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1.
《中国化学会会志》2017,64(4):369-378
In the present research, the impact of substitution on the dipole moment, electronic structure, and frontier orbital energy in trans ‐(H3P )22‐BH4 )W(≡C‐para ‐C6H4X )(CO ) complexes (X = H, F, SiH3 , CN , NO2 , SiMe3 , CMe3 , NH2 , NMe2 ) was studied with mpw1pw91 quantum chemical computations. The nature of the chemical bond between the trans‐[Cl(η2‐BH4 )(H3P ) 2W ] and [C‐para ‐C6H4X ]+ fragments was demonstrated through energy decomposition analysis (EDA ). The percentage composition in terms of the specified groups of frontier orbitals was examined for these complexes to investigate the feature in metal–ligand bonds. Quantum theory of atoms in molecules (QTAIM ) and natural bond orbital (NBO ) analysis were applied to elucidate these complexes’ metal–ligand bonds.  相似文献   

2.
《中国化学会会志》2017,64(5):522-530
In this study, we report the substituent effect on the structures, frontier orbital analysis, and spectroscopic properties (IR , 13C , 29Si NMR ) in the molybdenum silylidyne complexes CpMo (CO )2(≡Si‐para ‐C6H4X ) (X = H, F, Cl, CN , NO2 , Me, OMe , NH2 , NHMe ) using MPW1PW91 quantum chemical calculations. The calculated structural parameters and spectral parameters are compatible with the experimental values in similar complexes. The nature of the chemical bond between the [Cp(OC ) 2Mo ] and [Si‐para ‐C6H4X ]+ fragments was explored with energy decomposition analysis (EDA ). The percentage composition in terms of the defined groups of frontier orbitals for CpMo (CO )2(≡Si‐para ‐C6H4X ) complexes was investigated to explore the character of the metal–ligand bonds. The linear correlations between the properties and Hammett constants (σ p) were illustrated. Natural bond orbital analysis (NBO ) was used to illustrate the electronic structure of the complexes.  相似文献   

3.
Reaction Behaviour of Copper(I) and Copper(II) Salts Towards P(C6H4CH2NMe2‐2)3 ‐ the Solid‐State Structures of {[P(C6H4CH2NMe2‐2)3]CuOClO3}ClO4, {[P(C6H4CH2NMe2‐2)3]Cu}ClO4, [P(C6H4CH2NMe2‐2)3]CuONO2 and [P(C6H4CH2NMe2‐2)2(C6H4CH2NMe2H+NO3‐2)]CuONO2 The reaction behaviour of P(C6H4CH2NMe2‐2)3 ( 1 ) towards different copper(II) and copper(I) salts of the type CuX2 ( 2a : X = BF4, 2b : X = PF6, 2c : X = ClO4, 2d : X = NO3, 2e : X = Cl, 2f : X = Br, 13 : X = O2CMe) and CuX ( 5a : X = ClO4, 5b : X = NO3, 5c : X = Cl, 5d : X = Br) is discussed. Depending on X, the transition metal complexes [P(C6H4CH2NMe2‐2)3Cu]X2 ( 3a : X = BF4, 3b : X = PF6), {[P(C6H4CH2NMe2‐2)3]CuX}X ( 4 : X = ClO4, 11a : X = Cl, 11b : X = Br, 14 : X = O2CMe), {[P(C6H4CH2NMe2‐2)3]Cu}ClO4 ( 6 ), [P(C6H4CH2NMe2‐2)3]CuX ( 7a : X = Cl, 7b : X = Br, 10 : X = ONO2), [P(C6H4CH2NMe2‐2)2(C6H4CH2NMe2H+NO3‐2)]CuONO2 ( 9 ) and [P(C6H4CH2NMe2‐2)3]CuCl}CuCl2 ( 12 ) are accessible. While in 3a , 3b and 6 the phosphane 1 preferentially acts as tetrapodale ligand, in all other species only the phosphorus atom and two of the three C6H4CH2NMe2 side‐arms are datively‐bound to the appropriate copper ion. In solution a dynamic behaviour of the latter species is observed. Due to the coordination ability of X in 3a , 3b and 6 non‐coordinating anions X are present. However, in 4 one of the two perchlorate ions forms a dative oxygen‐copper bond and the second perchlorate ion acts as counter ion to {[P(C6H4CH2NMe2‐2)3]CuOClO3}+. In 7 , 9 and 10 the fragments X (X = Cl, Br, ONO2) form a σ‐bond with the copper(I) ion. The acetate moiety in 14 acts as chelating ligand as it could be shown by IR‐spectroscopic studies. All newly synthesised cationic and neutral copper(I) and copper(II) complexes are representing stable species. Redox processes are involved in the formation of 9 and 12 by reacting 1 with 2 . The solid‐state structures of 4 , 6 , 9 and 10 are reported. In the latter complexes the copper(II) ( 4 ) or copper(I) ion ( 6 , 9 , 10 ) possesses the coordination number 4. This is achieved by the formation of a phosphorus‐ and two nitrogen‐copper‐ ( 4 , 9 , 10 ) or three ( 6 ) nitrogen‐copper dative bonds and a coordinating ( 4 ) or σ‐binding ( 9 , 10 ) ligand X. In 6 all three nitrogen and the phosphorus atoms are coordinatively bound to copper, while X acts as non‐coordinating counter‐ion. Based on this, the respective copper ion occupies a distorted tetrahedral coordination sphere. While in 4 and 10 a free, neutral Me2NCH2 side‐arm is present, which rapidly exchanges in solution with the coordinatively‐bound Me2NCH2 fragments, this unit is protonated in 10 . NO3 acts as counter ion to the CH2NMe2H+ moiety. In all structural characterized complexes 6‐membered boat‐like CuPNC3 cycles are present.  相似文献   

