三嗪吡唑类铜配合物的合成、结构及光谱研究

以三齿吡唑-三嗪(类蝎型)化合物2,4-二(3,5-二甲基吡唑)-6-二乙基胺-1,3,5-三嗪(bpz^*eaT)为配体,在无水乙醇和甲醇溶剂中,合成了2个配合物Cu₂(mpz^*eaT-EtO)₂(N₃)₂Cl₂(1)和Cu₂(mpz^*eaT-MeO)₂(N₃)₄(2)(mpz^*eaT-EtO：2-(3,5-二甲基吡唑)-4-乙醇-6-二乙基胺-1,3,5-三嗪;mpz^*eaT-MeO：2-(3,5-二甲基吡唑)-4-甲醇-6-二乙基胺-1,3,5-三嗪)。通过元素分析、红外光谱、紫外光谱、热重分析以及X-ray单晶衍射方法对配合物进行了表征,并分析了其光谱及结构特征。晶体结构表明,配合物1属于三斜晶系,P1空间群,a=0.9949(2)nm,b=1.0216(2)nm,c=1.1480(2)nm,α=115.11(3)°,β=106.99(3)°,γ=100.39(3)°,V=0.9460(3)nm³,Z=1;配合物2属于单斜晶系,P2₁/c空间群,a=1.5464(5)nm,b=1.4008(5)nm,c=0.8905(3)nm,β=103.227(5)°,V=1.8779(10)nm³,Z=2。配合物1和2中的中心铜原子均为五配位,形成扭曲的四角锥构型。     

1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮稀土配合物的合成、晶体结构、发光性能与密度泛函理论计算

以1-苯基-3-甲基-4-苯甲酰基-5-吡唑啉酮(Hpmbp)和4,4′-二甲基-2,2′-联吡啶(dmbipy)为配体合成了一类单核稀土配合物[Ln(pmbp)₃(dmbipy)]·C₂H₅OH,其中 Ln=Tb (1-Tb)、Ho (1-Ho)、Er (1-Er)、Tm (1-Tm)。结构表征显示该类配合物由稀土金属离子与3个pmbp^-配体、1个dmbipy配体配位而成,同时存在一分子非配位的乙醇。Ln³⁺离子的配位环境均接近于三角十二面体构型。荧光测试表明,1-Tb、1-Ho、1-Er和1-Tm均表现出了相应稀土离子的特征发射峰。此外,利用密度泛函理论计算分析了Hpmbp配体、dmbipy配体及稀土配合物的HOMO-LUMO信息。     

有机锡9-芴酮-4-甲酸酯的合成、结构及抗癌活性

合成了 3 个有机锡 9-芴酮-4-甲酸酯:三苯基锡 9-芴酮-4-甲酸酯[(C₆H₅)₃Sn(C₁₄H₇O₃)] (1)、三环己基锡 9-芴酮-4-甲酸酯[(C₆H₁₁)₃Sn(C₁₄H₇O₃)] (2)和三(2-甲基-2-苯基丙基)锡 9-芴酮-4-甲酸酯[(C₆H₅C(CH₃)₂CH₂)₃Sn(C₁₄H₇O₃)] (3)。通过元素分析、红外光谱、核磁共振谱(¹H、¹³C和 ¹¹⁹Sn)、热重分析进行了表征;用单晶X射线衍射方法测定了化合物的晶体结构,并对其进行了量子化学计算和体外抗癌活性研究。结果显示:化合物1为一维链状结构,中心锡原子为五配位的畸变三角双锥构型;化合物2和3均为单核分子,锡原子均为四配位的畸变四面体构型。化合物对人宫颈癌细(HeLa)、人肝癌细胞(HUH-7)、人非小细胞肺癌细胞(A549)、人肺腺癌细胞(H1975)和人乳腺癌细胞(MCF-7)都有较好的抑制活性。     

