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1.
New stable azido derivatives of divalent germanium and tin [N3-E14-OCH2CH2NMe2]2 (E14 = Ge (1), Sn (2)) have been synthesized by use of the β-dimethylaminoethoxy ligand that forms the intramolecular E14 ← N coordination bond. Their crystal structures have been determined by X-ray diffraction analysis. Compounds 1 and 2 are centrosymmetric dimers via two intermolecular dative E14 ← O interactions with essentially linear monodentate azide ligands. The dominant canonical form of the E14-azide moieties is E14-N-NN.  相似文献   

2.
New stable heteroleptic germanium(II) and tin(II) compounds [(SiMe3)2N-E14-OCH2CH2NMe2]n (E14 = Ge, n = 1 (1), Sn, n = 2 (2)) have been synthesized and their crystal structures have been determined by X-ray diffraction analysis. While compound 1 is monomer stabilized by intramolecular Ge ← N coordination, compound 2 is associated to dimer via intermolecular dative Sn ← O interactions.  相似文献   

3.
A straightforward method of synthesis of heteroleptic tin (II) alkoxides stabilized by one intramolecular coordination bond was developed. Addition of one equivalent of dimethylamino ethanol to diamide Sn(N(SiMe3)2)2 (5) yields alkoxy-amido derivative Sn(OCH2CH2NMe2)(N(SiMe3)2) (2). Further addition of alcohol leads to corresponding heteroleptic dialkoxides Sn(OCH2CH2NMe2)(OR) (R = Me (6), Et (7), iPr (8), tBu (9), Ph (10)). Catalytic activity of tin (II) compounds in polyurethane formation was tested.  相似文献   

4.
A series of organotin compounds bearing two intramolecular N → Sn coordination bonds RSn(OCH2CH2NMe2)2Cl (R = Me (4), n-Bu (5), Mes (6)) were synthesized in good yields. These compounds as well as 2 (R = Ph) react with PhSnCl3 to give redistribution products RPhSnCl2 and (Me2NCH2CH2O)2SnCl2 (3). The direction of redistribution reactions is reverse to Kocheshkov reaction. DFT calculations have shown that the driving force of the reactions is formation of intramolecular N → Sn coordination bonds in (RO)2SnCl2 (3), the Lewis acid stronger than RSn(OR)2Cl (2, 4-6). The mechanism of the redistribution reaction between 2 and PhSnCl3 consists of two steps: (1) initial exchange of OCH2CH2NMe2 and Cl to give PhSn(OCH2CH2NMe2)Cl2 (7) followed by (2). Ph and OCH2CH2NMe2 exchange.  相似文献   

5.
Two novel Ni(II) complexes {[Ni(en)2(pot)2]0.5CHCl3} (3) {pot = 5-phenyl-1,3,4-oxadiazole-2-thione} (1) and [Ni(en)2](3-pytol)2 (4) {3-pytol = 5-(3-pyridyl)-1,3,4-oxadiazole-2-thiol} (2) have been synthesized using en as coligand. The metal complexes have been characterized by physical and analytical techniques and also by single crystal X-ray studies. The complexes 3 and 4 crystallize in monoclinic system with space group P21/a and P121/c, respectively. The complex 3 has a slightly distorted octahedral geometry with trans (pot) ligands while 4 has a square planar geometry around the centrosymmetric Ni(II) center with ionically linked trans (3-pytol) ligands. The π?π (face to face) interaction plays an important role along with hydrogen bondings to form supramolecular architecture in both complexes.  相似文献   

6.
The preparation, crystal structure and magnetic properties of a new oxalate-containing copper(II) chain of formula {[(CH3)4N]2[Cu(C2O4)2] · H2O}n (1) [(CH3)4N+ = tetramethylammonium cation] are reported. The structure of 1 consists of anionic oxalate-bridged copper(II) chains, tetramethylammoniun cations and crystallization water molecules. Each copper(II) ion in 1 is surrounded by three oxalate ligands, one being bidentate and the other two exhibiting bis-bidenate coordination modes. Although all the tris-chelated copper(II) units from a given chain exhibit the same helicity, adjacent chains have opposite helicities and then an achiral structure results. Variable-temperature magnetic susceptibility measurements of 1 show the occurrence of a weak ferromagnetic interaction through the oxalate bridge [J = +1.14(1) cm−1, the Hamiltonian being defined as H = –JnmSi · Sj]. This value is analyzed and discussed in the light of available magneto-structural data for oxalate-bridged copper(II) complexes with the same out-of-plane exchange pathway.  相似文献   

