, and single crystal X-ray diffraction studies were performed for 1, 3, and 4.  相似文献   

6.
Two new pyrazole-derived ligands, 1-ethyl-3,5-bis(2-pyridyl)pyrazole (L1) and 1-octyl-3,5-bis(2-pyridyl)pyrazole (L2), both containing alkyl groups at position 1 were prepared by reaction between 3,5-bis(2-pyridyl) pyrazole and the appropriate bromoalkane in toluene using sodium ethoxide as base.The reaction between L1, L2 and [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) resulted in the formation complexes of formula [MCl2(L)] (M = Pd(II), L = L1 (1); M = Pd(II), L = L2 (2); M = Pt(II), L = L1 (3); M = Pt(II), L = L2 (4)). These complexes were characterised by elemental analyses, conductivity measurements, infrared, 1H, 13C{1H} NMR and HMQC spectroscopies. The X-ray structure of the complex [PtCl2(L2)] (4) was determined. In this complex, Npyridine and Npyrazole donor atoms coordinate the ligand to the metal, which complete its coordination with two chloro ligands in a cis disposition.  相似文献   

7.
Six copper(I) complexes {[Cu2(L1)(PPh3)2I2] · 2CH2Cl2}n (1), {[Cu2(L2)(PPh3)2]BF4}n (2), [Cu2(L3)(PPh3)4I2] · 2CH2Cl2 (3), [Cu2(L4)(PPh3)4I2] (4), [Cu2(L5)(PPh3)2I2] (5) and [Cu2(L6)(PPh3)2I2] (6) have been prepared by reactions of bis(schiff base) ligands: pyridine-4-carbaldehyde azine (L1), 1,2-bis(4′-pyridylmethyleneamino)ethane (L2), pyridine-3-carbaldehyde azine (L3), 1,2-bis(3′-pyridylmethyleneamino)ethane (L4), pyridine-2-carbaldehyde azine (L5), 1,2-bis(2′-pyridylmethyleneamino)ethane (L6) with PPh3 and copper(I) salt, respectively. Ligand L1 or L2 links (PPh3)2Cu2(μ-I)2 units to form an infinite coordination polymer chain. Ligand 3 or 4 acts as a monodentate ligand to coordinate two copper(I) atoms yielding a dimer. Ligand 5 or 6 chelates two copper(I) atoms using pyridyl nitrogen and imine nitrogen to form a dimer. Complexes 1-4 exhibit photoluminescence in the solid state at room temperature. The emission has been attributed to be intraligand π-π* transition mixed with MLCT characters.  相似文献   

8.
The linkage isomers, (OC)5M[κ1-PPh2 CH2CH(PPh2)2] 1 and (OC)5M[κ1-PPh2 CH(PPh2)CH2PPh2] 2 (M = Cr, Mo and W) exist in equilibrium at room temperature. Equilibrium constants for 1Cr ? 2Cr, 1Mo ? 2Mo and 1W ? 2W at 25 °C in CDCl3 are 2.61, 5.0 and 4.74, respectively. Enthalpy favors the forward reaction (ΔH = −13.5, −12 and −12.2 kJ mol−1, respectively) while entropy favors the reverse reaction (ΔS = −37.6, −28 and −28.2 J K−1 mol−1, respectively). Isomerization is much faster than chelation with 1Mo ? 2Mo ? 1W ? 2W > 1Cr ? 2Cr. Enthalpies of activation for 1Cr ? 2Cr and 1W ? 2W are 119.0 and 92.6 kJ mol−1, respectively, and entropies of activation are 1.4 and −28.2 J K−1 mol−1, respectively. Isomerization is 104 times faster for these complexes than for (OC)5M[κ1-PPh2CH2CH2P(p-tolyl)2]. A novel mechanism is proposed to account for the rate differences. The X-ray crystal structure of 2W shows that the phosphorus atom of the short phosphine arm lies very close to a carbon atom of the W(CO)4 equatorial plane (3.40 Å) which could allow “through-space” coupling, accounting in part for the observation of long-range JPC and JPW coupling. The X-ray structure of (OC)5W[κ1-PPh2 C(CH2)PPh2] 5W has been determined for comparison to 2W.  相似文献   

