担载四核羰基簇:FeCo~3(CO)~11PPh 在聚苯乙烯表面簇骼畸变的EXAFS研究

通过配体取人工将四核羰基簇FeCo~3(CO) 锚联在膦化的聚苯乙烯表面,获得担载簇FeCO~3(CO)~11PPh/poly,目的在于使簇骼结构偏离较高对称性,以考察锚联过程对簇结构的影响.本文以EXAFS(Extended x-ray Absorption Fine Struature)方法研究了担载样品的结构.结果显示担载簇与FeCO~3(CO)~11PPh 晶体具有相同的结构模式,尤其是膦配体确实与一Co原子相连接.EXAFS结果表明:(1)与FeCO~3(CO) (其簇骼具有三重对称结构)比较,锚联使Co-Fe键增长0.005nm;金属-金属及金属-桥联碳壳层Debye-Waller因子均增大约一倍而金属一端联碳壳层的值变化很小.说明金属-金属间实际键长值具有一较宽分布,因而其簇骼已偏离了三重对称结构;(2)与FeCO~3(CO)~11PPh 晶体的结构比较,Co-Fe键长长0.003nm而Co-Co键长则短约0.002nm.考虑到EXAFS分析只能给出平均键长值,因此认为,存在于FeCO~3(CO)~11PPh 晶体中的由于一个羰基被膦配体取代而引起的簇骼畸变,在锚联后被加剧.     

担载四核羰基簇——FeCo_3(CO)_11PPh_3~-在聚苯乙烯表面簇骼畸变的EXAFS研究

通过配体取代将四核羰基簇FeCo_3(CO)_(12)~-锚联在膦化的聚苯乙烯表面,获得担载簇FeCo(?)(CO)_(11)PPh_3~-/poly,目的在于使簇骼结构偏离较高对称性.以考察锚联过程对簇结构的影响.本文以EXAFS(Extended X-ray Absorption Fine Structure)方法研究了担载样品的结构.结果显示担载簇与FeCo_3(CO)_(11)PPh_3~-晶体具有相同的结构模式,尤其是膦配体确实与一Co原子相连接.EXAFS结果表明:(1)与FoCo_3(CO)_(12)~-(其簇骼具有三重对称性结构)比较,锚联使Co—Fe键增长0.005nm;金属-金属及金属-桥联碳壳层的Debye-Waller因子均增大约一倍而金属-端联碳壳层的值变化很小.说明金属-金属间实际键长值具有一较宽分布,因而其簇骼已偏离了三重对称结构;(2)与FeCo_3(CO)_(11)PPh_3~-晶体的结构比较.Co—Fe键长长0.003nm.而Co—Co键长则短约0.002nm.考虑到EXAFS分析只能给出平均键长值,因此认为,存在于FeCo_3(CO)_(11)PPh_3~-晶体中的由于一个羰基被膦配体取代而引起的簇骼畸变,在锚联后被加剧.     

化学键联铁-钴四核羰基簇结构的EXAFS研究

本文以EXAFS方法研究了化学键联的四核铁-钴羰基簇[Co3Fe(CO)12]-的表面结构。结果显示担载后Co-Co键长缩短0.04埃, Co-C和Co-Fe键长分别增长0.03和0.08埃, 说明FeCO3的四面体簇骼在担载后更大地偏离开理想的正四面体。     

化学键联铁-钴四核羰基簇结构的EXAFS研究

本文以EXAFS方法研究了化学键联的四核铁-钴羰基簇[Co_(?)Fe(CO)_(12)]~-的表面结构。结果显示担载后Co—Co键长缩短0.04(?),Co—C和Co—Fe键长分别增长0.03和0.08(?),说明FeCo_3的四面体簇骼在担载后更大地偏离开理想的正四面体。     

膦化聚苯乙烯担载四核羰基钴簇的合成和催化作用

合成了两种含膦聚苯乙烯载体和此二载体与四核羰基钴簇CO_4(CO)_8(μ_2-CO_2(μ_4-PPh)_2通过配体交换反应,合成两种担载的金属原子簇催化剂.用IR、VU-DRS和XPS表征担载簇配合物的结构.考察了担载簇催化剂对讣茑烯烃的氢甲酰化反应的催化活性.其活性顺序为:1-庚烯>环己烯>二异丁烯>2-辛烯>苯乙烯.     

