2-[5-(3-羟基苯甲酰氨基)-1,3,4-噻二唑]基乙酸乙酯的合成

以丙二酸二乙酯为起始原料,经选择性皂化、酸化、氯化、环合和酰胺化反应合成了2-[5-(3-羟基苯甲酰氨基)-1,3,4-噻二唑]基乙酸乙酯(1),总收率37.2%,其结构经1H NMR,13C NMR,IR和LC-MS(ESI)确证。采用正交实验法[L_9(3~4)]优化了酰胺化反应的条件。结果表明:在最优反应条件{n[2-(5-氨基-[1,3,4]-噻二唑)基乙酸乙酯]∶n(三乙胺)∶n(间羟基苯甲酰氯)=1∶2∶3,于20℃反应8 h}下,1收率75.5%。     

吡啶基咪唑[4,5-f]1,10-菲咯啉合成、表征及与瓜环作用的光谱学考察

设计合成了2个吡啶基菲咯啉衍生物2-(3-吡啶基)咪唑[4,5-f]1,10-菲咯啉(G1)和2-(4-吡啶基)咪唑[4,5-f]1,10-菲咯啉(G2),通过元素分析、质谱和核磁共振氢谱对其结构进行了表征。 利用紫外吸收光谱和荧光光谱法考察了所合成化合物与六元瓜环Q[6]、七元瓜环Q[7]的相互作用,以及体系pH值对主-客体相互作用的影响。 在酸性条件下,Q[6]、Q[7]与Gl以及Q[6]与G2均发生包合形成1∶1的包合物,并有荧光增敏作用;Q[7]与G2作用形成1∶2包合物,且对G2有荧光猝灭作用;Q[6]、Q[7]与G1的包合常数分别为3.00×104和1.86×104 L/mol;Q[6]、Q[7]与G2的包合常数分别为1.64×104和1.01×103 L/mol。 随着体系酸性减弱,瓜环与客体作用减弱,在中性条件下,瓜环未与客体发生包合作用。     

新型苯并咪唑杂多酸盐离子液体的制备及其在催化合成己二酸中的应用

以1-丁基苯并咪唑为起始原料,合成了1-丁基-3-(4-磺酸基丁基)苯并咪唑內盐(1),1-丁基-3-羧甲基苯并咪唑氯盐(2)和1,3-二丁基苯并咪唑溴盐(3);1~3分别与硅钨酸、磷钨酸和磷钼酸在水或者乙醇中反应,合成了5种新型的杂多酸盐离子液体——1-丁基-3-(4-磺酸基丁基)苯并咪唑硅钨酸盐(4a),1-丁基-3-(4-磺酸基丁基)苯并咪唑磷钨酸盐(4b),1-丁基-3-(4-磺酸基丁基)苯并咪唑磷钼酸盐(4c),1-丁基-3-羧甲基苯并咪唑硅钨酸盐(5)和1,3-二丁基苯并咪唑硅钨酸盐(6),其结构经1H NMR,13C NMR和IR表征。并考察了4~6在30%H_2O_2催化氧化环己烯制备己二酸反应中的催化效果。实验结果表明:4b的催化效果最好。在最佳反应条件[环己烯20 mmol,4b 0.16 mmol,n(环己烯)∶n(H2O2)∶n(ILs)=1∶4.4∶0.008]下,己二酸产率71%。     

n + n]-Heterometallomacrocyclic complexes (n > or = 2) prepared from platinum(II)-centred ditopic 2,2':6',2'-terpyridine ligands: dimensional cataloguing by pulsed-field gradient spin-echo NMR spectroscopy

The reaction of 4'-(2-propyn-1-oxy)-2,2':6',2'-terpyridine (HC[triple bond]CCH2Oterpy) with trans-[PtI2(PR3)2] (R = Et, (n)Bu, Ph) results in the regioselective formation of the metalloditopic ligands trans-[Pt(C[triple bond]CCH2Oterpy)2(PR3)2], crystallographic data for which are presented. Each ditopic ligand reacts with FeCl(2).4H(2)O to give heterometallomacrocycles, the smallest of which is a [2 + 2] macrocycle, confirmed structurally for R = Et. The NMR spectroscopic data confirm the formation of symmetrical species, i.e. macrocyclic and not polymeric species. The distribution of products has been investigated using pulsed-field gradient spin-echo (PGSE) diffusion NMR spectroscopy, and indicates that the kinetic products from the reactions of 1, 2 or 3(L) with iron(II) are [Fe(n)L(n)](2n+) with n = 2, 3 or 4. For L = 1 and 2, these mixtures of products convert in solution to the thermodynamically favoured [Fe(2)L(2)](4+).     