9.
Two isomeric dibenzo-O2S2 macrocycles L1 and L2 have been synthesised and their coordination chemistry towards palladium(II) has been investigated. Two-step approaches via reactions of 1:1-type complexes, [cis-Cl2LPd] (1a: L = L1, 1b: L = L2), with different O2S2 macrocycle systems (L1 and L2) have led to the isolation of the following bis(O2S2 macrocycle) palladium(II) complexes in the solid state: [Pd(L1)2](ClO4)2 (2a) and a mixture of [Pd(L1)2](ClO4)2 (2a) + [Pd(L2)2](ClO4)2 (2b).  相似文献   

10.
Reaction of the ligands 3-phenyl-5-(2-pyridyl)pyrazole (HL1), 3,5-bis(2-pyridyl)pyrazole (HL2), 3-methyl-5-(2-pyridyl)pyrazole (HL3) and 3-methyl-5-phenylpyrazole (HL4) with [MCl2(CH3CN)2] (M = Pd(II), Pt(II)) or [PdCl2(cod)] gives complexes with stoichiometry [PdCl2(HL)2] (HL = HL1, HL2, HL3), [Pt(L)2] (L = L1, L2, L3) and [MCl2(HL4)2] (M = Pd(II), Pt(II)). The new complexes were characterised by elemental analyses, conductivity measurements, infrared and 1H NMR spectroscopies. The crystal and molecular structure of [PdCl2(HL1)] was resolved by X-ray diffraction, and consists of monomeric cis-[PdCl2(HL1)] molecules. The palladium centre has a typical square planar geometry, with a slight tetrahedral distortion. The tetra-coordinated metal atom is bonded to one pyridine nitrogen, one pyrazolic nitrogen and two chloro ligands in a cis disposition. The ligand HL1 is not completely planar.  相似文献   

11.
The reaction between Pd(dba)2 and phosphino-amide ligands yielded the unexpected Pd(II) homoleptic complexes [Pd(o-Ph2PC6H4CO-NR)2] [R = iPr (1), Ph (2), 4-MeC6H4 (3), 4-FC6H4 (4)], in which an κ2-P,N coordination mode for diphenylphosphine-benzamidate ligands is observed. In order to induce amide protonation in the ligands and subsequent κ2-P,O coordination, compounds (1-4) were treated with HClO4(aq) to give cationic complexes [Pd(o-Ph2PC6H4CO-NHR)2][ClO4]2 (5-8). These complexes and the analogous with iminophosphine ligands [Pd(o-Ph2PC6H4CHN-R)2] [ClO4]2 [R = iPr (9), Ph (10)] can be alternatively obtained when [PdCl2(PhCN)2] is treated with AgClO4 in the presence of the corresponding ligand. The reaction of Pd(dba)2 with iminophosphines has also been explored, yielding in this case the Pd(0) derivatives [Pd(o-Ph2PC6H4CHN-R)2] [R = iPr (11), Ph (12)]. X-ray structures of (3), (4), (5), (8) and (9) have been established, allowing an interesting comparative structural discussion.  相似文献   

12.
The first [Pd(Ln)2(ox)] xH2O oxalato(ox) complexes involving 2-chloro-N6-(benzyl)-9-isopropyladenine (L1; complex 1), 2-chloro-N6-(4-methoxybenzyl)-9-isopropyladenine (L2; 2), 2-chloro-N6-(2,3-dimethoxybenzyl)-9-isopropyladenine (L3; 3), 2-chloro-N6-(2,4-dimethoxybenzyl)-9-isopropyladenine (L4; 4), and 2-chloro-N6-(4-methylbenzyl)-9-isopropyladenine (L5; 5) have been synthesized by the reactions of potassium bis(oxalato)palladate(II) dihydrate, [K2Pd(ox)2]·2H2O, with the mentioned organic compounds (H2ox = oxalic acid; x = 0 for 1-3 and 5 or 2 for 4). Elemental analyses (C, H, N), FTIR, Raman and NMR (1H, 13C, 15N) spectroscopies, conductivity measurements and thermal studies (thermogravimetric and differential thermal analyses, TG/DTA) have been used to characterize the prepared complexes. The molecular structures of [Pd(L2)2(ox)] (2) and [Pd(L5)2(ox)]·L5·Me2CO (5·L5·Me2CO) have been determined by a single crystal X-ray analysis. The geometry of these complexes is slightly distorted square-planar with two appropriate Ln (n = 2 or 5) molecules mutually arranged in the head-to-head (2) or head-to-tail (5) orientation. The Ln ligands are coordinated to the central Pd(II) ion via the N7 atoms. The same conclusions regarding the binding properties of L1-L5 ligands can be made based on multinuclear NMR spectra. In vitro cytotoxicity of the complexes 1-5 has been evaluated against human chronic myelogenous leukaemia (K562) and human breast adenocarcinoma (MCF7) cancer cell lines. Significant cytotoxicity has been determined for the complexes 3 (IC50 = 6.2 μM) and 5 (IC50 = 6.8 μM) on the MCF7 cell line, which is even better than that found for the well-known and widely-used platinum-bearing antineoplastic drugs, i.e. oxaliplatin and cisplatin.  相似文献   