钴(Ⅲ)催化CpCoS2C2B10H10分子内B(3)/B(6)位和Cp配体偶联

半夹芯16e化合物CpCoS₂C₂B₁₀H₁₀(Cp:cyclopentadienyl) (1)与HC≡CCO₂Me在2-甲基二硫代丙酸存在下反应生成化合物{(C₅H₄CoS₂C₂B₉H₉)(CH=CHCO₂Me)(Me₂C=CS₂H)} (2)和(Me₂C=CS₂H)₃Co (3)。在化合物2中, 原料化合物1中的一个S-Co键断裂, 该S原子与一分子HC≡CCO₂Me末端炔基碳原子连接。Co原子与2-甲基二硫代丙酸的S原子连接成键, 2-甲基二硫代丙酸分子中的SH基团与Co原子通过配位键相连;同时, Cp环的一个碳原子与碳硼烷笼体的B(3)/B(6)位相连, 该B(3)/B(6)位的氢原子迁移到炔烃HC≡CCO₂Me的内部炔基碳原子上形成反式烯键。3个2-甲基二硫代丙酸分子中的3个S原子分别与1中的Co原子通过共价键连接, 3个SH基团与Co原子通过配位键相连, 从而形成化合物3。化合物2和3分别用红外、核磁、元素分析、质谱和单晶X-射线衍射分析等方法进行了表征。     

钴(Ⅲ)催化CpCoS2C2B10H10分子内B(3)/B(6)位和Cp配体偶联

半夹芯16e化合物CpCoS₂C₂B₁₀H₁₀(Cp：cyclopentadienyl) (1)与HC≡CCO₂Me在2-甲基二硫代丙酸存在下反应生成化合物{(C₅H₄CoS₂C₂B₉H₉)(CH=CHCO₂Me)(Me₂c=CS₂H)} (2)和(Me₂c=CS₂H)₃Co (3)。在化合物2中, 原料化合物1中的一个S-Co键断裂, 该S原子与一分子HC≡CCO₂Me末端炔基碳原子连接。Co原子与2-甲基二硫代丙酸的S原子连接成键, 2-甲基二硫代丙酸分子中的SH基团与Co原子通过配位键相连;同时, Cp环的一个碳原子与碳硼烷笼体的B(3)/B(6)位相连, 该B(3)/B(6)位的氢原子迁移到炔烃HC≡CCO₂Me的内部炔基碳原子上形成反式烯键。3个2-甲基二硫代丙酸分子中的3个S原子分别与1中的Co原子通过共价键连接, 3个SH基团与Co原子通过配位键相连, 从而形成化合物3。化合物2和3分别用红外、核磁、元素分析、质谱和单晶X-射线衍射分析等方法进行了表征。     

苯基-吡唑铜(Ⅱ)和钴(Ⅱ)配合物的合成、结构及其仿生催化溴化活性

在无水乙醇体系中设计合成了2种配合物:[Cu(L₁)Cl₂]·0.5C₂H₅OH(1)和Co(L₁)Cl₂(2)(L₁=1,4-双(吡唑甲基)苯)。通过元素分析、红外光谱、热重、X-射线粉末和X-射线单晶衍射方法对其结构进行了表征,分析了其光谱及结构特征。结构分析表明,配合物1中金属配位数为5,形成四角锥构型,配合物2的中心金属配位数为4,形成了扭曲四面体构型,配体1,4-双(吡唑甲基)苯采取二齿桥联配位模式。通过仿生催化溴化动力学研究,发现上述配合物均表现出潜在的催化溴化活性。     

新型多氨-多酰氨配体和氨基酸的三元铜(Ⅱ)配合物(英)

合成3个多氨-多酰氨配体1，12-二((α-羟甲基)苯基)-2，5，8，11-四氮杂十二烷-1，12-二酮(L₁)，1，13-二((α-羟甲基)苯基)-2，5，9，12-四氮杂十三烷-1，13-二酮(L₂)，1，15-二((α-羟甲基)苯基)2，5，8，11，14-五氮杂十五烷-1，15-二酮（L₃）。利用pH滴定分别在5.0 ℃，15.0 ℃，25.0 ℃，35.0 ℃测定了铜(Ⅱ)与这3种配体在     