Cationic rare-earth metal trimethylsilylmethyl complexes supported by THF and 12-crown-4 ligands: synthesis and structural characterization

To expand the limited range of rare-earth metal cationic alkyl complexes known, a series of mono- and dicationic trimethylsilylmethyl complexes supported by THF and 12-crown-4 ligands with [BPh4]-, [BPh3(CH2SiMe3)]-, [B(C6F5)4]-, [B(C6F5)3(CH2SiMe3)]-, and [Al(CH2SiMe3)4]- anions were prepared from corresponding neutral precursors [Ln(CH2SiMe3)3Ln] (Ln = Sc, Y, Lu; L = THF, n = 2 or 3; L = 12-crown-4, n = 1) as solvent-separated ion pairs. The syntheses of the monocationic derivatives [Ln(CH2SiMe3)2(12-crown-4)n(THF)m]+[A]- are all high yielding and proceed rapidly in THF solution at room temperature. A "one pot" procedure using the neutral species directly for the syntheses of a number of lutetium and yttrium dicationic derivatives [Ln(CH2SiMe3)(12-crown-4)n(THF)m]2+[A]-2 with a variety of different anions, a class of compounds previously limited to just a few examples, is presented. When BPh3 is used to generate the ion triple, the presence of 12-crown-4 is required for complete conversion. Addition of a second equiv of 12-crown-4 and a third equiv of [NMe2PhH]+[B(C6F5)4]- abstracts a third alkyl group from [Ln(CH2SiMe3)(12-crown-4)2(THF)x]2+[B(C6F5)4]-2 (Ln = Y, Lu). X-ray crystallography and variable-temperature (VT) NMR spectroscopy reveal a structural diversity within the known series of neutral 12-crown-4 supported tris(trimethylsilylmethyl) complexes [Ln(CH2SiMe3)3(12-crown-4)] (Ln = Sc, Y, Sm, Gd-Lu) in the solid and solution states. The X-ray structure of [Sc(CH2SiMe3)3(12-crown-4)] exhibits incomplete 12-crown-4 coordination. VT NMR spectroscopy indicates fluxional 12-crown-4 coordination on the NMR time scale. X-ray crystallography of only the second structurally characterized dicationic rare-earth metal alkyl complex [Y(CH2SiMe3)(12-crown-4)(THF)3]2+[BPh4]-2 shows exocyclic 12-crown-4 coordination at the 8-coordinate metal center with well separated counteranions. 11B and 19F NMR spectroscopy of all mono- and dicationic rare-earth metal complexes reported demonstrate that the anions are symmetrical and noncoordinating on the NMR time scale. A series of trends within the 1H and 13C{1H} NMR resonances arising from the Ln-CH2 groups and, in the case of yttrium, the 1JYC coupling constants at the Y-CH2 group and the 89Y chemical shift values are discussed.     

Host–guest complexes of some cucurbit[n]urils with the hydrochloride salts of some imidazole derivatives

Interaction between the normal cucurbit[n]urils (n = 6,7,8; Q[6], Q[7], Q[8]) and a sym-tetramethyl-substituted cucurbit[6]uril derivative (TMeQ[6]) with the hydrochloride salts of some imidazole derivatives N-(4-hydroxylphenyl)imidazole (g1), N-(4-aminophenyl)imidazole (g2), 2-phenylimidazole (g3) in aqueous solution was investigated by using ¹H NMR spectroscopy, electronic absorption spectroscopy and fluorescence spectroscopy, as well as by using a single crystal X-ray diffraction determination. The ¹H NMR spectra analysis established a basic interaction model in which inclusion complexes with a host:guest ratio of 1:1 forms for the Q[6]s and Q[7] cases, while with a host:guest ratio of 1:2 form for the Q[8] cases. It was common that the hosts selectively bound the phenyl moiety of the guests. Absorption spectrophotometric and fluorescence spectroscopic analysis in aqueous solution defined the stability of the host–guest inclusion complexes at pH 5.8 with a host:guest ratio of 1:1 form quantitatively as logK values between 4 and 5 for the smaller hosts Q[6 or 7]s, while with a host:guest ratio of 1:2 form quantitatively as logK values between 11 and 12 for the host Q[8]. Two single crystal X-ray structures of the inclusion complexes TMeQ[6]-g2 · HCl and TMeQ[6]-g3 · HCl showed the phenyl moiety of these two guests inserted into the host cavity, which supported particularly the ¹H NMR spectroscopic study in solution.     