13.
Metathesis reaction between equimolar amount of [Et4N][GaCl4] and Na2edt in methanol resulted in the formation of the dichloro complex [Et4N][Ga(edt)Cl2] (1), whereas reaction of [Et4N][GaCl4] with two equivalents of Na2edt in methanol gave the complex [Et4N][Ga(edt)2] (2) which can act as a metalloligand. Treatment of 2 with M(PPh3)2NO3 in DMF/CH2Cl2 afforded the heterobimetallic complexes [Ga(edt)2M-(PPh3)2] (M = Cu 3, Ag 4) in moderate yields. The structures of 1-4 were determined by single-crystal X-ray diffraction analyses. Both [Ga(edt)Cl2] and [Ga(edt)2] anions have a distorted tetrahedral geometry. The former consists of one five-membered ring formed by chelating dithiolate and two terminal chloride atoms while the latter consists of two five-membered rings formed by two the chelating dithiolates. Complexes 3 and 4 consist of metalloligand [Ga(edt)2] anion chelated to [M(PPh3)2]+via the sulfur atoms. Both tetrahedrally coordinated Ga and Cu(Ag) atoms are bridged by two sulfur atoms, forming a planar “GaS2M” (M = Cu, Ag) core. Thermogravimetry analysis revealed that heterobimetallic complexes 3 and 4 decomposed to give the corresponding ternary metal sulfide materials.  相似文献   

14.
A series of osmium(VI) nitrido complexes containing pyridine-carboxylato ligands OsVI(N)(L)2X (L = pyridine-2carboxylate (1), 2-quinaldinate (2) and X = Cl (a), Br (1b and 2c) or CH3O (2b)) and [OsVI(N)(L)X3] (L = pyridine-2,6-dicarboxylate (3) and X = Cl (a) or Br (b)) have been synthesised. Complexes 1 and 2 are electrophilic and react readily with various nucleophiles such as phosphine, sulfide and azide. Reaction of OsVI(N)(L)2X (1 and 2) with triphenylphosphine produces the osmium(IV) phosphiniminato complexes OsVI(NPPh3)(L)2X (4 and 5). The kinetics of nitrogen atom transfer from the complexes OsVI(N)(L)2Br (2c) (L = 2-quinaldinate) with triphenylphosphine have been studied in CH3CN at 25.0 °C by stopped-flow spectrophotometric method. The following rate law is obtained: −d[Os(VI)]/dt = k2[Os(VI)][PPh3]. OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) reacts also with [PPN](N3) to give an osmium(III) dichloro complex, trans-[PPN][OsIII(L)2Cl2] (6). Reaction of OsVI(N)(L)2Cl (L = 2-quinaldinate) (2a) with lithium sulfide produces an osmium(II) thionitrosyl complex OsII(NS)(L)2Cl (7). These complexes have been structurally characterised by X-ray crystallography.  相似文献   

15.
Reaction of [(p-cymene)RuCl2(PPh3)] (1) or [CpMCl2(PPh3)] (Cp = C5Me5) (3a: M = Rh; 4a: M = Ir) with 1-alkynes and PPh3 were carried out in the presence of KPF6, generating the corresponding alkenyl-phosphonio complexes, [(p-cymene)RuCl(PPh3){CHCR(PPh3)}](PF6) (2a: R = Ph; 2b: R = p-tolyl) or [CpMCl(PPh3){CHCPh(PPh3)}](PF6) (5: M = Rh; 6: M = Ir). Similar reactions of complexes [CpRhCl2(L1)] (3a: L1 = PPh3; 3c: L1 = P(OMe)3) with L2 (L2 = PPh3, PMePh2, P(OMe)3) gave [CpRhCl(L1)(L2)](PF6) (7bb: L1 = L2 = PMePh2; 7ca: L1 = P(OMe)3, L2 = PPh3; 7cc: L1 = L2 = P(OMe)3). Alkenyl-phosphonio complex 5 was treated with P(OMe)3 or 2,6-xylyl isocyanide, affording [CpRhCl(L){CHCPh(PPh3)}](PF6) (8a: L = P(OMe)3; 8b: L = 2,6-xylNC). X-ray structural analyses of 2a, 6 and 8a revealed that the phosphonium moiety bonded to the Cβ atom of the alkenyl group are E configuration.  相似文献   

