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1.
尹传奇  吴少文 《化学学报》2003,61(5):666-670
分别研究了在干燥THF及H2O/THF条件下CO2与TpRu(PPh3)(CH3CN)H [Tp=Hydrotris(pyrazolyl)borate]的反应,发现水对CO2插入TpRu(PPh3)(CH3CN)H 的反应具有显著促进作用.原位高压^1H,^31P和^13C核磁共振研究显示,在水存在下 ,CO2插入Ru-H键形成水合甲酸盐配合物TpRu(PPh3)(CH3CN)(η^1-OCHO)·H2O键而 得到增强,进而显著降低CO2插入TpRu(PPh3)(CH3CN)H中Ru-H键的活化能。TpRu (PPh3)(CH3CN)(η^1-OCHO)·H2O很快部分转化为另一甲酸盐配合物TpRu(PPh3)( H2O)(η^1-OCHO),二者最后达成平衡,后者由于甲酸盐配体与水分子配体间形成 分子内氢键而稳定。  相似文献   

2.
研究了溶剂分别为 THF, H2O/THF, CH3CN/THF以及ROH/THF (R=Me, Et, iso-Pr, tert-Bu)条件下TpRuH(PPh3)- (CH3CN) [Tp=hydrotris(pyrazolyl)borate]催化氢化苯乙烯生成乙基苯的反应, 发现向干燥THF体系中添加微量 H2O, CH3CN或ROH对催化反应都具有显著的促进作用. 催化机理研究表明, 小分子添加物首先取代TpRuH(PPh3)(CH3CN)中的PPh3配体形成中间体TpRuH(CH3CN)L (L=H2O, CH3CN或ROH), 降低空间位阻, CH3CN配体随后被苯乙烯取代生成中间体 TpRuH(H2C=CHPh)L; η2-苯乙烯插入Ru—H键后形成的Ru-烷基中间物与H2反应生成η2-H2配合物 TpRu(CH2CH2Ph)(H2)L或TpRu[CH(CH3)Ph](H2)L, 进而发生σ-复分解反应生成乙基苯完成催化循环.  相似文献   

3.
钌配合物催化氢化CO2生成甲酸反应中的醇促进效应   总被引:1,自引:0,他引:1  
在水合钌配合物[TpRu(PPh3)2(H2O)]BF4 [Tp=hydrotris(pyrazolyl) borate]催化氢化二氧化碳生成甲酸的反应中观察到醇对反应的促进作用. 利用原位高压核磁共振跟踪催化反应过程的结果表明, 在甲醇溶液中, [TpRu(PPh3)2(H2O)]BF4在三乙胺和H2作用下转化为TpRu(PPh3)2H. 二氧化碳插入Ru—H生成甲酸根配合物TpRu(PPh3)2(η1-OCHO)•HOCH3, 其中的甲酸根配体与醇分子间形成分子间氢键. 该甲酸根配合物随即转化为另一个甲酸根配合物TpRu(PPh3)(CH3OH)(η1-OCHO)并与之达成平衡, 后者由于存在分子内氢键而稳定. 考虑到这两个甲酸根配合物在催化反应中的稳定性, 它们应该不在主要的催化循环内. 提出了配合物[TpRu(PPh3)2(H2O)]BF4在几种醇溶液中催化氢化二氧化碳生成甲酸的催化循环机理, 催化循环的关键中间体可能是TpRu(PPh3)(ROH)H. 该中间体能同时转移负氢及醇配体中的氢质子到接近的二氧化碳分子上生成甲酸, 并吸收H2生成过渡态TpRu(PPh3)(OR)(H2). 该过渡态经过σ-复分解反应重新生成TpRu(PPh3)(ROH)H完成催化循环.  相似文献   

