开环茂金属成环及氢分子消除反应机理的理论研究

采用密度泛函方法(DFT)在M06-2X/def2-TZVPP//B3LYP/def2-TZVPP+ZPE水平下, 对以开环的(η⁵-C₅H₇)₂Ru为前驱体生成闭环(η⁵-C₅H₅)₂Ru的各种可能的反应路径进行了详细的研究. 最终确定其反应机理为: (η⁵-C₅H₇)₂Ru的一个η⁵-C₅H₇发生端碳成键的成环反应形成(η³-C₅H₇)Ru(η⁵-C₅H₇), 经过两步氢原子迁移到Ru原子上, 之后脱掉一个氢气分子形成(η⁵-C₅H₅)Ru(η⁵-C₅H₇), 而后另一个η⁵-C₅H₇再重复成环并进行两步氢迁移以及氢气分子消除而得到最终的产物(η⁵-C₅H₅)₂Ru.     

含二茂铁基的硫代碳酰腙和缩氨基硫脲的合成

硫代碳酰腙和氨基硫脲衍生物具有一定的生理活性,可作为某些金属离子的特效试剂,本文报道在乙醇-醋酸介质中通过取代氨基硫脲,硫代碳酰腙与不同的二茂铁衍生物缩合,合成了新的缩氨基硫脲和硫代碳酰腙衍生物.     

1/2,5-二取代吲唑-3-甲酰胺衍生物的合成及其抗肿瘤活性

以吲唑-3-羧酸为原料,依次经溴代和酯化反应制得中间体5-溴吲唑-3-羧酸甲酯(2);2经N-烷基化并原位水解生成1/2-取代-5-溴吲唑-3-羧酸(3);3与吡啶酮甲胺类化合物经缩合反应制得酰胺(4);4与芳基频哪醇硼酸酯发生Suzuki偶联反应合成了14个新型二取代吲唑-3-甲酰吡啶酮甲胺衍生物(5a~5n),收率26%~32%,其结构经~1H NMR,~(13)C NMR和HR-MS(ESI-TOF)表征。通过NOE差谱确证了取代基在吲唑氮原子上的取代位置。采用MTT法研究了5a~5n对人B淋巴瘤细胞(Ramos)、人黑色素瘤细胞(CHL-1,WM-266-4)和乳腺癌细胞(BT-474)的体外抗肿瘤活性。结果表明:5a,5b,5m对Ramos细胞、5a,5b,5l对WM-266-4细胞、5a,5b,5d,5e,5h,5j,5m,5n对CHL-1细胞和5a,5b,5d,5h,5m对BT-474细胞具有较好的抑制活性(IC5010.0μmol.L-1)。     