16.
Palladium [PdCl2(L)] complexes with N-alkylpyridylpyrazole derived ligands [2-(5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L1), 2-(1-ethyl-5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L2), 2-(1-octyl-5-trifluoromethyl-1H-pyrazol-3-yl)pyridine (L3), and 2-(3-pyridin-2-yl-5-trifluoromethyl-pyrazol-1-yl)ethanol (L4) were synthesised. The crystal and molecular structures of [PdCl2(L)] (L = L2, L3, L4) were resolved by X-ray diffraction, and consist of monomeric cis-[PdCl2(L)] molecules. The palladium centre has a typical square-planar geometry, with a slight tetrahedral distortion. The tetra-coordinate metal atom is bonded to one pyridinic nitrogen, one pyrazolic nitrogen and two chlorine ligands in cis disposition. Reaction of L (L2, L4) with [Pd(CH3CN)4](BF4)2, in the ratio 1M:2L, gave complexes [Pd(L)]2(BF4)2. Treatment of [PdCl2(L)] (L = L2, L4) with NaBF4 and pyridine (py) and treatment of the same complexes with AgBF4 and triphenylphosphine (PPh3) yielded [Pd(L)(py)2](BF4)2 and [Pd(L)(PPh3)2](BF4)2 complexes, respectively. Finally, reaction of [PdCl2(L4)] with 1 equiv of AgBF4 yields [PdCl(L4)](BF4).  相似文献   

17.
The synthesis of iron(II), cobalt(II) and nickel(II) complexes supported by chelating borate ligands containing one pyrazole and two thioethers, phenyl(pyrazolyl)bis((alkylthio)methyl)borates, [Ph(pz)BtR], is described. The six-coordinate complexes [Ph(pz)Bt]2M, M = Fe (1Fe), Co (1Co) and Ni (1Ni), form exclusively the cis isomers as confirmed by X-ray diffraction analyses. Whereas 1Co and 1Ni are high spin, 1Fe exhibits a room temperature magnetic moment, μeff = 4.1 μB, consistent with spin-crossover behavior. Quantitative analysis of the electronic spectrum of 2Ni leads to a value of Dq = 1086 cm−1, reflective of a ligand field strength somewhat weaker than those imposed by the related tridentate borate ligands Tp or PhTt. Replacement of the methylthioether substituent with the sterically more demanding tert-butylthioether leads to the isolation of [Ph(pz)BttBu]MX, M = Co, X = Cl (2Co); M = Ni, X = Cl (2Ni) or acac (3). The solid state structures of 2Co and 2Ni are chloride-bridged dimers. Additional high-spin cobalt(II) complexes, accessible under distinct preparative conditions, [κ2-Ph(pzH)BttBu] CoCl2·THF (4) and [κ2-Ph(pz)BttBu]2Co (5), have been fully characterized.  相似文献   

18.
Reaction of the potassium salts of N-thiophosphorylated thioureas of common formula RNHC(S)NHP(S)(OiPr)2 [R = pyridin-2-yl (HLa), pyridin-3-yl (HLb), 6-amino-pyridin-2-yl (HLc)] with Cu(PPh3)3I in aqueous EtOH/CH2Cl2 leads to mononuclear [Cu(PPh3)2La,b-S,S′] (1, 2) and [Cu(PPh3)Lc-S,S′] (3) complexes. Using copper(I) iodide instead of Cu(PPh3)3I, polynuclear complexes [Cun(L-S,S′)n] (4-6) were obtained. The structures of these compounds were investigated by IR, 1H, 31P{1H} NMR spectroscopy, ES-MS and elemental analyses. The crystal structures of Cu(PPh3)2Lb (2) and Cu(PPh3)Lc (3) were determined by single-crystal X-ray diffraction.  相似文献   