4.
室温下,在醇水溶液中合成了2个新型配合物,[Zn(phen)3]2·[Zn(C10H16O4)·(H2O)3]·(C10H16O4)2·20H2O(C10H18O4=癸二酸)(1)和[Co(phen)3]2·[Co(H2O)6]·(C10H16O4)3·30H2O(2),并对配合物进行了元素分析分析、红外光谱分析、热重分析以及晶体结构研究.配合物(1)的基本结构单元中含有一个电中性配位单元[Zn(C10H16O4)·(H2O)3]、二个配位阳离子[Zn(phen)3]2+、二个游离的癸二酸根和20个晶格水.Zn原子有两种配位模式,在[Zn(phen)3]2+配位单元中Zn原子与三个邻菲啰啉的六个N原子配位,构成略有畸变的八面体,Zn原子位于八面体的对称中心;在[Zn(C10H16O4)·(H2O)3]配位单元中Zn原子采取五配位的三角双锥构型,两个羧基均采取单齿配位,同一个癸二酸根与相邻的不同Zn原子配位,将相邻的[Zn(C10H16O4)·(H2O)3]配位单元连接起来,自组装得到了无限链状结构.配合物以癸二酸根为模板在ab平面形成了有序水层,该水层由5元,6元水簇,以及其他由羧基参与的各元环组成.与一般常见的6元水簇不同,配合物1中的6元水簇采取了高能量的类似苯环的平面构象.配合物(2)的基本结构单元中含有一个[Co(H2O)6]2+配位阳离子、二个[Co(phen)3]2+配位阳离子、三个游离的癸二酸根和30个晶格水.Co原子也有两种配位模式.在[Co(phen)3]2+配位单元中,Co原子与三个邻菲啰啉的六个N原子配位,构成略有畸变的八面体,Co原子位于八面体的对称中心.在[Co(H2O)6]2+配位单元中Co(II)与6个配位水的氧原子配位,6个配位水中的6个原子和Co(Ⅱ)形成八面体结构.通过水分子之间及水分子和羧基阴离子间的氢键形成了二维有序水层,二维水层中最小的构筑基元为6元环的水,最大的构筑基元为16元环水,每个水环中分别含有6个和16个游离的没有配位的水分子,水分子之间通过很强的氢键作用形成环形的超分子水簇.这些基元片断在二维空间扩展开来,形成二维有序水层.有趣的是,在该水层上通过水分子之间的分子间氢键形成了16元大环水簇,它与两端的六元环共用六条边,每一个16元水环中含有16个游离的没有配位的水分子,水分子之间通过氢键作用形成环形超分子水簇,每个水分子同时作为氢键的给体和受体.[Co(H2O)6]2+和四个羧酸根离子位于十六元环水的中心,与其周围的游离水分子形成了十二个氢键,同时与环外的游离水和羧酸根形成了十个氢键,对大环水聚集体起到稳定作用.  相似文献   

5.
在水和乙醇溶剂中,通过Cu(Ⅱ),Fe(Ⅲ)和Fe(Ⅱ)与2,2'-联咪唑协同作用,构筑了四种新的超分子配合物[Cu(H2biim)(gly)(H2O)]Cl·H2O(1),[Cu(H2biim)(C3H2O4)(H2O)]·1.5H2O(2),[Fe2(μ-O)(H2biim)4(H2O)2](NO3)4·C2H5OH(3)和[Fe(H2biim)3]SO4(4)(H2biim=2,2'-联咪唑;gly-=甘氨酸根;C3H2O24-=丙二酸根).并通过元素分析,红外光谱和X射线单晶衍射对其组成、结构和谱学性质进行研究.H2biim配体,丙二酸根和甘氨酸根三种配体都采用了双齿螯合方式与金属离子配位.配合物1~4中,通过H2biim配体的N-H键与阴离子、水分子和溶剂分子形成多种氢键,如R12(7),R22(9)和R12(4)等,以及H2biim配体之间的π-π堆积,阳离子不对称单元构筑了多维结构的超分子配合物.  相似文献   