7.
We report a series (a)-(d) of tandem reactions involving the conversion of: (a) 2CH2(SiMe3)P(Ph)2NSiMe3 [2H(LL′)] (III) into successively [Li(LL′)]2 (1a) and [Pb(LL′)2] (3a); (b) 1a in turn into {[Li(LL″)]2} (2) and [Pb(LL″)2] (4); (c) 1a successively into Sn(LL′)Cl (5) and [Sn(LL″)2] (6); (d) (1b) into (3b). Experimental details for the preparation and characterisation (including elemental analysis and multinuclear NMR spectra in C6D6 and EI mass spectra) of 1a, 2, 3a, 3b, 4, 6, III (a new synthesis) and IV are provided. The X-ray structures of crystalline 4, 6, III and IV are presented; those of 1a, 2 and 3a were previously published.  相似文献   

8.
Novel half-sandwich [C9H5(SiMe3)2]ZrCl3 (3) and sandwich [C9H5(SiMe3)2](C5Me4R)ZrCl2 (R = CH3 (1), CH2CH2NMe2 (2)) complexes were prepared and characterized. The reduction of 2 by Mg in THF lead to (η5-C9H5(SiMe3)2)[η52(C,N)-C5Me4CH2CH2N(Me)CH2]ZrH (7). The structure of 7 was proved by NMR spectroscopy data. Hydrolysis of 2 resulted in the binuclear complex ([C5Me4CH2CH2NMe2]ZrCl2)2O (6). The crystal structures of 1 and 6 were established by X-ray diffraction analysis.  相似文献   

9.
The synthesis and crystal structures of 4,5-bis[(triorganotin)thiolato]-1,3-dithiole-2-thione, (R3Sn)2(dmit), 1, and 4,5-bis[(triorganotin)thiolato]-1,3-dithiole-2-one, (R3Sn)2(dmio), 2, compounds are reported. Compounds, (1 or 2: R = Ph or cyclohexyl, Cy), have been obtained from reaction of R3SnCl with Cs2dmit or Na2dmio. The presence of the two tin centres in (2: R = Ph) is shown in the 13C NMR spectrum by the couplings of both Sn atoms to the dmio olefinic carbons with J values of 29.4 and 24.7 Hz. The δ119 Sn values for (1: R = Ph) and (2: R = Ph) differ by about 30 ppm, values being −20.7 and −50.1 ppm, respectively, in CDCl3 solution. X-ray structure determinations for (1: R = Ph) and (2: R = Ph or Cy) reveal the compounds to have 4-coordinate, distorted tetrahedral tin centres. The dithiolato ligands, dmit and dmio, act as bridging ligands, in contrast to their chelating roles in R2Sn(dmit) and R2Sn(dmio). A further difference between R2Sn(dmit) and R2Sn(dmio), on one hand, and 1 and 2 on the other, is that intermolecular Sn-S and Sn-O interactions are absent in 1 and 2. However, weak intermolecular hydrogen bonding interactions are found in (1: R = Ph) [C-H?π] and in (2: R = Ph) [C-H?π and C-H?O].  相似文献   