吡啶-2-羧酸的Dy(Ⅲ)和Tm(Ⅲ)配合物及其与牛血清白蛋白结合性能

以5-(三氟甲基)吡啶-2-羧酸(Htpc)与DyCl₃·6H₂O、TmCl₃·3H₂O构筑了2种异质同晶的单核配合物[M(tpc)₃(H₂O)₃]·H₂O,其中 M=Dy (1)、Tm (2)。配合物 1 和 2 均为单斜晶系,P2₁/c 空间群,中心金属离子为八配位且形成了轻微扭曲的十二面体构型。温度梯度下的荧光和紫外测试表明,2 种配合物均能与牛血清白蛋白(BSA)发生静态猝灭作用,猝灭常数(K_sv)为 10⁵~10⁶ L·mol^-1。配合物与BSA结合过程的ΔH和ΔS均为正值,说明疏水作用在其中扮演重要的角色。25℃时,2种配合物与BSA结合常数约为10⁴ L·mol^-1,表明二者与BSA的具有中等强度的结合力。     

超声辐射下合成1-[(未)取代苯酰基-3-[5-(1-苯基-3-甲基-5-氯吡唑-4-基)-1,3,4-噻二唑-2-基]-硫脲

1-苯基-3-甲基-5-氯吡唑-4-甲酸与氨基硫脲在三氯氧磷中反应得到2-氨基-5-(1-苯基-3-甲基-5-氯吡唑-4-基)-1,3,4-噻二唑(1), 然后分别采用超声辐射法和常规加热法与(未)取代苯甲酰基异硫氰酸酯(2)反应合成了一系列未见报到的1-[(未)取代苯酰基-3-[5-(1-苯基-3-甲基-5-氯吡唑-4-基)-1,3,4-噻二唑-2-基]-硫脲(3a～3j). 化合物的结构经元素分析, IR, ¹H NMR确证.     

二(2-吡啶甲酸)二(邻氟苄基)锡和一维链状4-吡啶甲酸三(邻氟苄基)锡的合成和晶体结构

μ-氧-双[三(邻氟苄基)锡]与2-吡啶甲酸或4-吡啶甲酸在苯溶剂中反应合成有机锡配合物二(2-吡啶甲酸)二(邻氟苄基)锡(1)和一维链状4-吡啶甲酸三(邻氟苄基)锡(2)，经X射线衍射方法测定了新化合物的晶体结构。配合物(1)属四方晶系，空间 群为I4₁/a，晶体学参数：a=1.562 0(3) nm，b=1.562 0(3) nm，c=1.984 7(4) nm，α=β=γ=90°，V=4.842 4(16) nm³，Z=8,D_c=1.594 Mg·m^-3， μ(Mo Kα)=11.06 cm^-1，F(000)=2 320，R₁=0.024 3，wR=0.062 5。配合物(2)属单斜晶系，空间群为P2₁/n，晶体学参数：a=0.869 8(3) nm，b=1.880 5(7) nm，c=1.475 1(5) nm，β=90.937(6)°，V=2.412 3(15) nm³，Z=4，D_c=1.564 Mg·m^-3，μ(Mo Kα)=11.07 cm^-1，F(000)=1 136，R₁=0.028 8，wR₂=0.057 9；配合物1为单体结构，中心锡为六配位畸变八面体构型。配合物2通过4-吡啶甲酸配体氮原子的桥联，形成五配位三角双锥型的链状结构。     

Heterometallic cluster complexes (RhMo, RhW) containing bridging 1,2-dicarba-closo-dodecaborane-1,2-dichalocogenolato ligands

The 16-electron half-sandwich rhodium complex [Cp*Rh{E2C2(B10H10)}] [Cp* = eta5-C5Me5, E = S (1a), Se (1b)] [Cp*Rh{E2C2(B10H10)} = eta5-pentamethylcyclopentadienyl[1,2-dicarba-closo-dodecaborane(12)-dichalcogenolato]rhodium] reacted with Mo(CO)3(py)3 in the presence of BF3.Et2O in THF solution to afford the {Cp*Rh[E2C2(B10H10)]}2Mo(CO)2 (E = S (3a); Se (3b)), {Cp*Rh[S2C2(B10H10)]}{Mo(CO)2[S2C2(B10H10)]} (4). The voluminous di-tert-butyl substituted Cp half-sandwich rhodium complex [Cp'Rh{E2C2(B10H10)}] [E = S (2a), Se (2b)] [CpRh{E2C2(B10H10)} = eta5-(1,3-di(tert-butyl)cyclopentadienyl-[1,2-dicarba-closo-dodecaborane(12)-dichalcogenolato]rhodium) reacted with W(CO)3(py)3 in the presence of BF3.Et2O in THF solution to give the {Cp'Rh[S2C2(B10H10)]}{W(CO)2[S2C2(B10H10)]} (5) and {Cp'Rh[Se2C2(B10H10)]}(mu-CO)[W(CO)3] (6), respectively. The complexes have been fully characterized by IR and NMR spectroscopy as well as by elemental analyses. The X-ray crystal structures of the complexes 3-6 are reported.     