6.
富勒烯配合物η2-C60[Ru(NO)(PPh3)]2的合成与表征   总被引:4,自引:0,他引:4  
从1985年Kroto等[1]发现富勒烯至今, 其在化学、材料和物理等领域已有较多的研究[2~8]. 目前有关C60取代的金属小分子配合物(如羰基、亚硝酰基等)的研究方兴未艾. 而以NO为配体的亚硝酰基金属富勒烯配合物仅有数例[2,3], Green等[3]在研究以CO和NO为配体的金属富勒烯系列化合物的合成中, 认为C60不能与Ru(NO)2(PPh3)2发生反应. 本文利用Ru(NO)2(PPh3)2与C60反应首次合成出η2-C60[Ru(NO)(PPh3)]2配合物, 并对其进行了表征.  相似文献   

7.
合成了3个新的氢醌金属配合物:[Co(H2cah)(H2O)2].H2O(1),Ni(H2cah)(H2O)2].H2O(2),[Zn(H2cah)(CH3OH)(H2O)].H2O(3)(H4cah=2-(N,N-二羧甲酸氨甲基)氢醌),通过X-射线单晶衍射,红外光谱,元素分析对它们进行了表征。这些配合物均为单核结构,并且通过分子间的氢键形成了无限的超分子网状结构。电化学研究显示配合物1中的Co2+/Co+对和配合物2中的Ni2+/Ni+对的氧化还原是一个不可逆的过程,但是氢醌到半醌之间的转换是一个准可逆的过程。  相似文献   

8.
The synthesis,the crystal structure and the reaction of the hetero-binuclear complex[MnRe(CO)6(μ-SH)(μ-SC(H)PPr^i3)(PPh3)] are reported.The results of single crystal X-ray structure analysis showed that the fragments Mn(CO)3 and Re(CO)3 were bridged by SH and SC(H)PPr^i3.The title complexes can react with Bu^nLi and RX forming complexes MnRe(CO)6(μ-SR)(μ-SC(H)PPr^i3)(PPh3)](R=Me,CH2CH=CH2,SnBu3^n).  相似文献   

9.
单氢钌配合物与水和2,2,2-三氟乙醇的作用机理   总被引:1,自引:0,他引:1  
利用原位1H和31P NMR对单氢钌配合物TpRu(PPh3)(CH3CN)H [Tp=hydrotris(pyrazolyl)borate]与H2O和酸性HOCH2CF3的反应进行了研究, 结果显示相应的反应产物分别是TpRu(PPh3)(CH3CN)(OH) 和TpRu(PPh3)(CH3CN)(OCH2CF3). 观察到反应过程中Ru-H…HOH和Ru-H…HOCH2CF3分子间的氢键作用. 提出了生成TpRu(PPh3)(CH3CN)(OH)和TpRu(PPh3)(CH3CN)(OCH2CF3)的不同作用机理. 在水存在下, TpRu(PPh3)(CH3CN)H 与H2O反应, 经过中间体TpRu(PPh3)(H2O)H和TpRu(PPh3)(OH)(η2-H2)生成产物TpRu(PPh3)(CH3CN)(OH). 而TpRu(PPh3)(CH3CN)H与酸性HOCH2CF3反应时, 单氢配体被质子化形成中间体[TpRu(PPh3)(CH3CN)- (η2-H2)](OCH2CF3), 进而转变成产物TpRu(PPh3)(CH3CN)(OCH2CF3). TpRu(PPh3)(CH3CN)(OCH2CF3)与H2作用, 经中间体TpRu(PPh3)(HOCH2CF3)H生成TpRu(PPh3)(η2-H2)H.  相似文献   

10.
金琼花  徐立军  孙静静  代永成 《化学学报》2009,67(19):2193-2198
合成了3种新的超分子配合物[Cd(H2biim)(2,2'-bipy)(NO3)2] (1), [Cu(H2biim)(2,2'-bipy)(H2O)](NO3)2 (2)和[Zn(H2biim)(2,2'-bipy)(H2O)](NO3)2 (3) (H2biim=双咪唑; 2,2'-bipy=2,2'-联吡啶), 并通过X射线单晶衍射测定了其结构. 配合物1~3均为单斜晶系, 属于P2(1)/c空间群, 在1中, Cd(II)为六配位, 它与双咪唑的2个氮原子, 联吡啶的2个氮原子和2个硝酸根的2个氧原子配位. 在2和3中, Cu(II)和Zn(II)均为五配位的, 它们与双咪唑的2个氮原子、2,2'-联吡啶的两个氮原子和一个水分子配位. 1~3的对称单元均通过双咪唑、硝酸根和水之间形成的氢键R21(7), R21(4) 和R44(18)构筑了1D链状超分子.  相似文献   