担载三核羰基钴簇的合成,表征和烯烃氢甲酰化反应

通过配体交换反应合成了膦化硅胶担载的羰基钴簇配合物(Si)—PPh_2[BrCCo_3(CO)_(9-2)],用IR、XPS和DPS对其结构进行了表征,并测得了担载簇配合物的金属含量,研究了担载簇(Si)—PPh_2[BrCCo_3(CO)_(9-2)]在烯烃氢甲酰化反应中的催化活性.结果表明,担载的三核羰基钴簇可达到与均相三核钴簇基本一致的反应活性,在一定的反应条件下,烯烃转化率和醇醛收率均在85％以上,有很少量的加氢产物生成。     

直接法合成异核羰基金属族合物及Pd3(SC6H4OH)3(PPh3)3(OH)2Cl的晶体结构分析

本文根据分子碎片结合原理, 用直接法由简单的单质元素, 金属盐类及配体, 通过控制反应温度、压力, 时间及配体用量在CO气氛下一步合成含羰基和不含羰基的簇合物: Pd3(SC6H4OH)3(PPh3)3(OH)2Cl(1),Fe2S2(CO)5Pd(PPh3)3(2), Fe2S2(CO)5Pt(PPh3)3(3)。对它们进行了IR, NMR,EDS, 元素分析, 金属分析和化合物1的X光单晶衍射结构分析。化合物1属单斜晶系, 离子型, P21/n空间群, 晶胞参数a=1.4629(3)nm, b=1.9263(3)nm,c=2.4908(7)nm, β=94.53(2)°, Z=4, R=0.053。     

直接法合成异核羰基金属族合物及Pd3(SC6H4OH)3(PPh3)3(OH)2Cl的晶体结构分析

本文根据分子碎片结合原理, 用直接法由简单的单质元素, 金属盐类及配体, 通过控制反应温度、压力, 时间及配体用量在CO气氛下一步合成含羰基和不含羰基的簇合物: Pd3(SC6H4OH)3(PPh3)3(OH)2Cl(1),Fe2S2(CO)5Pd(PPh3)3(2), Fe2S2(CO)5Pt(PPh3)3(3)。对它们进行了IR, NMR,EDS, 元素分析, 金属分析和化合物1的X光单晶衍射结构分析。化合物1属单斜晶系, 离子型, P21/n空间群, 晶胞参数a=1.4629(3)nm, b=1.9263(3)nm,c=2.4908(7)nm, β=94.53(2)°, Z=4, R=0.053。     

四面体异核金属羰基簇合物的合成、表征及单晶结构分析

利用金属交换反应, 使金属羰基配合物PhCCo~3(CO)~9和过渡金属配合物NaMo(CO)~3(RCp)在THF中回流反应, 制备出三个新的异核三金属羰基簇合物PhCCo~2Mo(CO)~8(RCp)(R=HCO, CH~3CO, C~2H~5O~2C)。结果表明, 与金属交换剂NaMo(CO)~3Cp相比较, 环戊二烯上吸电子基团C=O的存在减弱了金属交换剂NaMo(CO)~3(RCp)的交换活性。同时发现加热可加速该反应向产物的转化以及进一步证明了该金属交换反应的普遍性。对合成的簇合物进行了元素分析, 红外和氢的核磁谱的结构表征。对簇合物PhCCo~2(CO)~8(C~2H~5O~2CCp)的单晶进行了X射线结构测定, 该晶体属于单斜晶系, 空间群为P2~1/c, 晶胞参数: α=1.1356(2)nm,b=1.4030(2)nm, c=1.6076(3)nm, β=107.19(1)°, Z=4。D~c=1.80g/cm^3,R=0.048, Rw=0.057。     