4.
Complexes of Titanium — Synthesis, Structure, and Fluxional Behaviour of CpTi{η6‐C5H4=C(p‐Tol)2}Cl (Cp′ = Cp*, Cp) The reaction of Cp′TiCl3 (C′ = Cp* or Cp) with magnesium and 6, 6‐di‐para‐tolylpentafulvene generates good yields of pentafulvene complexes Cp*Ti{η6‐C5H4=C(p‐Tol)2}Cl ( 4 ) and CpTi{η6‐C5H4=C(p‐Tol)2}Cl ( 5 ), respectively. The crystal and molecular structure of 4 have been determined from X‐ray data and exhibits compared to known η6‐pentafulvene complexes an unusual large Ti—C(p‐Tol)2 (Fv)‐distance (2.535(5)Å) evoked by the bulky substituents at the exocyclic carbon. Dynamic 1H‐NMR and spin saturation transfer experiments point out a rotation of the fulvene ligand around the Ti—Ct2 axis (Ct2 = centroid of the fulvene ring carbon atoms) with an activation barrier ΔGC = 60.6 ± 0.5 kJ mol−1 (TC = 314 ± 2 K). For 5 this barrier is significantly larger. Analogous dynamic behaviour is well known for diene complexes, but to our knowledge, it is here first‐time described for a pentafulvene complex.  相似文献   

5.
The complex [Rh(η3‐benzyl)(dippe)] ( 1 ; dippe=bis(diisopropylphosphino)ethane=(ethane‐1,2‐diyl)bis[diisopropylphosphine]) reacted cleanly with Mes*PH2 ( 2 ; Mes*=2,4,6‐tBu3C6H2) to provide a new Rh species [Rh(H)(dippe)(L)] ( 3 ), L being the 2,3‐dihydro‐3,3‐dimethyl‐1H‐phosphindole ligand 4 (=tBu2C6H2(CMe2CH2PH)) (Scheme 1). Complex 3 was converted to the corresponding chloride [Rh(Cl)(dippe)(L)] ( 6 ) when treated with CH2Cl2, whereas the dimeric species [Rh2{μtBu2C6H2(CMe2CH2P)}(μ‐H)(dippe)2] ( 7 ) was formed upon thermolysis in toluene (Scheme 2). The structures of 6 and 7 ⋅C7H8 were determined by X‐ray crystallography. Complexes 1 and 3 served as catalyst precursors for the dehydrogenative coupling of C−H and P−H bonds in the conversion of 2 to 4 (Scheme 3). Deuteration studies with Mes*PD2 exposed a complex series of bond‐activation pathways that appear to involve C−H activation of the dippe ligand by the Rh‐atom (Schemes 4 and 5)  相似文献   