11.
The ruthenium(II) complexes [Ru(R)(κ(2)-S(2)C·IPr)(CO)(PPh(3))(2)](+) (R = CH=CHBu(t), CH=CHC(6)H(4)Me-4, C(C≡CPh)=CHPh) are formed on reaction of IPr·CS(2) with [Ru(R)Cl(CO)(BTD)(PPh(3))(2)] (BTD = 2,1,3-benzothiadiazole) or [Ru(C(C≡CPh)=CHPh)Cl(CO)(PPh(3))(2)] in the presence of ammonium hexafluorophosphate. Similarly, the complexes [Ru(CH=CHC(6)H(4)Me-4)(κ(2)-S(2)C·ICy)(CO)(PPh(3))(2)](+) and [Ru(C(C≡CPh)=CHPh)(κ(2)-S(2)C·ICy)(CO)(PPh(3))(2)](+) are formed in the same manner when ICy·CS(2) is employed. The ligand IMes·CS(2) reacts with [Ru(R)Cl(CO)(BTD)(PPh(3))(2)] to form the compounds [Ru(R)(κ(2)-S(2)C·IMes)(CO)(PPh(3))(2)](+) (R = CH=CHBu(t), CH=CHC(6)H(4)Me-4, C(C≡CPh)=CHPh). Two osmium analogues, [Os(CH=CHC(6)H(4)Me-4)(κ(2)-S(2)C·IMes)(CO)(PPh(3))(2)](+) and [Os(C(C≡CPh)=CHPh)(κ(2)-S(2)C·IMes)(CO)(PPh(3))(2)](+) were also prepared. When the more bulky diisopropylphenyl derivative IDip·CS(2) is used, an unusual product, [Ru(κ(2)-SC(H)S(CH=CHC(6)H(4)Me-4)·IDip)Cl(CO)(PPh(3))(2)](+), with a migrated vinyl group, is obtained. Over extended reaction times, [Ru(CH=CHC(6)H(4)Me-4)Cl(BTD)(CO)(PPh(3))(2)] also reacts with IMes·CS(2) and NH(4)PF(6) to yield the analogous product [Ru{κ(2)-SC(H)S(CH=CHC(6)H(4)Me-4)·IMes}Cl(CO)(PPh(3))(2)](+)via the intermediate [Ru(CH=CHC(6)H(4)Me-4)(κ(2)-S(2)C·IMes)(CO)(PPh(3))(2)](+). Structural studies are reported for [Ru(CH=CHC(6)H(4)Me-4)(κ(2)-S(2)C·IPr)(CO)(PPh(3))(2)]PF(6) and [Ru(C(C≡CPh)=CHPh)(κ(2)-S(2)C·ICy)(CO)(PPh(3))(2)]PF(6).  相似文献   