四核钴羰基簇合物的合成和晶体结构

用Co₂(CO)₈与有机杂环二硫代次膦酸盐SP(C₆H₄OR)(S)N(C₆H₅)NC(Me)(R=Me,Et)反应,得到两类4个含S,P桥基配体的四核钴羰基簇合物Co₄(CO)₁₀(μ₄-S)[μ₄-P(C₆H₄OR)](1:R=Me;3:R=Et)和Co₄(CO)₁₀(μ₃-S)[μ₂-P(C₆H₄OR)N(C₆H₅)NC(Me)](2:R=Me,4:R=Et).在反应中,前配体中的PS键以及C-S,P-S,P-N键劈开,产生的分子片与金属钴原子配位,组建成新的羰基钴簇.对这4个簇合物进行了元素分析,IR,¹HNMR和MS谱学表征,并测定了簇合物4的晶体结构,该晶体属单斜晶系,P2₁/c空间群,晶胞参数a=1.9065(4)nm,b=1.0081(2)nm,c=1.6663(3)nm,β=97.36(3)°,V=3.1704(11)nm₃,Z=4,D_c=1.743g/cm³.Co1Co3Co4呈三角形分布,其中Co-Co平均键长为0.251nm,而Co₂在该三角平面的一侧,Co2-Co3键为0.269nm.该簇合物分子骨架为三角钉型结构,每个Co原子的立体几何均为变形八面体,但配位环境各不相同.     

庚烯配位的羰基钌氢簇合物H~3Ru~3(CO)~9(C~7H~1~1)的合成及晶体结构

本文合成了庚烯配位的羰基钌氢簇合物H~3Ru~3(CO)~9(C~7H~1~1),用IR, NMR,MS和元素分析等手段对此簇合物进行了结构表征,推测其为含有金属- 氢键的羰基钌簇合物,并且庚烯的双键被打开.X射线衍射测定进一步肯定了上述结论.簇合物为三斜晶系,空间群为PI.晶胞参数:a=0.9726(2)nm,b=0.9868(1)nm,c=1.1104(2)nm,α=103.22(1)°,β=89.89(1)°,γ=91.55(1)°,V=1.0370(3)nm^3,Z=2,μ=21.59cm^-^1,D~0=2.09g/cm^3,F(000)=628,最终偏差因子R=0.0371     

双三苯膦铁硫原子簇配合物(μ-i-C3H7S)(μ-PhCH2S)-Fe2(CO)4(PPh3)2的合成及晶体结构

通过(μ-i-C3H7S)(μ-PhCH2S)Fe2(CO)6和三苯膦在甲苯中回流反应6h, 制得了三苯膦双取代配合物(μ-i-C3H7S)(μ-PhCH2S)Fe2(CO)4(PPh3)2(1), 并用X射线衍射技术测得其单晶结构. 晶体属三斜晶系, 空间群为PI. 晶胞参数: a=10.268(4),b=20.289(1), c=22.799(5)埃; a=94.73(1)°, β=102.98(2)°, γ=89.93(1)°;V=4610.5埃^3, Z=4, Dc=1.36g/cm^3. 晶体结构用直接法(MULTAN 82)测定, 采用块矩阵最小二乘法进行最终结构精化, 最后偏离因子R=0.059, Rw=0.068. 单晶X射线分析表明, 配合物1的簇核是由两个铁原子和两个硫原子组成的蝴蝶式结构; 两个三苯膦配体处于铁-铁弯键的反位; 异丙基和苄基分别以6键与硫相连.     

(μ3-S)FeCo2(CO)7(dppfe)的合成和晶体结构

通过简单取代反应,合成了一个新的混金属簇合物(μ3-S)FeCo2(CO)7(dppfe) (2) (dppfe=Ph2PC5H4FeC5H4PPh2).利用IR,1H NMR,MS 和 X-ray单晶衍射的方法对簇合物2进行了结构表征.簇合物2的晶体属于三斜晶系,空间群为Pī.晶胞参数: a=1.132 4(15) nm, b=1.3670(17) nm, c=1.5769(2) nm,α=114.646(2)°,β=100.340(2)°,γ=100.113(3)°, V=2.0953(5) nm3.     

Synthesis and structural characterization of configurational isomers of tungsten-palladium complexes with bridging diphenyl(dithioalkoxycarbonyl)phosphine as a ligand and phosphine transfer from tungsten to palladium