10.
Optically active ligands of type Ph2PNHR (R = (R)-CHCH3Ph, (a); (R)-CHCH3Cy, (b); (R)-CHCH3Naph, (c)) and PhP(NHR)2 (R = (R)-CHCH3Ph, (d); (R)-CHCH3Cy, (e)) with a stereogenic carbon atom in the R substituent were synthesized. Reaction with [PdCl2(COD)2] produced [PdCl2P2] (1) (P = PhP(NHCHCH3Ph)2), whose molecular structure determined by X-ray diffraction showed cis disposition for the ligands. All nitrogen atoms of amino groups adopted S configuration. The new ligands reacted with allylic dimeric palladium compound [Pd(η3-2-methylallyl)Cl]2 to gave neutral aminophosphine complexes [Pd(η3-2-methylallyl)ClP] (2a-2e) or cationic aminophosphine complexes [Pd(η3-2-methylallyl)P2]BF4 (3a-3e) in the presence of the stoichiometric amount of AgBF4. Cationic complexes [Pd(η43-2-methylallyl)(NCCH3)P]BF4 (4a-4e) were prepared in solution to be used as precursors in the catalytic hydrovinylation of styrene. 31P NMR spectroscopy showed the existence of an equilibrium between the expected cationic mixed complexes 4, the symmetrical cationic complexes [Pd(η3-2-methylallyl)P2]BF4 (3) and [Pd(η3-2-methylallyl)(NCCH3)2]BF4 (5) coming from the symmetrization reaction. The extension of the process was studied with the aminophosphines (a-e) as well as with nonchiral monodentate phosphines (PCy3 (f), PBn3 (g), PPh3 (h), PMe2Ph (i)) showing a good match between the extension of the symmetrization and the size of the phosphine ligand. We studied the influence of such equilibria in the hydrovinylation of styrene because the behaviour of catalytic precursors can be modified substantially when prepared ‘in situ’. While compounds 3 and bisacetonitrile complex 5 were not active as catalysts, the [Pd(η3-2-methylallyl)(η2-styrene)2]+ species formed in the absence of acetonitrile showed some activity in the formation of codimers and dimers. Hydrovinylation reaction between styrene and ethylene was tested using catalytic precursors solutions of [Pd(η3-2-methylallyl)LP]BF4 ionic species (L = CH3CN or styrene) showing moderate activity and good selectivity. Better activities but lower selectivities were found when L = styrene. Only in the case of the precursor containing Ph2PNHCHCH3Ph (a) ligand was some enantiodiscrimination (10%) found.  相似文献   

11.
Cadmium(II) complexes of 3-hydroxypicolinic acid, namely [CdI(3-OHpic)(3-OHpicH)(H2O)]2 (1), [Cd(3-OHpic)2(H2O)2] (2) and [Cd(3-OHpic)2]n (3) were prepared and characterized by spectroscopic methods (IR, NMR) and their molecular and crystal structures were determined by X-ray crystal structure analysis. Complexes 1 and 2 were prepared in similar reaction conditions using different cadmium(II) salts: cadmium(II) iodide and cadmium(II) acetate dihydrate, respectively, while 3 was prepared by recrystallization of 2 from N,N-dimethylformamide solution. Various coordination modes of 3-OHpicH in 13 were established in the solid state: bidentate N,O-chelated mode in 1 and 2, monodentate mode through the carboxylate O atom from zwitterionic ligand in 1 and bidentate N,O-chelated and bridging mode in 3. In the DMF solution of all prepared complexes, only monodentate mode of 3-OHpicH binding to cadmium(II) through the carboxylate O atom was established by 1H, 13C, 15N and 113Cd NMR spectroscopy.  相似文献   

12.
The novel silicon-, germanium- and tin-containing imido alkyl complexes of tungsten of the type (ArN)2W(CH2EMe3)2 (; E = Si (1), Ge (2), Sn (3)) have been prepared by the reactions of (ArN)2WCl2(dme) (dme = 1,2-dimethoxyethane) with heteroelement-containing alkyllithium or Grignard reagents Me3ECH2Li (E = Si, Ge), Me3ECH2MgCl (E = Ge, Sn). The title compounds were isolated in high yields as crystalline solids and characterized by elemental analysis, IR, 1H, 13C, 29Si and 119Sn NMR spectroscopy and X-ray diffraction studies. The geometry of the W atoms in the compounds can be described as a distorted tetrahedron.  相似文献   

13.
A series of mononuclear ruthenium complexes [RuCl(CO)(PMe3)3(CHCH-C6H4-R-p)] (R = H (2a), CH3 (2b), OCH3 (2c), NO2 (2d), NH2 (2e), NMe2 (2f)) has been prepared. The respective products have been characterized by elemental analyses, NMR spectrometry, and UV-Vis spectrophotometry. The structures of complexes 2c and 2d have been established by X-ray crystallography. Electrochemical studies have revealed that electron-releasing substituents facilitate monometallic ruthenium complex oxidation, and the substituent parameter values (σ) show a strong linear correlation with the anodic half-wave or oxidation peak potentials of the complexes.  相似文献   