Ammonolysis of mono(pentamethylcyclopentadienyl) titanium(IV) derivatives

Ammonolyses of mono(pentamethylcyclopentadienyl) titanium(IV) derivatives [Ti(eta5-C5Me5)X3] (X = NMe2, Me, Cl) have been carried out in solution to give polynuclear nitrido complexes. Reaction of the tris(dimethylamido) derivative [Ti(eta5-C5Me5)(NMe2)3] with excess of ammonia at 80-100 degrees C gives the cubane complex [[Ti(eta5-C5Me5)]4(mu3-N)4] (1). Treatment of the trimethyl derivative [Ti(eta5-C5Me5)Me3] with NH3 at room temperature leads to the trinuclear imido-nitrido complex [[Ti(eta/5-CsMes)(mu-NH)]3(mu3-N)] (2) via the intermediate [[Ti(eta5-C5Me5)Me]2(mu-NH)2] (3). The analogous reaction of [Ti(eta5-C5Me5)Me3] with 2,4,6-trimethylaniline (ArNH2) gives the dinuclear imido complex [[Ti(eta5-C5Me5)Me])2(mu-NAr)2] (4) which reacts with ammonia to afford [[Ti(eta5-C5Me5)(NH2)]2(mu-NAr)2] (5). Complex 2 has been used, by treatments with the tris(dimethylamido) derivatives [Ti(eta5-C5H5-nRn)(NMe2)3], as precursor of the cubane nitrido systems [[Ti4(eta5-C5Me5)3(eta5-C5H5-nRn)](mu3-N)4] [R = Me n = 5 (1), R = H n = 0 (6), R = SiMe3 n = 1 (7), R = Me n = 1 (8)] via dimethylamine elimination. Reaction of [Ti(eta5-C5Me5)Cl3] or [Ti(eta5-C5Me5)(NMe2)Cl2] with excess of ammonia at room temperature gives the dinuclear complex [[Ti2(eta5-C5Me5)2Cl3(NH3)](mu-N)] (9) where an intramolecular hydrogen bonding and a nonlineal nitrido ligand bridge the "Ti(eta5-C5Me5)Cl(NH3)" and "Ti(eta5-C5Me5)Cl2" moieties. The molecular structures of [[Ti(eta5-C5Me5)Me]2 (mu-NAr)2] (4) and [[Ti2(eta5-C5Me5)2Cl3(NH3)](mu-N)] (9) have been determined by X-ray crystallographic studies. Density functional theory calculations also have been conducted on complex 9 to confirm the existence of an intramolecular N-H...Cl hydrogen bond and to evaluate different aspects of its molecular disposition.     

Theoretical Study of Geometric Structures for Ground-state Al_nC（n=2-7） Clusters

With the aid of the molecular orbital DMol3 program,the energetics and electronic structures of several AlnC(n = 2-7) configurations have been searched and calculated by improved minimum energy paths(MEPs) by setting "imaging product".A new high symmetry,supervalence isomer of Al5C cluster,i.e.,D5h-Al5C,at the local minimum in the MEPs is detected.Several parameters,such as binding energy,HOMO-LUMO energy gap,vertical electron detachment energy and electron affinity energy,are calculated to characterize and evaluate the stability of three Al5C configurations,i.e.,D5h-Al5C,Cs-Al5C and C1-Al5C.The results show that the D5h-Al5C cluster is the ground state structure instead of Cs-Al5C.Due to the formation of many central σ bonds after polymerizing for D5h-Al5C,the decrease of the energy for HOMO orbit results in more territory for HOMO electrons of dislocation effect,then the energy difference between HOMO and LUMO is increasing to enhance the stability of molecules to produce such supervalence structure of Al5C cluster.The configuration evolution between D5h-Al5C,Cs-Al5C and C1-Al5C and the synthesis preference in the mode of Al5 + C → Al5C reveals that the Cs-Al5C and C1-Al5C con-figurations are permissive to coexist with D5h-Al5C structure in energetics.     

杂元素冠醚研究(Ⅻ)──氧、硫、硒和碲杂冠醚的液膜迁移性能比较

报道了碲杂冠醚(TeB15C5)对Na⁺、K⁺、Ag⁺和Pb²⁺的液膜迁移能力,并与相应的全氧冠醚(B15C5)、硫杂冠醚(SB15C5)和硒杂冠醚(SeB15C5)作了比较;同时以SeB15C5对K⁺的迁移为例考察了冠醚浓度和盐浓度对迁移速率的影响,结果表明,TeB15C5对Na⁺、K⁺和Pb²⁺的迁移能力比SB15C5和SeB15C5强,但对Ag⁺的迁移速率比后两者慢;SeB15C5对Ag⁺的迁移速度比SB15C5快,两者对Ag⁺的选择性都相当高,可以用来分离和回收银等贵重金属。     

Synthetic, reactivity, and structural studies on half-sandwich (eta5-C5Me5)Be and related compounds: halide, alkyl, and iminoacyl derivatives