12.
The octahedral Ru(II) amine complexes [TpRu(L)(L')(NH(2)R)][OTf] (L = L' = PMe(3), P(OMe)(3) or L = CO and L' = PPh(3); R = H or (t)Bu) have been synthesized and characterized. Deprotonation of the amine complexes [TpRu(L)(L')(NH(3))][OTf] or [TpRu(PMe(3))(2)(NH(2)(t)Bu)][OTf] yields the Ru(II) amido complexes TpRu(L)(L')(NH(2)) and TpRu(PMe(3))(2)(NH(t)Bu). Reactions of the parent amido complexes or TpRu(PMe(3))(2)(NH(t)Bu) with phenylacetylene at room temperature result in immediate deprotonation to form ruthenium-amine/phenylacetylide ion pairs, and heating a benzene solution of the [TpRu(PMe(3))(2)(NH(2)(t)Bu)][PhC(2)] ion pair results in the formation of the Ru(II) phenylacetylide complex TpRu(PMe(3))(2)(C[triple bond]CPh) in >90% yield. The observation that [TpRu(PMe(3))(2)(NH(2)(t)Bu)][PhC(2)] converts to the Ru(II) acetylide with good yield while heating the ion pairs [TpRu(L)(L')(NH(3))][PhC(2)] yields multiple products is attributed to reluctant dissociation of ammonia compared with the (t)butylamine ligand (i.e., different rates for acetylide/amine exchange). These results are consistent with ligand exchange reactions of Ru(II) amine complexes [TpRu(PMe(3))(2)(NH(2)R)][OTf] (R = H or (t)Bu) with acetonitrile. The previously reported phenyl amido complexes TpRuL(2)(NHPh) [L = PMe(3) or P(OMe)(3)] react with 10 equiv of phenylacetylene at elevated temperature to produce Ru(II) acetylide complexes TpRuL(2)(C[triple bond]CPh) in quantitative yields. Kinetic studies indicate that the reaction of TpRu(PMe(3))(2)(NHPh) with phenylacetylene occurs via a pathway that involves TpRu(PMe(3))(2)(OTf) or [TpRu(PMe(3))(2)(NH(2)Ph)][OTf] as catalyst. Reactions of 1,4-cyclohexadiene with the Ru(II) amido complexes TpRu(L)(L')(NH(2)) (L = L' = PMe(3) or L = CO and L' = PPh(3)) or TpRu(PMe(3))(2)(NH(t)Bu) at elevated temperatures result in the formation of benzene and Ru hydride complexes. TpRu(PMe(3))(2)(H), [Tp(PMe(3))(2)Ru[double bond]C[double bond]C(H)Ph][OTf], [Tp(PMe(3))(2)Ru=C(CH(2)Ph)[N(H)Ph]][OTf], and [TpRu(PMe(3))(3)][OTf] have been independently prepared and characterized. Results from solid-state X-ray diffraction studies of the complexes [TpRu(CO)(PPh(3))(NH(3))][OTf], [TpRu(PMe(3))(2)(NH(3))][OTf], and TpRu(CO)(PPh(3))(C[triple bond]CPh) are reported.  相似文献   

13.
The transmetallation of the palladacyclopentadiene complex Pd{C(COOMe)C(COOMe)C(COOMe)C(COOMe)}(bipy) with the dicationic Pd(II) complex [Pd(bipy)(CH(3)CN)(2)][BF(4)](2) afforded a terminally σ-palladated diene complex [Pd(2){μ-η(1):η(1)-C(COOMe)C(COOMe)C(COOMe)C(COOMe)}(bipy)(2)(CH(3)CN)(2)][BF(4)](2). It was revealed by X-ray crystallographic analysis that replacement of the acetonitrile ligands in a terminally σ-palladated diene complex with PPh(3) ligands resulted in the conformation change of the σ-palladated diene moiety from skewed s-cis to planar s-trans. Treatment of a bis-triphenylphosphine dipalladium complex [Pd(2)(PPh(3))(2)(CH(3)CN)(4)][PF(6)](2) with dimethoxyacetylene dicarboxylate (DMAD) (1 equiv.) in acetonitrile resulted in the insertion of DMAD to the Pd-Pd bond to afford [Pd(2){μ-η(1):η(1)-C(COOMe)C(COOMe)}(PPh(3))(2)(CH(3)CN)(4)][PF(6)](2). Addition of the second DMAD gave the ylide-type complex [Pd(2){μ-η(2):η(3)-C(COOMe)C(COOMe)C(COOMe)C(COOMe)(PPh(3))}(PPh(3))(2)(CH(3)CN)(3)][PF(6)](2) of which the structure was determined by X-ray crystallographic analysis.  相似文献   