14.
The objective of the present work was to synthesize mononuclear ruthenium complex [RuCl2(CO)2{Te(CH2SiMe3)2}2] (1) by the reaction of Te(CH2SiMe3)2 and [RuCl2(CO)3]2. However, the stoichiometric reaction affords a mixture of 1 and [RuCl2(CO){Te(CH2SiMe3)2}3] (2). The X-ray structures show the formation of the cis(Cl), cis(C), trans(Te) isomer of 1 and the cis(Cl), mer(Te) isomer of 2. The 125Te NMR spectra of the complexes are reported. The complex distribution depends on the initial molar ratio of the reactants. With an excess of [RuCl2(CO)3]2 only 1 is formed. In addition to the stoichiometric reaction, a mixture of 1 and 2 is observed even when using an excess of Te(CH2SiMe3)2. Complex 1 is, however, always the main product. In these cases the 125Te NMR spectra of the reaction solution also indicates the presence of unreacted ligand.  相似文献   

15.
A series of novel first-generation silicon-centred tin dendrimers Si(CH2CH2SnR3)4 [R = CH3 (3), iBu (4), CCCH3 (5), C6H4CH3-4 (6), C6H4OCH3-4 (7), (CH2)4OCH2CH2OCH3 (8), CH2SiMe3 (9)] was prepared by the reaction of Si(CH2CH2SnBr3)4 (2) with the appropriate Grignard reagent or LiCH2SiMe3 in tetrahydrofuran. The new compounds were characterized by multinuclear NMR studies (1H, 13C, 119Sn), mass spectrometry (MALDI-TOF, EI) and elemental analyses. The molecular structure of Si[CH2CH2SnBr3(THF)2]2[CH2-CH2SnBr3(THF)]2 (2a) was determined by single-crystal X-ray diffraction.  相似文献   

16.
Reactions of [Pt2(μ-Cl)2(C8H12OMe)2] (1) (C8H12OMe = 8-methoxy-cyclooct-4-ene-1-yl) with various anionic chalcogenolate ligands have been investigated. The reaction of 1 with Pb(Spy)2 (HSpy = pyridine-2-thiol) yielded a binuclear complex [Pt2(Spy)2(C8H12OMe)2] (2). A trinuclear complex [Pt3(Spy)4(C8H12OMe)2] (3) was isolated by a reaction between 2 and [Pt(Spy)2]n. The reaction of 1 with HSpy in the presence of NaOMe generated 2 and its demethylated oxo-bridged tetranuclear complex [Pt4(Spy)4(C8H12-O-C8H12)2] (4). Treatment of 1 with ammonium diisopropyldithiophosphate completely replaced C8H12OMe resulting in [Pt(S2P{OPri}2)2] (5), whereas non-rigid 5-membered chelating ligand, Me2NCH2CH2E, produced mononuclear complexes [Pt(ECH2CH2NMe2)(C8H12OMe)] (E = S (6), Se (7)). These complexes have been characterized by elemental analyses, NMR (1H, 13C{1H}, 195Pt{1H}) and absorption spectroscopy. Molecular structures of 2, 3, 4, 5 and 7 were established by single crystal X-ray diffraction analyses. Thermolysis of 2, 6 and 7 in HDA gave platinum nanoparticles.  相似文献   

17.
The compounds [MoCl(NAr)2R] (R=CH2CMe2Ph (1) or CH2CMe3(2); Ar=2,6-Pri2C6H3) have been prepared from [MoCl2(NAr)2(dme)] (dme=1,2-dimethoxyethane) and one equivalent of the respective Grignard reagent RMgCl in diethyl ether. Similarly, the mixed-imido complex [MoCl2(NAr)(NBut)(dme)] affords [MoCl(NAr)(NBut)(CH2CMe2Ph)] (3). Chloride substitution reactions of 1 with the appropriate lithium reagents afford the compounds [MoCp(NAr)2(CH2CMe2Ph)] (4) (Cp=cyclopentadienyl), [MoInd(NAr)2(CH2CMe2Ph)] (5) (Ind=Indenyl), [Mo(OBut)(NAr)2(CH2CMe 2Ph)] (6), [MoMe(NAr)2(CH2CMe2Ph)] (7), [MoMe(PMe3)(NAr)2(CH2CMe 2Ph)] (8) (formed in the presence of PMe3) and [Mo(NHAr)(NAr)2(CH2CMe2P h)](9). In the latter case, a by-product {[Mo(NAr)2(CH2CMe2Ph) ]2(μ-O)}(10) has also been isolated. The crystal structures of 1, 4, 5 and 10 have been determined. All possess distorted tetrahedral metal centres with cis near-linear arylimido ligands; in each case (except 5, for which the evidence is unclear) there are α-agostic interactions present.  相似文献   