Synthesis, structure and solution NMR properties of (Ph4P)[M(SeC[O]Tol)3], M = Zn, Cd and Hg

Metal selenocarboxylate salts (PPh4)[M(SeC[O]Tol)3] (M = Zn (1), Cd (2) and Hg (3); Tol = C6H4-p-CH3) have been synthesized by reacting Zn(NO3)2 .6H2O, Cd(NO3)2 .4H2O or HgCl2 with (Na+)TolC[O]Se- and PPh4Cl in the ratio of 1 : 4 : 1. The structures of these compounds were determined by single-crystal X-ray diffraction methods. The crystal structures contain discrete cations and anions. In the each anion, the metal center is bound to three TolC[O]Se ligands, primarily through Se, though some long M...O interactions also occur. NMR spectra (113Cd, 199Hg and 77Se, as appropriate) are reported for solutions of [M(SeC[O]Tol)3]-, and of [M(SeC[O]Tol)3](-) - [M(SC[O]Ph)3]- mixtures (M = Zn-Hg), in CH2Cl2 at reduced temperatures. In addition, ESI-MS data have been obtained for [M(SeC[O]Tol)(3)](-) - [M(SC[O]Ph)3]- mixtures (M = Zn-Hg) in acetone and in CH2Cl2. The NMR and ESI-MS studies show that the complexes [M(SeC[O]Tol)n(SC[O]Ph)(3-n)]- (n= 3-0) persist in solution.     

203,205Tl NMR studies of crystallographically characterized thallium alkoxides. X-ray Structures of [TI(OCH2CMe3)]4 and [TI(OAr)]infinity, where OAr = OC6H3(Me)2-2,6 and OC6H3(CHMe2)2-2,6

[Tl(OCH2Me)]4 (1) was reacted with excess HOR to prepare a series of [Tl(OR)]n, where OR = OCHMe2 (2, n = 4), OCMe3 (3, n = 4), OCH2CMe3 (4, n = 4), OC6H3(Me)2-2,6 (5, n = infinity), and OC6H3(CHMe2)2-2,6 (6, n = infinity). Single-crystal X-ray diffraction experiments revealed that in the solid state the alkoxide-ligated compound 4 adopts a cubane structure, whereas the aryloxide derivatives, 5 and 6, formed polymeric chains. Compounds 1-6 were also characterized by 203,205Tl solution and 205Tl solid-state NMR spectroscopy. In solution it was determined that 1-4 retained the [Tl-O]4 cube structure, whereas the polymeric species 5 and 6 appeared to be fluxional. Variations in the solution and solid-state structures for the [Tl(OR)]4 cubes and polymeric [Tl(OAr)]infinity are influenced by the steric hindrance of the ligand. The acidity of the parent alcohol influences the degree of covalency at the Tl metal center, which is reflected in the 203,205Tl chemical shifts for 1-6.     

Mechanochemical preparation of hydrogen-bonded adducts between the diamine 1,4-diazabicyclo[2.2.2]octane and dicarboxylic acids of variable chain length: an X-ray diffraction and solid-state NMR study

Mechanical mixing of solid dicarboxylic acids of variable chain length HOOC(CH(2))(n)COOH (n = 1-7) with solid 1,4-diazabicyclo[2.2.2]octane generates the corresponding salts or co-crystals of the formula [N(CH(2)CH(2))(3)N]-H-[OOC(CH(2))(n)COOH] (n=1-7). Preparation of the same systems from solution has been instrumental for a full characterization of the mechanochemical products by means of single-crystal and powder-diffraction X-ray analyses, as well as by solid-state NMR. The acid-base adducts, whether involving proton transfer from the COOH group to the N-acceptor, that is having ((-))O...H-N((+)) interactions, or the formation of neutral O-H...N hydrogen bonds, show a melting point alternation phenomenon analogous to that shown by the neutral carboxylic acids. The carbon chemical shift tensors of the COOH group obtained from the sideband intensity of low speed spinning NMR spectra provide a reliable criterion for assigning the protonation state of the adducts.     