The half-sandwich compounds [(eta(5)-C(5)Me(5))BeX] (X=Cl, 1 a; Br, 1 b), readily prepared from the reaction of the halides BeX(2) and M[C(5)Me(5)] (M=Na or K), are useful synthons for other (eta(5)-C(5)Me(5))Be organometallic compounds, including the alkyl derivatives [(eta(5)-C(5)Me(5))BeR] (R=Me, 2 a; CMe(3), 2 b; CH(2)CMe(3), 2 c; CH(2)Ph, 2 d). The latter compounds can be obtained by metathetical exchange of the halides 1 with the corresponding lithium reagent and exhibit NMR signals and other properties in accord with the proposed formulation. Attempts to make [(eta(5)-C(5)Me(5))BeH] have proved fruitless, probably due to instability of the hydride toward disproportionation into [Be(C(5)Me(5))(2)] and BeH(2). The half-sandwich iminoacyl [(eta(5)-C(5)Me(5))Be(C(NXyl)Cp')] and [(eta(5)-C(5)Me(4)H)Be(C(NXyl)Cp')]3, 6 where Xyl=C(6)H(3)-2,6-Me(2) and Cp'=C(5)Me(5) or C(5)Me(4)H, are formed when the beryllocenes [Be(C(5)Me(5))(2)], [Be(C(5)Me(4)H)(2)], and [Be(C(5)Me(5))(C(5)Me(4)H)] are allowed to react with CNXyl. Isolation of three different iminoacyl isomers from the reaction of the mixed-ring beryllocene [(eta(5)-C(5)Me(5))Be(eta(1)-C(5)Me(4)H)] and CNXyl, namely compounds 5 a, 5 b, and 6, provides compelling evidence for the existence in solution of different beryllocene isomers, generated in the course of two very facile processes that explain the solution dynamics of these metallocenes, that is the 1,5-sigmatropic shift of the Be(eta(5)-Cp') unit around the periphery of the eta(1)-Cp' ring, and the molecular inversion rearrangement that exchanges the roles of the two rings.     

As-5、[As5M]-、[As5MAs5]2- (M=Ti,Zr, Hf)的结构和芳香性

用密度泛函理论(DFT)研究了As-5、[As5M]-和[As5MAs5]2- (M=Ti, Zr, Hf)的结构、频率、能量以及芳香性, 详细讨论了体系中不同类型的键和电子如化学键、孤对电子、核电子等对总的核独立化学位移(NICS)的影响. 结果表明, As-5、[As5M]-和[As5MAs5]2-的基态结构分别具有D5h、C5v和D5h对称性, 而且都具有芳香性. As-5 (D5h)的芳香性主要来源于As—As π键和As—As σ键的作用. [As5M]-(C5v)中各种As—M键的NICS分割值占主要优势, 其次是As—As之间形成的σ键. [As5TiAs5]2-(D5h)中, As—As π键的作用占主要优势. [As5ZrAs5]2-(D5h)中, As—As π键对体系总的NICS贡献相对减小, 而As—Zr键的作用增强. [As5HfAs5]2-(D5h)的芳香性主要来自As—Hf键的作用.     

47, 49Ti NMR spectra of half-sandwich titanium(IV) complexes

The 47, 49Ti chemical shifts, resonance line half-widths (Deltanu1/2) and energies of the first electronic charge-transfer transitions (lambdamax1.CT) of Cp'TiX3, where Cp' = eta5-C5H5 (Cp), eta5-C5H4Me (MeCp), eta5-C5HMe4 (Me4Cp), eta5-C5Me5 (Me5Cp), eta5-C5H4SiMe3 (SiCp), eta5-C5H4SnMe3 (SnCp) and eta5-C5H4SiMe2Cl (Si'Cp) and X = Cl, Br, I and OBut, half-sandwich complexes are reported. For the compounds studied, a direct linear relationship between delta(49Ti) and lambdamax1.CT was found.     