Preparation of chalcogenolato-bridged dinuclear Tp*Rh-Cp*Ru complexes (Tp*= hydrotris(3,5-dimethylpyrazol-1-yl)borate, Cp*=eta(5)-pentamethylcyclopentadienyl) and binding of dioxygen to their Ru sites

Reactions of [Tp*Rh(coe)(MeCN)](1; Tp*= hydrotris(3,5-dimethylpyrazol-1-yl); coe = cyclooctene) with one equiv of diphenyl dichalcogenides PhEEPh (E = Se, Te) afforded the mononuclear Rh(III) complexes [Tp*Rh(EPh)(2)(MeCN)](2b: E = Se; 2c: E = Te), as reported previously for the formation of [Tp*Rh(SPh)(2)(MeCN)](2a) from the reaction of 1 and PhSSPh. Complexes 2a-2c were treated with the Ru(II) complex [(Cp*Ru)(4)(mu(3)-Cl)(4)](Cp*=eta(5)-C(5)Me(5)) in THF at room temperature, yielding the chalcogenolato-bridged dinuclear complexes [Tp*RhCl(mu-EPh)(2)RuCp*(MeCN)](3). Complex 3a (E = S) in solution was converted slowly into a mixture of 3a and the sterically less encumbered dinuclear complex [Tp*RhCl(SPh)(mu-eta(1)-S-eta(6)-Ph)RuCp*](4a) at room temperature. In 4a, one SPh group binds only to the Rh center as a terminal ligand, while the other SPh group bridges the Rh and Ru atoms by coordinating to the former at the S atom and to the latter with the Ph group in a pi fashion. The Se analogue 3b also underwent a similar transformation under more forcing conditions, e.g. in benzene at reflux, whereas formation of the mu-eta(1)-Te-eta(6)-Ph complex was not observed for the Te analogue 3c even under these forcing conditions. When complexes 3 was dissolved in THF exposed to air, the MeCN ligand bound to Ru was substituted by dioxygen to give the peroxo complexes [Tp*RhCl(mu-EPh)(2)RuCp*(eta(2)-O(2))](5a: E = S; 5b: E = Se; 5c: E = Te). X-Ray analyses have been undertaken to determine the detailed structures for 2c, 3a, 3b, 4a, 5a, 5b, and 5c.     

Synthesis and structure of heterometallic complexes (RhFe, CoFe) containing bridging 1,2-dicarba-closo-dodecarborane-1,2-dichalcogenolato ligands

The prototype hetero-binuclear complexes containing metal-metal bonds, {CpRh[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(5a), Se(5b); Cp = Cp = eta 5-1,3-tBu2C5H3, E = S(6a), Se(6b)) and {CpCo[E2C2(B10H10)]}[Fe(CO)3] (Cp = Cp* = eta 5-Me5C5, E = S(7a), Se(7b); Cp = Cp = eta 5-C5H5, E = S(8a), Se(8b)) were obtained from the reactions of 16-electron complexes CpRh[E2C2(B10H10)] (Cp = Cp*, E = S(1a), Se(1b); Cp = Cp, E = S(2a), Se(2b)), CpCo[E2C2(B10H10)] (Cp = Cp*, E = S(3a), Se(3b); Cp = Cp, E = S(4a), Se(4b)) with Fe(CO)5 in the presence of Me3NO. The molecular structures of {Cp*Rh[E2C2(B10H10)]}[Fe(CO)3] (E = S(5a), Se(5b)), {CpRh[S2C2(B10H10)]}[Fe(CO)3] (6a) {Cp*Co[S2C2(B10H10)]}[Fe(CO)3] (7a) and {CpCo[S2C2(B10H10)]}[Fe(CO)3] (8a) have been determined by X-ray crystallography. All these complexes were characterized by elemental analysis and IR and NMR spectra.     