18.
Complexes of three related 1-azapentadienyl ligands [N(SiMe2R1)C(But)(CH)3SiMe2R], abbreviated as L (R = But, R= Me), L′ (R = Me = R1), and L″ (R = But = R1), are described. The crystalline compounds Sn(L)2 (1), Sn(L′)2 (2), [Sn(L′)(μ-Cl)]2 (3) and [Sn(L″)(μ-Cl)]2 (4) were prepared from SnCl2 and 2 K(L), 2 K(L′), K(L′) and K(L″), respectively, in thf. Treatment of the appropriate lithium 1-azapentadienyl with Si(Cl)Me3 yielded the yellow crystalline Me3Si(L) (5) and the volatile liquid Me3Si(L′) (6) and Me3Si(L″) (7), each being an N,N,C-trisilyldieneamine. The red, crystalline Fe(L)2 (8) and Co(L′)2 (9) were obtained from thf solutions of FeCl2 with 2 Li(L)(tmeda) and CoCl2 with 2 K(L′), respectively. Each of 1-9 gave satisfactory C, H, N analyses; 6 and 7 (GC-MS) and 1, 2, 8 and 9 (MS) showed molecular cations and appropriate fragments (also 3 and 4). The 1H, 13C and 119Sn NMR (1-4) and IR spectra support the assignment of 1-4 as containing Sn-N(SiMe2R1)-C(But)(CH)3SiMe2R moieties and 5-7 as N(SiMe3)(SiMe2R1)C(But)(CH)3SiMe2R molecules; for 1-4 this is confirmed by their X-ray structures. The magnetic moments for 8 (5.56 μB) and 9 (2.75 μB) are remarkably close to the appropriate Fe and Co complex [M{η3-N(SiMe3)C(But)C(H)SiMe3}2]; hence it is proposed that 8 and 9 have similar metal-centred, centrosymmetric, distorted octahedral structures.  相似文献   

19.
Hexanuclear oxo titanium(IV) siloxo carboxylate complexes with the general formula [Ti6O6(OSi(CH3)3)6(OOCR)6] (R = But (1), CH2But (2), C(CH3)2Et (3)) were synthesized in quantitative yield, by the reaction of Ti(OSiMe3)4 with the appropriate organic acid. Crystal structure determination revealed that molecules of 13 are composed of [Ti6-(μ3-O)6] cores stabilized by six synsyn carboxylato bridges and six terminal siloxide ligands. Each metal atom is surrounded by six oxo atoms, capping the triangular faces of the distorted octahedron. Spectral characterization (IR, NMR) of 13 revealed a significant non-equivalence of the carboxylate group interactions, resulting from the asymmetry of the Ti-μ-OOC bonds of the synsyn bridges. The thermal stability of the studied compounds was determined from TGA/DTA analysis.  相似文献   

20.
Eight ionic organotin compounds [R2SnCl2(2-quin)](HNEt3)+ have been synthesized by reactions of 2-quinH with R2SnCl2 (R = PhCH21, 2-Cl-C6H4CH22, 4-Cl-C6H4CH23, 2-F-C6H4CH24, 4-F-C6H4CH25, 4-CN-C6H4CH26, Ph 7, 2,4-Cl2-C6H3CH28) in the presence of organic base NEt3, and their structures have been characterized by elemental analysis, IR and multinuclear NMR (1H, 13C, 119Sn) spectroscopies. The structure of [(2,4-Cl2-C6H3CH2)2SnCl2(2-quin)](NEt3)+ (8) has been determined by X-ray diffraction study. Studies show that compound 8 has a monomeric structure with the central tin atom six-coordinate in a distorted octahedral configuration and the nitrogen atoms of the 2-quin ligands are coordinating to the tin atom in all the eight compounds.  相似文献   

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