6.
Crystallization experiments with the dinuclear chelate ring complex di‐μ‐chlorido‐bis[(η2‐2‐allyl‐4‐methoxy‐5‐{[(propan‐2‐yloxy)carbonyl]methoxy}phenyl‐κC1)platinum(II)], [Pt2(C15H19O4)2Cl2], containing a derivative of the natural compound eugenol as ligand, have been performed. Using five different sets of crystallization conditions resulted in four different complexes which can be further used as starting compounds for the synthesis of Pt complexes with promising anticancer activities. In the case of vapour diffusion with the binary chloroform–diethyl ether or methylene chloride–diethyl ether systems, no change of the molecular structure was observed. Using evaporation from acetonitrile (at room temperature), dimethylformamide (DMF, at 313 K) or dimethyl sulfoxide (DMSO, at 313 K), however, resulted in the displacement of a chloride ligand by the solvent, giving, respectively, the mononuclear complexes (acetonitrile‐κN)(η2‐2‐allyl‐4‐methoxy‐5‐{[(propan‐2‐yloxy)carbonyl]methoxy}phenyl‐κC1)chloridoplatinum(II) monohydrate, [Pt(C15H19O4)Cl(CH3CN)]·H2O, (η2‐2‐allyl‐4‐methoxy‐5‐{[(propan‐2‐yloxy)carbonyl]methoxy}phenyl‐κC1)chlorido(dimethylformamide‐κO)platinum(II), [Pt(C15H19O4)Cl(C2H7NO)], and (η2‐2‐allyl‐4‐methoxy‐5‐{[(propan‐2‐yloxy)carbonyl]methoxy}phenyl‐κC1)chlorido(dimethyl sulfoxide‐κS)platinum(II), determined as the analogue {η2‐2‐allyl‐4‐methoxy‐5‐[(ethoxycarbonyl)methoxy]phenyl‐κC1}chlorido(dimethyl sulfoxide‐κS)platinum(II), [Pt(C14H17O4)Cl(C2H6OS)]. The crystal structures confirm that acetonitrile interacts with the PtII atom via its N atom, while for DMSO, the S atom is the coordinating atom. For the replacement, the longest of the two Pt—Cl bonds is cleaved, leading to a cis position of the solvent ligand with respect to the allyl group. The crystal packing of the complexes is characterized by dimer formation via C—H…O and C—H…π interactions, but no π–π interactions are observed despite the presence of the aromatic ring.  相似文献   

7.
Three novel zinc complexes [Zn(dbsf)(H2O)2] ( 1 ), [Zn(dbsf)(2,2′‐bpy)(H2O)]·(i‐C3H7OH) ( 2 ) and [Zn(dbsf)(DMF)] ( 3 ) (H2dbsf = 4,4′‐dicarboxybiphenyl sulfone, 2,2′‐bpy = 2,2′‐bipyridine, i‐C3H7OH = iso‐propanol, DMF = N,N‐dimethylformamide) were first obtained and characterized by single crystal X‐ray crystallography. Although the results show that all the complexes 1–3 have one‐dimensional chains formed via coordination bonds, unique three‐dimensional supramolecular structures are formed due to different coordination modes and configuration of the dbsf2? ligand, hydrogen bonds and π–π interactions. Iso‐propanol molecules are in open channels of 2 while larger empty channels are formed in 3 . As compared with emission band of the free H2dbsf ligand, emission peaks of the complexes 1–3 are red‐shifted, and they show blue emission, which originates from enlarging conjugation upon coordination. Copyright © 2006 John Wiley & Sons, Ltd.  相似文献   