Lower Rim-Upper Rim Hydrogen-Bonded Adducts of Calix[4]arenes

An upper-rim-substituted calix[4]arene tetracarboxylic acid forms hydrogen-bonded duplexes with lower-rim-substituted tetra(4-pyridyl)- and tetra(3-pyridyl)calix[4]arenes in chloroform. The formation of these adducts was studied by extraction experiments. The association constants determined via (1)H NMR dilution experiments in CDCl(3) are 7.6 x 10(3) and 1.3 x 10(3) M(-1) for the 4-pyridyl and the 3-pyridyl derivative, respectively. IR studies in the solid state and in solution indicate that the interaction is based on hydrogen bonding and that the degree of proton transfer is negligible. VPO measurements support the formation of 1:1 adducts.     

Synthesis,structures, and conformational characteristics of calixarene monoanions and dianions

The synthesis, complete characterization, and solid state structural and solution conformation determination of calix[n]arenes (n = 4, 6, 8) is reported. A complete series of X-ray structures of the alkali metal salts of calix[4]arene (HC4) illustrate the great influence of the alkali metal ion on the solid state structure of calixanions (e.g., the Li salt of monoanionic HC4 is a monomer; the Na salt of monoanionic HC4 forms a dimer; and the K, Rb, and Cs salts exist in polymeric forms). Solution NMR spectra of alkali metal salts of monoanionic calix[4]arenes indicate that they have the cone conformation in solution. Variable-temperature NMR spectra of salts HC4.M (M = Li, Na, K, Rb, Cs) show that they possess similar coalescence temperatures, all higher than that of HC4. Due to steric hindrance from tert-butyl groups in the para position of p-tert-butylcalix[4]arene (Bu(t)C4), the alkali metal salts of monoanionic Bu(t)C4 exist in monomeric or dimeric form in the solid state. Calix[6]arene (HC6) and p-tert-butylcalix[6]arene (Bu(t)C6) were treated with a 2:1 molar ratio of M(2)CO(3) (M = K, Rb, Cs) or a 1:1 molar ratio of MOC(CH(3))(3) (M = Li, Na) to give calix[6]arene monoanions, but calix[6]arenes react in a 1:1 molar ratio with M(2)CO(3) (M = K, Rb, Cs) to afford calix[6]arene dianions. Calix[8]arene (HC8) and p-tert-butylcalix[8]arene (Bu(t)()C8) have similar reactivity. The alkali metal salts of monoanionic calix[6]arenes are more conformationally flexible than the alkali metal salts of dianionic calix[6]arenes, which has been shown by their solution NMR spectra. X-ray crystal structures of HC6.Li and HC6.Cs indicate that the size of the alkali metal has some influence on the conformation of calixanions; for example, HC6.Li has a cone-like conformation, and HC6.Cs has a 1,2,3-alternate conformation. The calix[6]arene dianions show roughly the same structural architecture, and the salts tend to form polymeric chains. For most calixarene salts cation-pi arene interactions were observed.     

六元和七元瓜环与两类端邻苯二甲酰亚胺基紫精轮烷的组装及性质

设计合成了2种不同碳链长度的客体分子1,1'-二甲基邻苯二甲酰亚胺基-4,4'-联吡啶溴化物 (G1)和1,1'-二丁基邻苯二甲酰亚胺基-4,4'-联吡啶溴化物(G2). 利用紫外-可见吸收光谱、 核磁共振波谱和等温滴定量热等方法研究了客体分子G1和G2与六元(Q[6])和七元瓜环(Q[7])的超分子自组装方式. 结果表明, 在加热回流情况下G1与Q[6]利用滑移法能与紫精基团包结形成[2]轮烷结构, 而Q[7]在常温下就能滑过封端基团邻苯二甲酰亚胺与紫精基团包结形成[2]准轮烷结构.     