19.
The synthesis and characterization of several complexes of the composition [{M(terpy)}n(L)](ClO4)m (M = Pt, Pd; L = 1-methylimidazole, 1-methyltetrazole, 1-methyltetrazolate; terpy = 2,2′:6′,2″-terpyridine; n = 1, 2; m = 1, 2, 3) is reported and their applicability in terms of a metal-mediated base pair investigated. Reaction of [M(terpy)(H2O)]2+ with 1-methylimidazole leads to [M(terpy)(1-methylimidazole)](ClO4)2 (1: M = Pt; 2: M = Pd). The analogous reaction of [Pt(terpy)(H2O)]2+ with 1-methyltetrazole leads to the organometallic compound [Pt(terpy)(1-methyltetrazolate)]ClO4 (3) in which the aromatic tetrazole proton has been substituted by the platinum moiety. For both platinum(II) and palladium(II), doubly metalated complexes [{M(terpy)}2(1-methyltetrazolate)](ClO4)3 (4: M = Pt; 5: M = Pd) can also be obtained depending on the reaction conditions. In the latter two compounds, the [M(terpy)]2+ moieties are coordinated via C5 and N4. X-ray crystal structures of 1, 2, and 3 are reported. In addition, DFT calculations have been carried out to determine the energy difference between fully planar [Pd(mterpy)(L)]2+ complexes Ip-IVp (mterpy = 4′-methyl-2,2′:6′,2″-terpyridine; L = 1-methylimidazole-N3 (I), 1-methyl-1,2,4-triazole-N4 (II), 1-methyltetrazole-N3 (III), or 3-methylpyridine-N1 (IV)) and the respective geometry-optimized structures Io-IVo. Whereas this energy difference is larger than 70 kJ mol−1 for compounds I, II, and IV, it amounts to only 0.8 kJ mol−1 for the tetrazole-containing complex III, which is stabilized by two intramolecular C-H?N hydrogen bonds. Of all complexes under investigation, only the terpyridine-metal ion-tetrazole system with N3-coordinated tetrazole appears to be suited for an application in terms of a metal-mediated base pair in a metal-modified oligonucleotide.  相似文献   

20.
Dithioformato [Re{η2-SC(H)S}(NO)P3]BPh4 (1), thioformamido [Re{η2-RNC(H)S}(NO)P3]BPh4 (2) (R = Et, p-tolyl), formamido [Re{η2-PhNC(H)O}(NO)P3]BPh4 (3) and formamidinato [Re{η2-p-tolylNC(H)Np-tolyl}(NO)P3]BPh4 (4) (P = PPh2OEt) complexes were prepared by allowing the hydride ReH2(NO)P3 to react first with triflic acid and then with the appropriate heteroallene CS2, RNCS, PhNCO and p-tolylNCNp-tolyl. Treatment of the ReH2(NO)L(PPh3)2 [L = P(OEt)3, PPh(OEt)2] and ReH2(NO)(PPh3)3 hydrides first with triflic acid and then with isothiocyanate RNCS (R = Et, p-tolyl) gave the [Re{η2-RNC(H)S}(NO){P(OEt)3}(PPh3)2]BPh4 (5, 6) and [Re(η2-RNC(H)S)(NO)(PPh3)3]BPh4 (7) derivatives. Depending on the nature of the phosphite, instead, the reaction of ReH2(NO)L(PPh3)2 and ReH2(NO)(PPh3)3 hydrides first with CF3SO3H and then with isocyanate R1NCO (R1 = Ph, p-tolyl) gave the chelate [Re{η2-R1NC(H)O}(NO){P(OEt)3}(PPh3)2]BPh4 (8) and [Re{η2-R1NC(H)O}(NO)(PPh3)3]BPh4(10) complexes with P(OEt)3 or PPh3, while the η1-coordinate [Re{η1-RNC(H)S}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (9) derivative was obtained with the PPh(OEt)2 phosphite ligand. η1-Coordinate dithioformato [Re{η1-SC(H)S}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (11) and formato [Re{η1-OC(H)O}(NO){PPh(OEt)2}2(PPh3)2]BPh4 (12) complexes, as well as the formamidinato [Re{η2-p-tolylNC(H)Np-tolyl}(NO){P(OEt)3}(PPh3)2]BPh4 (13) derivative were also prepared.  相似文献   

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