8.
The title compound, [Co(C19H15N3O5S)(C12H8N2)]·5H2O, has a moderately distorted octahedral coordination environment composed of two N atoms of a 1,10‐phenanthroline ligand and one N and three O atoms of an N‐{[4‐(1,3‐benzothiazol‐2‐yl)anilino]carbonylmethyl}iminodiacetate (ZL‐52−) ligand. The ring systems of the phenanthroline and ZL‐52− ligands are coplanar and the complexes pack in layers parallel to the ab plane with the rings of adjacent complexes facing one another. The layers stack along the c axis and are linked by hydrogen bonds involving the five water solvent molecules in the asymmetric unit and O atoms of the acetate groups of the ZL‐52− ligand. This is believed to be the first crystal structure of a complex of a 2‐(4‐aminophenyl)benzothiazole ligand.  相似文献   

9.
The structure of the title compound, [PtCl2(C5H5N)(C2H6S)], consists of discrete mol­ecules in which the Pt‐atom coordination is slightly distorted square planar. The Cl atoms are trans to each other, with a Cl—Pt—Cl angle of 176.60 (7)°. The pyridine ligand is rotated 64.5 (2)° from the Pt square plane and one of the Pt—Cl bonds essentially bisects the C—S—C angle of the di­methyl sulfide ligand. In the crystal structure, there are extensive weak C—H⋯Cl interactions, the shortest of which connects mol­ecules into centrosymmetric dimers. A comparison of the structural trans influence on Pt—S and Pt—­N distances for PtS(CH3)2 and Pt(pyridine) fragments, respectively, in square‐planar PtII complexes is presented.  相似文献   

10.
The coordination chemistry of platinum(II) with a series of thiosemicarbazones {R(H)C2=N3‐N2(H)‐C1(=S)‐N1H2, R = 2‐hydroxyphenyl, H2stsc; pyrrole, H2ptsc; phenyl, Hbtsc} is described. Reactions of trans‐PtCl2(PPh3)2 precursor with H2stsc (or H2ptsc) in 1 : 1 molar ratio in the presence of Et3N base yielded complexes, [Pt(η3‐ O, N3, S‐stsc)(PPh3)] ( 1 ) and [Pt(η3‐ N4, N3, S‐ptsc)(PPh3)] ( 2 ), respectively. Further, trans‐PtCl2(PPh3)2 and Hbtsc in 1 : 2 (M : L) molar ratio yielded a different compound, [Pt(η2‐ N3, S‐btsc)(η1‐S‐btsc)(PPh3)] ( 3 ). Complex 1 involved deprotonation of hydrazinic (‐N2H‐) and hydroxyl (‐OH) groups, and stsc2? is coordinating via O, N3, S donor atoms, while complex 2 involved deprotonation of hydrazinic (‐N2H‐) and ‐N4H groups and ptsc2? is probably coordinating via N4, N3, S donor atoms. Reaction of PdCl2(PPh3)2 with Hbtsc‐Me {C6H5(CH3)C2=N3‐N2(H)‐C1(=S)‐N1H2} yielded a cyclometallated complex [Pd(η3‐C, N3, S‐btsc‐Me)(PPh3)] ( 4 ). These complexes have been characterized with the help of analytical data, spectroscopic techniques {IR, NMR (1H, 31P), U.V} and single crystal X‐ray crystallography ( 1 , 3 and 4 ). The effects of substituents at C2 carbon of thiosemicarbazones on their dentacy and cyclometallation are emphasized.  相似文献   

11.
In the title complex, {[Cu(C6H5O3)Cl(H2O)]·H2O}n, the CuII atom has a deformed square‐pyramidal coordination geometry formed by two O atoms of the maltolate ligand, two bridging Cl atoms and the coordinated water O atom. The Cu atoms are bridged by Cl atoms to form a polymeric chain. The deprotonated hydroxyl and ketone O atoms of the maltolate ligand form a five‐membered chelate ring with the Cu atom. Stacking interactions and hydrogen bonds exist in the crystal.  相似文献   