Synthesis, structural characterization and anion binding studies of palladium macrocycles with hydrogen-bonding ligands

The reactions between [Pd(P-P)(OTf)2] (where P-P=dppp or dppf) and two different bipyridyl ligands (=1,3-bis(4-pyridylmethyl)urea and=1,3- bis(pyridinylmethyl)benzenedicarboxamide) containing hydrogen-bonding units have been studied. The X-ray crystal structures of three of these assemblies have been solved showing them to be the [2+2] metallo-macrocycles [Pd(P-P)(n)]2(OTf)4 [P-P=dppp, n=1, (); P-P=dppp, n=2, (); P-P=dppf, n=1, ()]. To confirm whether the dimeric assembly of one of these species () is retained in solution, several investigations have been carried out. 1H NMR studies in DMSO and high resolution ESI mass spectrometry have shown that is in equilibrium with a larger [3+3] metallo-macrocycle. The equilibrium between these two species can be modified by changing the temperature, concentration or solvent. Also, addition of certain anions (e.g. [H2PO4]-) to the mixture shifts the equilibrium favoring the formation of the [2+2] metallo-macrocycle over the [3+3] (initially present in a larger proportion).     

Dynamic [2]catenanes based on a hydrogen bonding-mediated bis-zinc porphyrin foldamer tweezer: a case study

This paper describes the self-assembly of a new class of three-component dynamic [2]catenanes, which are driven or stabilized by intramolecular hydrogen bonding, coordination, and electrostatic interaction. One of the component molecules 2, consisting of an aromatic oligoamide spacer and two peripheral zinc porphyrin units, was designed to adopt a folded preorganized conformation, which is stabilized by consecutive intramolecular three-centered hydrogen bonds. Component molecule 3 is a linear secondary ammonium bearing two peripheral pyridine units, which was designed to form a 1:1 complex with 24-crown-8 (5). The 1H NMR and UV-vis experiments in CDCl3-CD3CN (4:1 v/v) revealed that, due to the preorganized U-shaped feature, 2 could efficiently bind 3 through the cooperative zinc-pyridine coordination to generate highly stable 1:1 complex 2.3. Adding 5 to the 1:1 solution of 2 and 3 led to the formation of dynamic three-component [2]catenane 2.3.5 as a result of the threading of 3 through 5. 1H NMR studies indicated that in the 1:1:1 solution (3 mM) [2]catenane 2.3.5 was generated in 55% yield at 25 degrees C. The yield was increased with the reduction of the temperature and [2]catenane could be produced quantitatively in a 1:1:2 solution ([2]=3 mM) at -13 degrees C. Replacing 3 with 1,2-bis(4,4'-bipyridinium)ethane (4) in the three-component solution could also give rise to similar dynamic [2]catenane 2.4.5 albeit in slightly lower yield.     

Synthesis and characterization of a metallocycle-based molecular shuttle

Kinetically stable metallocycle-based molecular shuttles of [2]rotaxanes 4a and 4b, along with [3]rotaxanes 5a and 5b, have been prepared using the rhenium(I)-bridged metallocycle 2 and the dumbbell components containing two stations, 3a and 3b. The rotaxanes were self-assembled by hydrogen bonding interactions upon heating a Cl(2)CHCHCl(2) solution containing their components at 70 degrees C. Each rotaxane was isolated in pure form by silica gel chromatography under ordinary laboratory conditions and fully characterized by elemental analysis and various spectroscopic methods. The (1)H NMR signals for the amide NH and the methylene -(CH(2))(4)- of the station were considerably changed when occupied by the metallocycle. In [2]rotaxane 4b, which has a larger naphthyl spacer, the occupied and unoccupied stations gave widely separated signals in the (1)H NMR spectroscopy at room temperature, but averaged signals of two stations were observed in [2]rotaxane 4a, which has a smaller phenyl spacer. This is attributed to the shuttling of the metallocycle between two stations. The coalescence temperature experiment gave a shuttling rate of approximately 670 s(-)(1) at 19 degrees C in CDCl(3), corresponding to an activation free energy (DeltaG()) of 13.3 kcal/mol. With respect to the relative position of the chloride in the rhenium(I) center, two diastereomers are possible in the [2]rotaxane and three diastereomers are possible in the [3]rotaxane. In fact, the rotaxanes exist as diastereomeric mixtures in nearly equal amounts of all possible diastereomers on the basis of the amide NH signals of the station in the (1)H NMR spectroscopy.     