Syntheses and structures of heterometallic clusters by the reaction of o-carboranyl cobaltadichalcogenolato complexes

Metalladichalcogenolate cluster complexes [Cp'Co{E(2)C(2)(B(10)H(10))}]{Co2(CO)5} [Cp' = eta5-C5H5, E = S(3a), E = Se(3b); Cp' = eta5-C5(CH3)5, E = S(4a), E = Se(4b)], {CpCo[E(2)C(2)(B(10)H(10))]}(2)Mo(CO)2] [E = S(5a), Se(5b)], Cp*Co(micro2-CO)Mo(CO)(py)2[E(2)C(2)(B(10)H(10))] [E = S(6a), Se(6b)], Cp*Co[E(2)C(2)(B(10)H(10))]Mo(CO)2[E(2)C(2)(B(10)H(10))] [E = S(7a), Se(7b)], (Cp'Co[E(2)C(2)(B(10)H(10))]W(CO)2 [E(2)C(2)(B(10)H(10))] [Cp' = eta5-C5H5, E = S(8a), E = Se(8b); Cp' = eta5-C5(CH3)5, E = S(9a), E = Se(9b)], {CpCo[E(2)C(2)(B(10)H(10))]}(2)Ni [E = S(10a), Se(10b)] and 3,4-(PhCN(4)S)-3,1,2-[PhCN(4)SCo(Cp)S(2)]-3,1,2-CoC(2)B(9)H(8) 12 were synthesized by the reaction of [Cp'CoE(2)C(2)(B(10)H(10))] [Cp' = eta5-C5H5, E = S(1a), E = Se(1b); Cp' = eta5-C5(CH3)5, E = S(2a), E = Se(2b)] with Co2(CO)8, M(CO)3(py)3 (M = Mo, W), Ni(COD)2, [Rh(COD)Cl]2, and LiSCN4Ph respectively. Their spectrum analyses and crystal structures were investigated. In this series of multinuclear complexes, 3a,b and 4a,b contain a closed Co3 triangular geometry, while in complexes 5a-7b three different structures were obtained, the tungsten-cobalt mixed-metal complexes have only the binuclear structure, and the nickel-cobalt complexes were obtained in the trinuclear form. A novel structure was found in metallacarborane complex 12, with a B-S bond formed at the B(7) site. The molecular structures of 4a, 5a, 6a, 7b, 9a, 9b, 10a and 12 have been determined by X-ray crystallography.     

一些含半夹心结构ⅥB族金属的1,1’-二硫(硒)二茂铁化合物的合成

CpCr(NO)(CO)_2与Fe(C_5H_4S)_2S反应,形成氧化-还原产物CpCr(NO)(SC_5H_4)_2Fe(1)。双杂核二茂铁化合物CpM(NO)(EC_5H_4)_2Fe[M=Mo,E=S(2a),Se(2b);M=W,E=S(4a),Se(4b)]、CpMo(NO)(SC_5H_4)_2Fe(3)、Cp_2Mo(SeC_5H_4)_2Fe(6)和Cp_2W(SC_5H_4)_2Fe(7)可通过Fe(C_5H_4ELi)_2·2THF(E=S,Se)与CpM(NO)I_2(M=Mo,W)、[CpMo(NO)I_2]_2或Cp_2MCl_2(M=Mo,W)反应制得。三核杂原子二茂铁化合物[CpCr(NO)_2]_2(EC_5H_4)_2Fe[E=S(8a),Se(8b)],由Fe(C_5H_4ELi)_2·2THF(E=S,Se)与二倍摩尔量的CpCr(NO)_2I反应制备。通过AgBF_4氧化2a得到二茂铁离子型化合物[CpMo(NO)(SC_5H_4)_2Fe]~ BF_4~-(5)。采用元素分析、红外光谱、~1H和~(13)C NMR谱以及EI-MS表征了所合成的新型化合物。     

含半夹心结构铑的1,1'-二硫(硒、碲)二茂铁化合物

以半夹心结构铑的化合物Cp*Rh(CN^tBu)Cl2(1)(Cp*=η^5-C5Me5)与Fe(C5H4ELi)2.2THF反应,合成出异双核二茂铁化合物Cp*Rh(CN^tBu)(EC5H4)2Fe[E=S(2),Se(3),Te(4)]。通过AgBF4氧化2和3得到二茂铁离子型化合物[Cp*Rh(CN^tBu)(EC5H4)2Fe]BF4[E=S(5),Se(6)]。采用元素分析、红外光谱、^1H和13CNMR谱以及EI-MS表征了所合成的化合物。     