12.
Compounds including the free or coordinated gas‐phase cations [Ag(η2‐C2H4)n]+ (n=1–3) were stabilized with very weakly coordinating anions [A]? (A=Al{OC(CH3)(CF3)2}4, n=1 ( 1 ); Al{OC(H)(CF3)2}4, n=2 ( 3 ); Al{OC(CF3)3}4, n=3 ( 5 ); {(F3C)3CO}3Al‐F‐Al{OC(CF3)3}3, n=3 ( 6 )). They were prepared by reaction of the respective silver(I) salts with stoichiometric amounts of ethene in CH2Cl2 solution. As a reference we also prepared the isobutene complex [(Me2C?CH2)Ag(Al{OC(CH3)(CF3)2}4)] ( 2 ). The compounds were characterized by multinuclear solution‐NMR, solid‐state MAS‐NMR, IR and Raman spectroscopy as well as by their single crystal X‐ray structures. MAS‐NMR spectroscopy shows that the [Ag(η2‐C2H4)3]+ cation in its [Al{OC(CF3)3}4]? salt exhibits time‐averaged D3h‐symmetry and freely rotates around its principal z‐axis in the solid state. All routine X‐ray structures (2θmax.<55°) converged within the 3σ limit at C?C double bond lengths that were shorter or similar to that of free ethene. In contrast, the respective Raman active C?C stretching modes indicated red‐shifts of 38 to 45 cm?1, suggesting a slight C?C bond elongation. This mismatch is owed to residual librational motion at 100 K, the temperature of the data collection, as well as the lack of high angular data owing to the anisotropic electron distribution in the ethene molecule. Therefore, a method for the extraction of the C?C distance in [M(C2H4)] complexes from experimental Raman data was developed and meaningful C?C distances were obtained. These spectroscopic C?C distances compare well to newly collected X‐ray data obtained at high resolution (2θmax.=100°) and low temperature (100 K). To complement the experimental data as well as to obtain further insight into bond formation, the complexes with up to three ligands were studied theoretically. The calculations were performed with DFT (BP86/TZVPP, PBE0/TZVPP), MP2/TZVPP and partly CCSD(T)/AUG‐cc‐pVTZ methods. In most cases several isomers were considered. Additionally, [M(C2H4)3] (M=Cu+, Ag+, Au+, Ni0, Pd0, Pt0, Na+) were investigated with AIM theory to substantiate the preference for a planar conformation and to estimate the importance of σ donation and π back donation. Comparing the group 10 and 11 analogues, we find that the lack of π back bonding in the group 11 cations is almost compensated by increased σ donation.  相似文献   

13.
The resonance character of Cu/Ag/Au bonding is investigated in B???M?X (M=Cu, Ag, Au; X=F, Cl, Br, CH3, CF3; B=CO, H2O, H2S, C2H2, C2H4) complexes. The natural bond orbital/natural resonance theory results strongly support the general resonance‐type three‐center/four‐electron (3c/4e) picture of Cu/Ag/Au bonding, B:M?X?B+?M:X?, which mainly arises from hyperconjugation interactions. On the basis of such resonance‐type bonding mechanisms, the ligand effects in the more strongly bound OC???M?X series are analyzed, and distinct competition between CO and the axial ligand X is observed. This competitive bonding picture directly explains why CO in OC???Au?CF3 can be readily replaced by a number of other ligands. Additionally, conservation of the bond order indicates that the idealized relationship bB???M+bMX=1 should be suitably generalized for intermolecular bonding, especially if there is additional partial multiple bonding at one end of the 3c/4e hyperbonded triad.  相似文献   