苯丙烯类葡萄糖氧苷的合成及其抗缺氧活性

以取代苯甲醛(1a~1t)为原料,通过Knoevenagel缩合、酯化和LiAlH₄还原等反应制得苯丙烯醇衍生物(3a~3t);以取代肉桂醛(1u~1x)为原料,经NaBH₄还原制得苯丙烯醇衍生物(3u~3x); 3a~3x与全乙酰化溴代葡萄糖经Koenigs-Knorr偶联反应及MeONa/MeOH体系脱除乙酰保护基反应,合成了24个苯丙烯类葡萄糖氧苷(5a~5x),其中5c,5f ~ 5x为新化合物,其结构经¹H NMR和ESI-MS表征。采用MTT法测定了5对缺氧损伤的内皮细胞(EA.hy926)的抗缺氧活性。实验结果表明： 5b, 5e, 5g, 5p, 5q, 5s, 5t和5y对EA.hy926的抗缺氧活性均高于经景天苷。     

On the nature of actinide- and lanthanide-metal bonds in heterobimetallic compounds

Eleven experimentally characterized complexes containing heterobimetallic bonds between elements of the f-block and other elements were examined by quantum chemical methods: [(η(5)-C(5)H(5))(2)(THF)LuRu(η(5)-C(5)H(5))(CO)(2)], [(η(5)-C(5)Me(5))(2)(I)ThRu(η(5)-C(5)H(5))(CO)(2)], [(η(5)-C(5)H(5))(2)YRe(η(5)-C(5)H(5))(2)], [{N(CH(2)CH(2)NSiMe(3))(3)}URe(η(5)-C(5)H(5))(2)], [Y{Ga(NArCh)(2)}{C(PPh(2)NSiH(3))(2)}(CH(3)OCH(3))(2)], [{N(CH(2)CH(2)NSiMe(3))(3)}U{Ga(NArCH)(2)}(THF)], [(η(5)-C(5)H(5))(3)UGa(η(5)-C(5)Me(5))], [Yb(η(5)-C(5)H(5)){Si(SiMe(3))(3)(THF)(2)}], [(η(5)-C(5)H(5))(3)U(SnPh(3))], [(η(5)-C(5)H(5))(3)U(SiPh(3))], and (Ph[Me]N)(3)USi(SiMe(3))(3). Geometries in good agreement with experiment were obtained at the density functional level of theory. The multiconfigurational complete active space self-consistent field method (CASSCF) and subsequent corrections with second order perturbation theory (CASPT2) were applied to further understand the electronic structure of the lanthanide/actinide-metal (or metal-metalloid) bonds. Fragment calculations and energy-decomposition analyses were also performed and indicate that charge transfer occurs from one supported metal fragment to the other, while the bonding itself is always dominated by ionic character.     

Synthesis of new aryl substituted furan-2(5H)-ones using the Suzuki-Miyaura reaction

A series of novel 5-arylidenefuran-2(5H)-ones and 5-arylidene-4-arylfuran-2(5H)-ones were synthesized via the Suzuki-Miyaura reactions of fimbrolide derivatives 5-(bromomethylene)furan-2(5H)-one and 4-bromo-5-(bromomethylene)furan-2(5H)-one, respectively. A regioselective Suzuki-Miyaura reaction on 4-bromo-5-(bromomethylene)furan-2(5H)-one allowed the synthesis of unsymmetrically substituted 5-arylidene-4-arylfuran-2(5H)-ones. The crystal structure of the intermediate 5-arylidene-4-bromofuran-2(5H)-one revealed interesting Br?O halogen bonding.     

Synthesis of (C5Me5)2(C5Me4H)UMe, (C5Me5)2(C5H5)UMe, and (C5Me5)2UMe[CH(SiMe3)2] from cationic metallocenes for the evaluation of sterically induced reduction