Synthesis, characterization, and biomimetic chemistry of cis-oxosulfidomolybdenum(VI) complexes stabilized by an intramolecular Mo(O)=S...S interaction

The reactions of jade-green Tp*MoIVO(S2PR2) [Tp* = hydrotris(3,5-dimethylpyrazol-1-yl)borate; R = Et, Pri, Ph] with propylene sulfide produce ochre-red Tp*MoVIOS{SP(S)R2}. The complexes have been characterized by microanalysis, mass spectrometry, cyclic voltammetry, spectroscopy (IR, NMR, UV-vis, and X-ray absorption), and X-ray crystallography. The distorted-octahedral isopropyl and phenyl derivatives feature a tridentate fac-Tp* ligand, a terminal oxo ligand, and a unique five-membered Mo(=S){SP(=S)R2 ring moiety formed by a weak, intramolecular, bonding interaction between the Mo=S1 and (uncoordinated) S3=P moieties. The Mo=S1 [2.227(2) A (R = Pri) and 2.200(2) A (R = Ph)] and S1...S3 distances [2.396(3) A (R = Pri) and 2.383(2) A (R = Ph)] are indicative of a pi-bonded Mo=S1 unit and a weak (bond order ca. 1/3) S1...S3 interaction; the solid-state structures are maintained in solution according to S K-edge X-ray absorption data. The complexes react with excess cyanide to form thiocyanate and Tp*MoO(S2PR2), under anaerobic conditions, or Tp*MoO2(S2PR2), under aerobic conditions; the latter models the production of thiocyanate and desulfo molybdenum hydroxylases upon cyanolysis of molybdenum hydroxylases. The complexes react with triphenylphosphine to give Tp*MoO(S2PR2) and SPPh3, with cobaltocene or hydrosulfide ion to produce [Tp*MoVOS(S2PR2)]-, and with ferrocenium salts to yield [Tp*MoVO(S3PR2)]+; in the last two reactions, Mo(V) is produced by direct or induced internal redox reactions, respectively. The presence of the Mo(O)=S...S interaction does not radically lengthen the Mo=S bond in the complexes or preclude them from reactions typical of unperturbed oxosulfidomolybdenum(VI) complexes.     

Preparation and structure of mono- and binuclear half-sandwich iridium, ruthenium, and rhodium carbene complexes containing 1,2-dichalcogenolao 1,2-dicarba-closo-dodecaboranes

The synthesis of half-sandwich transition metal complexes containing both 1,2-dichalcogenolato-1,2-dicarba-closo-docecaborane (Cab(E,E)) [Cab(E,E)=E(2)C(2)(B(10)H(10)); E = S, Se] and N-heterocyclic carbene (NHC) ligands is described. Addition of mono-NHC ligand to the 16e half-sandwich dichalcogenolato carborane complexes [Cp*Rh(Cab(E,E))], [Cp*Ir(Cab(S,S))], [(p-cymene)Ru(Cab(S,S))] (Cp* = pentamethylcyclopentadienyl) gives corresponding mononuclear 18e dithiolate complexes of the type [LM(Cab(E,E))(NHC)]: [Cp*M(Cab(S,S))(1-ethenyl-3-methylimidazolin-2-ylidene)] (M = Ir (2), Rh (3)), [Cp*Rh(Cab(E,E))(3-methyl-1-picolyimidazolin-2-ylidene)] [E = S (6), Se (7)], [(p-cymene)Ru(Cab(S,S))(NHC)] [NHC = 1-ethenyl-3-methylimidazolin-2-ylidene (4), 3-methyl-1-picolyimidazolin-2-ylidene (8)], whereas bis-NHC give centrosymmetric binuclear complexes [{Cp*M(Cab(S,S))}(2)(1,1'-dimethyl-3,3'-methylene(imidazolin-2-ylidene))] [M = Rh (10), Ir (11)]. The complexes were characterized by IR, NMR spectroscopy and elemental analysis. In addition, X-ray structure analyses were performed on complexes 2-4, 6, 8, 10 and 11.     