14.
Both coordination and hydrogen bonds contribute to networking in the supramolecular title compound, [Co(C6H6­NO3S)(C12H8N2)(H2O)3]Cl, which contains a discrete [Co(C6H6NO3S)(C12H8N2)(H2O)3]+ complex cation, formed by one 4‐amino­benzene­sulfonate ligand, one 1,10‐phenanthroline ligand and three coordinated water mol­ecules, together with one uncoordinated chloride anion. These discrete cations and chloride anions are connected by hydrogen‐bonding interactions into a two‐dimensional supramolecular motif. Further hydrogen‐bonding interactions consolidate the structural architecture and extend the two‐dimensional supramol­ecular structure into a three‐dimensional network.  相似文献   

15.
Tri(1‐cyclohepta‐2, 4, 6‐trienyl)phosphane, P(C7H7)3 ( 1 ) ([P] when coordinated to a metal) stabilizes platinum(II) ( 2 ) and palladium(II) dihalides ( 3 ) as [P]MX2 with X = Cl ( a ), Br ( b ) and I ( c ). The phosphane coordinates to the metal as a chelate ligand via both phosphorus and the central η2‐C=C bond of one of the cyclohepta‐2, 4, 6‐trienyl rings. The complexes were prepared by various routes, mainly by the reaction of (cod)MCl2 (cod = cycloocta‐1, 5‐diene) with 1 to give the chlorides 2a and 3a , which then could be converted into the bromides 2b , 3b or the iodides 2c , 3c by reaction with NaBr or NaI, respectively. The molecular structure of 2c was determined by X‐ray analysis. Treatment of 2a and 3a with sodium or potassium salts of several pseudohalides afforded the complexes [P]MX2 2d (NCO/NCO), 2e1 (NCS/SCN), 2e1' (SCN/NCS), 2f2 (SeCN/SeCN), 3f1 (NCSe/SeCN), 2g and 3g (X = N3). Attempts failed to synthesize the cyanides 2h and 3h by the same route. By using an excess of trimethylsilyl cyanide in the reaction with 2a in THF solution, the complex trans‐{[(C7H7)3P]2Pt(CN)2} ( 4h ) was obtained instead of 2h . The analogous complexes trans‐{[(C7H7)3P]2MX2} with M = Pt ( 4 ) and Pd ( 5 ) for X = Cl ( a ), Br ( b ), I ( c ) could be prepared from the reaction of the corresponding tetrahalogenometallates and 1 (in the case of 5c from PdI2 and 1 ). In contrast to 4h , the complexes 4a‐c and 5a‐c were found to be labile in solution with respect to partial loss of the phosphane 1 and rearrangement into 2a‐c and 3a‐c , respectively. All compounds were characterized by IR spectroscopy and by multinuclear magnetic resonance spectroscopy (1H, 13C, 31P, 77Se and 195Pt NMR). The ligand [P] in 2 and 3 is fluxional with regard to coordination of the C7H7 rings to the metal.  相似文献   

16.
The title compound, [Hg(C4H4N2S)(C4H3N2S)]2[HgBr4], con­sists of [Hg(pymt)(pymtH)]+ complex cations (pymtH is pyrimidine‐2‐thione) lying across twofold rotation axes in space group Fddd, with linearly coordinated mercury at an Hg—S distance of 2.357 (3) Å, and [HgBr4]2− anions lying at sites of 222 symmetry. The Hg atom is additionally coordinated by two N and two Br atoms, forming a 2+4 effective coordination sphere. The protonated ligand is connected via N—H⋯N hydrogen bonds to the neighbouring unprotonated ligand, thus forming infinite chains of cations.  相似文献   

17.
In the title compound, [CuCl(C7H7O3S)(C12H8N2)(H2O)], the central Cu atom is coordinated by a water mol­ecule, a chloride ion, an O‐monodentate p‐toluene­sulfonate anion and an N,N′‐bidentate 1,10‐phenanthroline ligand. The copper environment is best described as a slightly distorted square pyramid, with bond distances Cu—Cl 2.2282 (9) Å, Cu—OW 1.984 (3) Å, and Cu—N 2.006 (3) and 2.028 (3) Å; the apical Cu—O distance is 2.281 (2) Å. In the supramolecular structure, π–π‐stacking stabilization is observed, and classical and non‐classical hydrogen bonds also play an important role.  相似文献   