Treatment of the complex [W(CO)5[PPh2(CS2Me)]] (2) with [Pd(PPh3)4] (1) affords binuclear complexes such as anti-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2Me)PPh2]W(CO)5] (3), syn-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2Me)PPh2]W(CO)5] (4), and trans-[W(CO)4(PPh3)2] (5). In 3 and 4, respectively, the W and Pd atoms are in anti and syn configurations with respect to the P-CS2 bond of the diphenyl(dithiomethoxycarbonyl)phosphine ligand, PPh2(CS2Me). Complex 3 undergoes extensive rearrangement in CHCl3 at room temperature by transfer of a PPh3 ligand from Pd to W, eliminating [W(CO)5(PPh3)] (7), while the PPh2CS2Me ligand transfers from W to Pd to give [[(Ph3P)Pd[mu-eta 1,eta 2-(CS2Me)PPh2]]2] (6). In complex 6, the [Pd(PPh3)] fragments are held together by two bridging PPh2(CS2Me) ligands. Each PPh2(CS2Me) ligand is pi-bonded to one Pd atom through the C=S linkage and sigma-bonded to the other Pd through the phosphorus atom, resulting in a six-membered ring. Treatment of Pd(PPh3)4 with [W(CO)5[PPh2[CS2(CH2)nCN]]] (n = 1, 8a; n = 2, 8b) in CH2Cl2 affords syn-[(Ph3P)2Pd[mu-eta 1,eta 2-[CS2(CH2)nCN]PPh2]W(CO)5] (n = 1, 9a; n = 2, 9b). Similar configurational products syn-[(Ph3P)2Pd[mu-eta 1,eta 2-(CS2R)PPh2]W(CO)5] (R = C2H5, C3H5, C2H4OH, C3H6CN, 11a-d) are synthesized by the reaction of Pd(PPh3)4 with [W(CO)5[PPh2(CS2R)]] (R = C2H5, C3H5, C2H4OH, C3H6CN, 10a-d). Although complexes 11a-d have the same configuration as 9a,b, the SR group is oriented away from Pd in the former and near Pd in the latter. In these complexes, the diphenyl(dithioalkoxycarbonyl)phosphine ligand is bound to the two metals through the C=S pi-bonding and to phosphorus through the sigma-bonding. All of the complexes are identified by spectroscopic methods, and the structures of complexes 3, 6, 9a, and 11d are determined by single-crystal X-ray diffraction. Complexes 3, 9, and 11d crystallize in the triclinic space group P1 with Z = 2, whereas 6 belongs to the monoclinic space group P2/c with Z = 4. The cell dimensions are as follows: for 3, a = 10.920(3) A, b = 14.707(5) A, c = 16.654(5) A, alpha = 99.98(3) degrees, beta = 93.75(3) degrees, gamma = 99.44(3) degrees; for 6, a = 15.106(3) A, b = 9.848(3) A, c = 20.528(4) A, beta = 104.85(2) degrees; for 9a, a = 11.125(3) A, b = 14.089(4) A, c = 17.947(7) A, alpha = 80.13(3) degrees, beta = 80.39(3) degrees, gamma = 89.76(2) degrees; for 11d, a = 11.692(3) A, b = 13.602(9) A, c = 18.471(10) A, alpha = 81.29(5) degrees, beta = 80.88(3) degrees, gamma = 88.82(1) degrees.     

High structural control in metal-mediated synthesis of new functionalized diphosphines using diphosphinoketenimines as precursors

The diphosphinoketenimine ligand in the neutral complexes fac-[MnI(CO)(3){(PPh(2))(2)C=C=NR}] (1 a: R = Ph; 1 b: R = p-tolyl) undergoes nucleophilic attack by MeLi and nBuMgCl yielding, after hydrolysis, the diphosphinoenamine-containing complexes fac-[MnI(CO)(3){(PPh(2))(2)C=C(R')NHR}] (3 a,b: R' = Me; 4 a,b: R' = nBu). Complex 1 a reacts under the same conditions with H(2)C=C=CHMgBr to afford fac-[MnI(CO)(3){(PPh(2))(2)C=C(CH(2)CC[triple chemical bond]CH)NHR}] (5 a), which contains a terminal alkyne group on the alpha-carbon atom of the diphosphinoenamine ligand. The cationic complexes fac-[Mn(CO)(4){(PPh(2))(2)C=C=NR}](+) (6) react with H(2)C=C=CHMgBr to afford diphosphinomethanide derivatives bearing three different types of functional groups, depending upon the substituent on the nitrogen atom of the ketenimine: cumulene in fac-[Mn(CO)(4){(PPh(2))(2)C--C(CH=C=CH(2))=N-xylyl}] (7 d), internal alkyne in fac-[Mn(CO)(4){(PPh(2))(2)C--C(C[triple chemical bond]CCH(3))=NtBu}] (8), and quinoline in 9 (R = Ph), whose formation implies an unusual cyclization process. Protonation of 7 d, 8, and 9 with HBF(4) occurs at the nitrogen atom to give the cationic derivatives 10 d, 11, and 12, respectively, which contain the corresponding functionalized diphosphine ligands. Irradiation of 3 a,b and 4 a,b with Vis/UV light makes it possible to isolate the free ligands (PPh(2))(2)C=C(R')NHR (13 a,b and 14 a,b), completing the metal-assisted synthesis of these novel functionalized diphosphines. Irradiation of 12 with Vis/UV light generates free phosphinoquinoline ligand 15, which readily affords a complex 16 containing 15 as a P,N-chelating ligand when treated with [PdCl(2)(NCMe)(2)], thus demonstrating its coordination capability.     