14.
The syntheses of Ir(I) and Ir(III) complexes incorporating the electron-withdrawing pincer ligand (1,3-C(6)H(4)(CH(2)P(CF(3))(2))(2)) ((CF(3))PCPH) with (PPh(3))(3)Ir(CO)H and subsequent chemistry are reported. Under ambient conditions, reaction of 1 equiv. (CF(3))PCPH with (PPh(3))(3)Ir(CO)H gave the mono-bridged complex [Ir(CO)(PPh(3))(2)(H)](2)(μ-(CF(3))PCPH) (1). Reaction of (PPh(3))(3)Ir(CO)H with excess (CF(3))PCPH and MeI gave the doubly-bridged complex [Ir(CO)(PPh(3))(H)](2)(μ-(CF(3))PCPH)(2) (2), whereas the tetrameric oligomer [Ir(CO)(PPh(3))(H)](4)(μ-(CF(3))PCPH)(4) (2-sq) was obtained from a 1:1 ligand:metal mixture in benzene in the presence of excess MeI. At higher temperatures (165 °C) the reaction of (CF(3))PCPH with (PPh(3))(3)Ir(CO)H afforded the 5-coordinate Ir(I) complex ((CF(3))PCP)Ir(CO)(PPh(3)) (3). Complex 3 shows mild catalytic activity for the decarbonylation of 2-naphthaldehyde in refluxing diglyme (162 °C).  相似文献   

15.
Cotton FA  Murillo CA  Wang X  Yu R 《Inorganic chemistry》2004,43(26):8394-8403
Reaction of racemic cis-Rh(2)(C(6)H(4)PPh(2))(2)(OAc)(2)(HOAc)(2) with excess Me(3)OBF(4) in CH(3)CN results in the formation of racemic cis-[Rh(2)(C(6)H(4)PPh(2))(2)(CH(3)CN)(6)](BF(4))(2).0.5H(2)O (1.0.5H(2)O), an ionic dirhodium complex which has two cisoid nonlabile orthometalated phosphine bridging anions and six labile CH(3)CN ligands in equatorial and axial positions. Reactions of 1 with tetraethylammonium salts of the linear dicarboxylates, oxalate, terephthalate, and 4,4'-biphenyl-dicarboxylate, in organic solvents, produced racemic crystals of the triangular compounds [Rh(2)(C(6)H(4)PPh(2))(2)](3)(C(2)O(4))(3)(py)(6).6MeOH.H(2)O (2.6MeOH.H(2)O), [Rh(2)(C(6)H(4)PPh(2))(2)](3)(O(2)CC(6)H(4)CO(2))(3)(DMF)(6).6.5DMF.0.5H(2)O (3.6.5DMF.0.5H(2)O), and [Rh(2)(C(6)H(4)PPh(2))(2)](3)(O(2)CC(6)H(4)C(6)H(4)CO(2))(3)(py)(6).4.5CH(3)OH.0.75H(2)O (4.4.5CH(3)OH.0.75H(2)O), respectively. All compounds are electrochemically active. The relative chiralities of the dirhodium units in each triangle have been established using a combination of data from X-ray crystallography and (31)P NMR spectroscopy.  相似文献   

16.
Adams RD  Kwon OS 《Inorganic chemistry》2003,42(20):6175-6182
Reaction of CpMoMn(CO)(8) with elemental selenium and Me(3)NO in the absence of light yielded the diselenido complex CpMoMn(CO)(5)(mu-Se(2)), 2. Compound 2 contains a bridging diselenido ligand lying perpendicular to the Mo-Mn bond, Mo-Mn = 2.8421(10) A. In the presence of room light, the reaction yielded the tetranuclear metal complex Cp(2)Mo(2)Mn(2)(CO)(7)(mu(3)-Se)(4), 3 (36% yield), and 2 (7% yield). Compound 2 reacted with ethylene to yield the ethanediselenato complex CpMoMn(CO)(5)(mu-SeCH(2)CH(2)Se), 4, by insertion of ethylene into the Se-Se bond. Compound 2 also reacted with (PPh(3))(2)Pt(PhC(2)Ph) and CpCo(CO)(2) to yield the complexes CpMoMnPt(PPh(3))(2)(CO)(5)(mu(3)-Se)(2), 5, and Cp(2)CoMoMn(CO)(5)(mu(3)-Se)(2), 6, respectively, by insertion of the metal groupings CpCo and Pt(PPh(3))(2) into the Se-Se bond of 2. The oxo compound Cp(2)CoMo(O)Mn(CO)(5)(mu(3)-Se)(2), 7, was obtained from 6 by decarbonylation at molybdenum by using Me(3)NO. The molecular structures of the complexes 2-7 were established by single-crystal X-ray diffraction analyses.  相似文献   