18.
The reaction of the betain‐like compound O2C2(PPh3)2 ( 1 ) with [(cod)PtX2] in THF solution gives the salt‐like compounds (HC{PPh3}2)[(η3‐C8H11)PtX2] ( 3 , X = I; 4 , X = Cl) in about quantitative yields. The new η3‐bonded C8H11 ligand is the result of a proton transfer from the coordinated cod ligand to 1 with subsequent release of CO2. The X‐ray analysis of 3 shows the presence of two isomers in a 60:40 ratio, which differ in the bonding of the C8H11 ligand. 3 crystallizes in the triclinic space group with the unit cell dimensions a = 1091.7(1), b = 1141.5(1), c = 1649.4(2) pm; α = 80.34(1)°, β = 83.62(1)°, γ = 89.03(1)°, V = 2013.7(4)·106 pm3, Z = 2.  相似文献   

19.
A number of alkyltin(IV) paratoluenesulfonates, RnSn(OSO2C6H4CH3‐4)4?n (n = 2, 3; R = C2H5, n‐C3H7, n‐C4H9), have been prepared and IR spectra and solution NMR (1H, 13C, 119Sn) are reported for these compounds, including (n‐C4H9)2Sn(OSO2X)2 (X = CH3 and CF3), the NMR spectra of which have not been reported previously. From the chemical shift δ(119Sn) and the coupling constants 1J(13C, 119Sn) and 2J(1H, 119Sn), the coordination of the tin atom and the geometry of its coordination sphere in solutions of these compounds is suggested. IR spectra of the compounds are very similar to that observed for the paratoluenesulfonate anion in its sodium salt. The studies indicate that diorganotin(IV) paratoluenesulfonates, and the previously reported compounds (n‐C4H9)2Sn(OSO2X)2 (X = CH3 and CF3), contain bridging SO3X groups that yield polymeric structures with hexacoordination around tin and contain non‐linear C? Sn? C bonds. In triorganotin(IV) sulfonates, pentacoordination for tin with a planar SnC3 skeleton and bidentate bridging paratoluenesulfonate anionic groups are suggested by IR and NMR spectral studies. The X‐ray structure shows [(n‐C4H9)2Sn(OSO2C6H4CH3‐4)2·2H2O] to be monomeric containing six‐coordinate tin and crystallizes from methanol–chloroform in monoclinic space group C2/c. The Sn? O (paratoluenesulfonate) bond distance (2.26(2) Å) is indicative of a relatively high degree of ionic character in the metal–anion bonds. Copyright © 2003 John Wiley & Sons, Ltd.  相似文献   

20.
2‐Aminopyrimidine (L1) and 2‐amino‐4,6‐dimethylpyrimidine (L2) have been used to create the two novel title complexes, [Ag2(NCS)2(C4H5N3)]n, (I), and [Ag(NCS)(C6H9N3)]n, (II). The structures of complexes (I) and (II) are mainly directed by the steric properties of the ligands. In (I), the L1 ligand is bisected by a twofold rotation axis running through the amine N atom and opposite C atoms of the pyrimidine ring. The thiocyanate anion adopts the rare μ3‐κ3S coordination mode to link three tetrahedrally coordinated AgI ions into a two‐dimensional honeycomb‐like 63 net. The L1 ligands further extend the two‐dimensional sheet to form a three‐dimensional framework by bridging AgI ions in adjacent layers. In (II), with three formula units in the asymmetric unit, the L2 ligand bonds to a single AgI ion in a monodentate fashion, while the thiocyanate anions adopt a μ3‐κ1N2S coordination mode to link the AgL2 subunits to form two‐dimensional sheets. These layers are linked by N—H...N hydrogen bonds between the noncoordinated amino H atoms and both thiocyanate and pyrimidine N atoms.  相似文献   

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