Construction of trinuclear iridium clusters through ancillary ortho-carborane-1,2-diselenolato ligands, with simultaneous iridium-induced B-H activation

The reaction of the 16-electron "pseudo-aromatic" complex Cp*Ir[Se2C2(B10H10)] (1, Cp* = eta5-C5Me5) with [Ir(cod)(micro-OC2H5)]2 leads to the trinuclear iridium complexes {(cod)Ir[Se2C2(B10H8)(OC2H5)]}Ir{[Se2C2(B10H10)]IrCp*} (2), {(cod)Ir[Se2C2(B10H8)(OC2H5)]}Ir{[Se2C2(B10H9)]IrCp*} (3), {Cp*Ir[Se2C2(B10H9)]}{IrSe(2)[C2(B10H9)(OC2H5)]}{[Se2C2(B10H10)] IrCp*} (4) and one mononuclear complex Cp*Ir[Se2C2(B10H8)(OC2H5)(2)] (5). The reactivity of 2 was investigated and revealed that transformation from 2 to 3 occurred thermally in solution. The transoid complex 2 (with the carborane diselenolato units in trans position) can be converted in nearly 90% yield to the cisoid complex 3. In complexes 2, 3, two diselenolato carborane ligands bridge the Ir(3) core, which consists of Ir-Ir metal bonds. Compared with transoid 2, the cisoid 3 contains two iridium-boron bonds. Complex 4 consists of three different coordination environment carborane ligands (Ir-B(cluster): {Cp*Ir[Se2C2(B10H9)]}, O-B(cluster): {[Se2C2(B10H9)](OC2H5)}, and intact carborane: {Cp*Ir[Se2C2 (B10H10)]}) without the presence of a metal-metal bond. Analogous reaction of 1 with [Ir(cod)(micro-OCH(3))](2) results in formation of the trinuclear complex {Cp*Ir[Se2C2(B10H9)]}{IrSe(2)[C2(B10H9)(OCH3)]}{[Se2C2(B10H10)]IrCp*} (6) and mononuclear complex Cp*Ir[Se2C2(B10H8)(OCH3)(2)] (7). The structures of 2, 3, 4, 5, 6 and 7 have been determined by crystallographic studies.     

Synthesis and characterisation of second-generation metallodithiolene complexes of the type [Tp*ME(dithiolene)](M=Mo, W; E=O, S) and a novel 'organoscorpionate' complex of tungsten

Paramagnetic, chalcogenido-M(v) dithiolene complexes, [Tp*ME{S2C2(CO2Me)2}][M=Mo, E=O, S; M=W, E=O, S; Tp*=hydrotris(3,5-dimethylpyrazol-1-yl)borate] are generated in the reactions of dimethyl acetylenedicarboxylate (DMAC) and the sulfur-rich complexes NEt4[Tp*MoS(S4)] and NEt4[Tp*WS3]; the oxo complexes result from hydrolysis of the initial sulfido products. As well, a novel 'organoscorpionate' complex, [W{S2C2(CO2Me)2}{SC2(CO2Me)2-Tp*}], has been isolated from the reactions of NEt4[Tp*WS3] with excess DMAC. Complexes , and have been isolated and characterised by microanalytical, mass spectrometric, spectroscopic and (for and) X-ray crystallographic techniques. Complexes and have been partially characterised by mass spectrometry and IR and EPR spectroscopy. Six-coordinate, distorted-octahedral contains a terminal sulfido ligand (W=S=2.108(3)A), a bidentate dithiolene ligand (S-Cav=1.758 A, C=C=1.332(10)A) and a fac-tridentate Tp* ligand. Seven-coordinate contains a planar, bidentate dithiolene ligand (S-Cav=1.746 A, C=C=1.359(5)A) and a novel pentadentate 'organoscorpionate' ligand formed by the melding of DMAC, sulfido and trispyrazolylborate units. The latter is coordinated through two pyrazolyl N atoms (kappa2-N,N') and a tridentate kappa3-S,C,C' unit appended to N-beta of the third (uncoordinated) pyrazolyl group. The second-generation [Tp*ME(dithiolene)] complexes represent a refinement on first-generation [Tp*ME(arene-1,2-dithiolate)] complexes and their synthesis affords an opportunity to compare and contrast the electronic structures of true vs. pseudo-dithiolene ligands in otherwise analogous complexes.