To probe the correlation of unusual (C5Me5)(1-) reactivity with steric crowding in complexes such as (C5Me5)3UMe and (C5Me5)3UCl, slightly less crowded (C5Me5)2(C5Me4H)UX analogues (X = Me, Cl) were synthesized and their reactivity was evaluated. The utility of the cationic precursors [(C5Me5)2UMe](1+), 1, and [(C5Me5)2UCl](1+), 2, in the synthesis of (C5Me5)2(C5Me4H)UMe, 3, and (C5Me5)2(C5Me4H)UCl, 4, was also explored. Since the use of precursor [(C5Me5)2UMe][MeBPh3], 1a, is complicated by the equilibrium between 1a and (C5Me5)2UMe2/BPh3, the reactivity of [(C5Me5)2UMe(OTf)]2, 1b, (OTf = O3SCF3) prepared from (C5Me5)2UMe2 and AgOTf, was also studied. Both 1a and 1b react with KC5Me4H to form 3. Complex 4 readily forms by addition of KC5Me4H to [(C5Me5)2UCl][MeBPh3], generated in situ from (C5Me5)2UMeCl and BPh3. Complex 1b was preferred to 1a for the synthesis of (C5Me5)2(C5H5)UMe, 5, and (C5Me5)2UMe[CH(SiMe3)2], 6, from KC5H5 and LiCH(SiMe3)2, respectively. Complex 6 is the first example of a mixed alkyl uranium metallocene complex. Sterically induced reduction (SIR) reactivity was not observed with 3-6 although the methyl displacements from the (C5Me5)(1-) ring plane for 3 are the closest observed to date to those of SIR-active complexes. The (1)H NMR spectra of 3 and 4 are unusual in that all of the (C5Me4H)(1-) methyl groups are inequivalent. This structural rigidity is consistent with density-functional theory calculations.     

过渡金属μ3-E立方烷簇合物(η ^5-C5H5)4Fe4(μ3-Se)4及 (η ^5-RC5H4) 4Cr4(μ3-S)4的合成与表征

通过 (η5 C5H5) 2 Fe2 (CO) 4和硒粉在沸腾的甲苯中反应可制得含 μ3 Se的立方烷簇合物 (η5 C5H5) 4Fe4 (μ3 Se) 4(1) ,而由 (η5 RC5H4 ) 2 Cr2 (CO) 4S在甲苯中回流可制得含 μ3 S的立方烷簇合物 (η5 RC5H4 ) 4Cr4 (μ3 S) 4(2 ,R =COMe ;3,R =CO2 Me)。企图通过 (η5 EtO2 CC5H4 ) 2 Fe2 (CO) 4(5 )和硫黄制备 μ3 S立方烷簇合物 (η5 EtO2 CC5H4 ) 4Fe4 (μ3 S) 4(6 )未获成功 ,其中 5是由 η5 EtO2 CC5H4 Fe(CO) 2 Na与 η5 EtO2 CC5H4 Fe(CO) 2 I (4 )缩合制得。新化合物 1～ 5经元素分析 ,IR和1 HNMR光谱表征     

Mo/HZSM-5丙烷芳构化催化性能及其吸附量热的研究

采用等量浸渍法制得一系列不同担载量的Ｍｏ／ＨＺＳＭ－５催化剂,运用ＸＲＤ和ＦＴＩＲ方法考察了Ｍｏ物种在催化剂表面的分散状态,首次采用微分吸一热技术对Ｍｏ／ＨｚＳＭ－５催化剂的表面酸性进行表征。同时研究了催化剂对丙烷芳构化的反应活性。结果表明：对于担载Ｍｏ的ＨＺＳＭ－５分子筛催化剂,Ｍｏ物种在ＨＺＳＭ－５分子筛表面上顺序为ＨＺＳＭ－５〉１％Ｍｏ／ＨＺＳＭ－５〉２％Ｍｏ／ＨＺＳＭ－５分子筛本身表面的酸     

聚酰胺-胺型树枝状高分子水溶液的表面活性

树枝状化合物是一类三维的、高度有序的新型高分子.与传统高分子相比,这类化合物在合成时,可以在分子水平上严格控制,设计分子大小、形状、结构和功能基团,产物一般高度对称,单分散性好.因而具有广泛的潜在用途^[1,2].近年来,已引起广大化学工作者的重视.     