A new twist in anion binding: metallo-helicate hosts for anionic guests

The condensation of 5-chlorocarbonyl-2,2'-bipyridine with a variety of rigid aromatic diamines, L, gave a series of new bisamido-2,2'-bipyridine based ligands (L = 4,4'-methylenediamine, L1; L = 1,1-bis(4-aminophenyl)cyclohexane, L2; L = 1,1-bis(4-amino-3,5-dimethylphenyl)cyclohexane, L3) capable of forming dinuclear triple helicate complexes on coordination to Fe(II). The reaction of various Fe(II) salts with gave: {[Fe2(L1)3](BF4)4, 1; [Fe2(L1)3](ClO4)4, 2; [Fe2(L1)3]Cl4, 3; [Fe2(L1)3](SO4)2, 4; [Fe2(L2)3](BF4)4, 5; [Fe2(L2)3]Cl4, 6; [Fe2(L3)3](BF4)4; 7; [Fe2(L3)3]Cl4, 8; and [Fe2(L3)3](SO4)2, 9, as determined by UV-Vis, IR and 1H NMR spectroscopy, electrospray mass spectrometry (ESMS) and elemental analyses. A UV-Vis complexometric titration experiment between L3 and Fe(BF4)2 established conclusively a [Fe2(L3)3]4+ product species. 1H NMR spectroscopy showed that the complexes exist as both rac-(helical) and meso-(non-helical) isomers in DMSO-d6 solution at 298 K. L1-L3 were designed such that following complexation, six amide hydrogen atoms would line an inter-strand intrahelical cavity of sufficient size to facilitate the binding of guest species within it. Indeed, ESMS studies showed characteristic peaks typical of complex-anion species in solution. Furthermore, 1H NMR titration experiments showed that anions bind within the intrahelical cavity as titration of 1, 5 and 7 with Bu4NCl showed significant downfield shifts in the amide and bipyridyl H6 proton resonances to yield a species of 1 : 2 host to guest stoichiometry. Moreover, addition of Bu4NCl to 1, 5 and 7 shifted the rac-/meso-species distribution from 1 : 2 in favour of the meso- to 100% in favour of the rac-isomer, showing that Cl- ions favour the formation of the triple helicate species in DMSO-d6 solution.     

Synthesis, spectroscopic, and structural studies on transition metal complexes involving homoleptic tripodal selenoether and telluroether coordination

The reaction of [MCl2(NCMe)2] (M = Pd or Pt) with 2 molar equiv of MeC(CH2ER)3 (E = Se, R = Me; E = Te, R = Me or Ph) and 2 molar equiv of TlPF6 affords the bis ligand complexes [M(MeC(CH2ER)3)2][PF6]2. The crystal structure of [Pt(MeC(CH2SeMe)3)2][PF6]2 (C16H36F12P2PtSe6, a = 12.272(10) A, b = 18.563(9) A, c = 15.285(7) A, beta = 113.18(3) degrees, monoclinic, P2(1)/n, Z = 4) confirms distorted square planar Se4 coordination at Pt(II), derived from two bidentate tripod selenoethers with the remaining arm not coordinated and directed away from the metal center. Solution NMR studies indicate that these species are fluxional and that the telluroether complexes are rather unstable in solution. The octahedral bis tripod complexes [Ru(MeC(CH2SMe)3)2][CF3-SO3]2 and [Ru(MeC(CH2TePh)3)2][CF3SO3]2 are obtained from [Ru(dmf)6][CF3SO3]3 and tripod ligand in EtOH solution. The thioether complex (C18H36F6O6RuS8, a = 8.658(3) A, b = 11.533(3) A, c = 8.659(2) A, alpha = 108.33(2) degrees, beta = 91.53(3) degrees, gamma = 106.01(2) degrees, triclinic, P1, Z = 1) is isostructural with its selenoether analogue, involving two facially coordinated trithioether ligands in the syn configuration. NMR spectroscopy confirms that this configuration is retained in solution for all of the bis tripod Ru(II) complexes. These low-spin d6 complexes show unusually high ligand field splittings. The hexaselenoether Rh(III) complex [Rh(MeC(CH2SeMe)3)2][PF6]3 was obtained by treatment of [Rh(H2O)6]3+ with 2 molar equiv of MeC(CH2SeMe)3 in aqueous MeOH in the presence of excess PF6- anion, while the iridium(III) analogue [Ir(MeC(CH2SeMe)3)2][PF6]3 was obtained via the reaction of the Ir(I) precursor [IrCl(C8H14)2]2 with the selenoether tripod in MeOH/aqueous HBF4. NMR studies reveal different invertomers in solution for both the Rh and Ir species. The Cu(I) complexes [Cu(MeC(CH2ER)3)2]PF6 were obtained from [Cu(NCMe)4]PF6 and tripod ligand in CH2Cl2 solution. The corresponding Ag(I) species [Ag(MeC(CH2TeR)3)2]CF3SO3 (R = Me or Ph) were obtained from Ag[CF3SO3] and tripod telluroether. In contrast, a similar reaction with 2 molar equiv of MeC(CH2SeMe)3 afforded only the 1:1 complex [Ag(MeC(CH2SeMe)3)]CF3SO3. The structure of this species (C9H18AgF3O3SSe3, a = 8.120(3) A, b = 15.374(3) A, c = 14.071(2) A, beta = 93.86(2) degrees, monoclinic, P2(1)/n, Z = 4) reveals a distorted trigonal planar geometry at Ag(I) derived from one bidentate selenoether and one monodentate selenoether. These units are then linked to adjacent Ag(I) ions to give a one-dimensional linear chain cation.     