17.
Hydration of nitrosylruthenium bis(alkynyl) complex TpRu(CCPh)2(NO) (1) (Tp = BH(pyrazol-1-yl)3) was carried out in the presence of HBF4.Et2O in distilled MeOH and afforded the metallacycle TpRu{CH=C(Ph)C(O)CH(Ph)}(NO) (2) (39%) and the bis(ketonyl) TpRu(CH2C(O)Ph)2(NO) (3) (37%). While double hydration of 1 gave 3, 2 was produced through a combination of insertion and hydration processes. On the other hand, a similar reaction performed in THF instead of MeOH afforded 2 (52%), the acyl-ketonyl complex TpRu(C(O)CH2Ph)(CH2C(O)Ph)(NO) (4) (8.9%), and trace amounts of 3 and TpRu(CCPh)(CH2C(O)Ph)(NO) (5). Moreover, the 1/HBF4.Et2O/H2O reaction system in distilled MeOH at 0 degrees C gave rise to 5 exclusively (79%). Treatment of THF solution of isolated 5 with water in the presence of protic acid furnished 3 and 4, revealing that 5 is the intermediate in their formation.  相似文献   

18.
Metal complexation studies were performed with the ditopic pyrimidine-hydrazone (pym-hyz) strand 6-hydroxymethylpyridine-2-carboxaldehyde (2-methyl-pyrimidine-4,6-diyl)bis(1-methylhydrazone) (1) and Pb(ClO(4))(2)·3H(2)O, Pb(SO(3)CF(3))(2)·H(2)O, Zn(SO(3)CF(3))(2), and Zn(BF(4))(2) to examine the ability of 1 to form various supramolecular architectures. X-ray crystallographic and NMR studies showed that coordination of the Pb(II) salts with 1 on a 2:1 metal/ligand ratio in CH(3)CN and CH(3)NO(2) resulted in the linear complexes [Pb(2)1(ClO(4))(4)] (2), [Pb(2)1(ClO(4))(3)(H(2)O)]ClO(4) (3), and [Pb(2)1(SO(3)CF(3))(3)(H(2)O)]SO(3)CF(3) (4). Two unusually distorted [2 × 2] grid complexes, [Pb1(ClO(4))](4)(ClO(4))(4) (5) and [Pb1(ClO(4))](4)(ClO(4))(4)·4CH(3)NO(2) (6), were formed by reacting Pb(ClO(4))(2)·6H(2)O and 1 on a 1:1 metal/ligand ratio in CH(3)CN and CH(3)NO(2). These grids formed despite coordination of the hydroxymethyl arms due to the large, flexible coordination sphere of the Pb(II) ions. A [2 × 2] grid complex was formed in solution by reacting Pb(SO(3)CF(3))(2)·H(2)O and 1 on a 1:1 metal/ligand ratio in CH(3)CN as shown by (1)H NMR, microanalysis, and ESMS. Reacting the Zn(II) salts with 1 on a 2:1 metal/ligand ratio gave the linear complexes [Zn(2)1(H(2)O)(4)](SO(3)CF(3))(4)·C(2)H(5)O (7) and [Zn(2)1(BF(4))(H(2)O)(2)(CH(3)CN)](BF(4))(3)·H(2)O (8). (1)H NMR studies showed the Zn(II) and Pb(II) ions in these linear complexes were labile undergoing metal ion exchange. All of the complexes exhibited pym-hyz linkages in their cisoid conformation and binding between the hydroxymethyl arms and the metal ions. No complexes were isolated from reacting either of the Zn(II) salts with 1 on a 1:1 metal/ligand ratio, due to the smaller size of the Zn(II) coordination sphere as compared to the much larger Pb(II) ions.  相似文献   

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