Novel coordinatively unsaturated bimetallic complexes, [(eta5-C5Me5)Ru(mu2-iPrNC(Me)=N(i)Pr)Ru(eta5-C5Me5)]+: a bridging amidinate ligand perpendicular to the metal-metal axis effectively stabilizes the highly reactive cationic diruthenium species.

Coordinatively unsaturated diruthenium complexes, [(eta5-C5Me5)Ru(mu2-iPrNC(Me)=NiPr)Ru(eta5-C5Me5)]+, of which crystallography revealed structures bearing a bridging amidinate ligand perpendicular to the Ru-Ru axis, were synthesized by anion exchange of [(eta5-C3Me5(Ru(mu2-iPrNC(Me)=NiPr)Ru(eta5-C5Me5)]+ Br- by weakly coordinating anions. Variable-temperature NMR showed rapid motion of the bridging amidinate ligand. The coordinatively unsaturated nature of the cationic complexes provides their high reactivity toward a series of two electron donor ligands. Oxidative addition of molecular hydrogen occurred to give [(eta5-C5Me5)Ru(mu2-iPrNC(Me)=NiPr)(mu-H)Ru(eta5-C5Me5)(H)]+, which was isolated and characterized.     

几个新型二茂铁衍生物的合成

二茂铁及其衍生物作为油类消烟剂、燃速催化剂等已得到应用,在药物、合成材料等方面亦具有应用前景。文献曾报道含二茂铁基β-二酮的合成及以它为配体的金属配合物。此类配合物均含两个以上金属原子,它们在有机合成中具有独特的催化活性。 我们将二茂铁甲酰丙酮分别与水扬酰肼、异菸肼、乙二胺及硫代氨基脲在甲醇或甲醇-水介质中进行缩合反应,合成了4个新型二茂铁衍生物,它们含有三个或四个配位功能基团,可作为多齿配体用于金属有机配合物的合成。衍生物的合成路线如下:     

5-氟尿嘧啶-1-乙酸合铜(Ⅱ)的合成及其与DNA的作用

The 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) were synthesized and the date for the crystal complex was obtained. The interaction of 5-fluorouracil-1-acetic acid (5FuAA) and its Cu(Ⅱ) complex (5FuAACu) with DNA was also investigated by using spectral, viscometric, electrochemical and agarose gel electrophoresis methods. The results of interaction with DNA suggest that both 5FuAA and 5FuAACu can bind to DNA in a static electricity attraction mode. But the attraction of 5FuAACu is greater than that of 5FuAA.     

Synthetic utility of [(C5Me5)2Ln][(mu-Ph)2BPh] in accessing [(C5Me5)2LnR]x unsolvated alkyl lanthanide metallocenes, complexes with high C-H activation reactivity

The loosely ligated [BPh4]1- ion in [(C5Me5)2Ln][(mu-Ph)2BPh2] can be readily displaced by alkyllithium or potassium reagents to provide access to unsolvated alkyl lanthanide metallocenes, [(C5Me5)2LnR]x, which display high C-H activation reactivity. [(C5Me5)2SmMe]3, [(C5Me5)2LuMe]2, [(C5Me5)2LaMe]x, (C5Me5)2Sm(CH2Ph), [(C5Me5)2Sm(CH2SiMe3)]x, and [(C5Me5)2SmPh]2 were prepared in this way. [(C5Me5)2SmMe]3 metalates toluene, benzene, SiMe4, and (C5Me5)1- ligands to make (C5Me5)2Sm(CH2Ph), [(C5Me5)2SmPh]2, [(C5Me5)2Sm(CH2SiMe3)]x, and (C5Me5)6Sm4[C5Me3(CH2)2]2, respectively. These C-H activation reactions can be done using an in situ synthesis of [(C5Me5)2LnMe]x such that the [(C5Me5)2Ln][(mu-Ph)2BPh2]/LiMe/RH combination provides a facile route to a variety of unsolvated [(C5Me5)2LnR]x products.