双核Pt(Ⅳ)配合物与Guanosine-5''''-Monophosphate和Glutathione反应的核磁共振光谱研究

合成了一个新型的双核Pt(Ⅳ)配合物{[cis-Pt(NH3)2Cl(OH)2]2(4,4'-methylenedianiline)}(NO3)2(化合物1)及相应的 15N标记化合物{[cis-Pt(15NH3)2Cl(OH)2]2(4,4'-methylenedianiline)}(NO3)2(化合物15N-1).利用1H NMR和ESMS进行了结构表征,化合物15N-1的2D[1H,15N]HSQC NMR发现,该化合物在水溶液中存在同分异构体.2D[1H,15N]HSQC NMR技术跟踪了化合物15N-1与Guanosine-5'-Monophosphate(5'-GMP)和Glutathione(GSH)的反应.结果显示,5'-GMP能在0.5 h内将化合物1还原,而GSH在6 h以后才能够部分的将化合物1还原.化合物1所表现出来的反应性能将有利于提高其治疗效果和降低毒副作用.     

Synthesis, structure, and conformation of aza[1n]metacyclophanes

N-Benzyl substituted aza[1n]metacyclophanes (n = 4, 6, 8, and 10) were prepared in overall 40% isolated yields via Pd-catalyzed aminations. Analyses of the reaction mixtures showed that aza[14]metacyclophane and the related polymer were the primary products ( approximately 60% overall yield); aza[1n]metacyclophanes up to n = 14 and linear oligomers with up to 20 nitrogen atoms (with at least three types of end groups) were detected. Macrocyclic structures for n = 4, 6, and 10 were confirmed by X-ray crystallography. 1,3-Alternate (D(2d)) and 1,3,5-alternate (S(6)) conformations in solution on NMR time scale at low temperatures were found for macrocycles with n = 4 and n = 6, respectively; the barrier for ring inversion was considerably lower for the larger macrocycle.     

About the Keggin isomers: crystal structure of [N(C4H9)4]-gamma-[SiMo2W10O40]n- (n= 4 or 6)

The tetrabutylammonium gamma-dodecatungstosilicate has been crystallized in a 6/1 acetonitrile/water solvent. An X-ray single-crystal analysis was carried out on [N(C4H9)4]4-gamma-[SiW12O40] which crystallizes in the orthorhombic system, space group P2(1)2(1)2(1), with a = 19.0881(3) A, b = 21.4435(3) A, c = 26.0799(1) A, V = 10674.9(2) A3, Z = 4, and rho(calcd) = 2.392 g/cm3. The idealized C2v arrangement of the anion results from the rotation of 60 degrees of two trigonal [W3O13] groups in the Keggin anion. Taking as reference the geometrical characteristics of the Keggin anion, it appears that the bond lengths and bonds angles within the four [W3O13] groups are not significantly modified while the mu-oxo junctions between the two rotated groups and those between the two unrotated groups involve more acute and opened W-O-W angles, respectively. The syntheses and 183W NMR characterizations of the mixed gamma-[SiW10Mo2O40]n- compounds corresponding to the oxidized (Mo(VI); n = 4) and to the two electron-reduced (Mo(V); n = 6) anions are reported. Structural analysis by 183W NMR has proved unambiguously that the C2v structure of the gamma-[SiW10O36]8- subunit is retained in both the compounds. The electronic behavior of the series gamma-[SiW10M2E2O36]6- (M = Mo or W; E = O or S) is examined, compared and related to 183W NMR data.