具有局部松散配位的三核钼簇合物研究:{Mo3(μ3-S)(μ-S)3[S2P(OEt)2]4.P(C6H5)3}.(O86CH2Cl2)的合成和晶体结构

本文报道了具有局部松散配位的三核钼原子簇{Mo3(μ3-S)(μ-S)[S2P(OEt)2]4.P(C6H5)3}.(0.86CH2Cl2)的合成和晶体结构.在CAD-4四圆衍射仪上用Mo Kα射线收集到I≥2σ(I)的衍射点4840个.采用重原子法和差电子密度法解出结构,并用全矩阵最小二乘法修正,最终偏离因子为0.058.簇分子的Mo-Mo键为2.731(1),2.748(1),2.753(1)A,Mo原子和三苯基膦的P原子配位键长为Mo-P2.647(3)A,显著长于一般的Mo-P共价单键.三苯基膦基团在Mo的配位多面体中处于三重桥S原子的对位,表现出与其他此类簇合物的松散配位体配位位置不同.文中概括了此类簇合物的Mo-Mo键和Mo-L的成键情况.     

Subtle reactivity patterns of non-heteroatom-substituted manganese alkynyl carbene complexes in the presence of phosphorus probes

The non-heteroatom-substituted manganese alkynyl carbene complexes (eta5-MeC5H4)(CO)2Mn=C(R)C[triple bond]CR'(3; 3a: R = R'= Ph, 3b: R = Ph, R'= Tol, 3c: R = Tol, R'= Ph) have been synthesised in high yields upon treatment of the corresponding carbyne complexes [eta5-MeC5H4)(CO)2Mn[triple bond]CR][BPh4]([2][BPh4]) with the appropriate alkynyllithium reagents LiC[triple bond]CR' (R'= Ph, Tol). The use of tetraphenylborate as counter anion associated with the cationic carbyne complexes has been decisive. The X-ray structures of (eta5-MeC5H4)(CO)2Mn=C(Tol)C[triple bond]CPh (3c), and its precursor [(eta5-MeC5H4)(CO)2Mn=CTol][BPh4]([2b](BPh4]) are reported. The reactivity of complexes toward phosphines has been investigated. In the presence of PPh3, complexes act as a Michael acceptor to afford the zwitterionic sigma-allenylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R)=C=C(PPh3)R' (5) resulting from nucleophilic attack by the phosphine on the remote alkynyl carbon atom. Complexes 5 exhibit a dynamic process in solution, which has been rationalized in terms of a fast [NMR time-scale] rotation of the allene substituents around the allene axis; metrical features within the X-ray structure of (eta5-MeC5H4)(CO)2MnC(Ph)=C=C(PPh3)Tol (5b) support the proposal. In the presence of PMe3, complexes undergo a nucleophilic attack on the carbene carbon atom to give zwitterionic sigma-propargylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R)(PMe3)C[triple bond]CR' (6). Complexes 6 readily isomerise in solution to give the sigma-allenylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R')=C=C(PMe3)R (7) through a 1,3 shift of the [(eta5-MeC5H4)(CO)2Mn] fragment. The nucleophilic attack of PPh2Me on 3 is not selective and leads to a mixture of the sigma-propargylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R)(PPh(2)Me)C[triple bond]CR' (9) and the sigma-allenylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R)=C=C(PPh(2)Me)R' (10). Like complexes 6, complexes 9 readily isomerize to give the sigma-allenylphosphonium complexes (eta5-MeC5H4)(CO)2MnC(R')=C=C(PPh2Me)R'). Upon gentle heating, complexes 7, and mixtures of 10 and 10' cyclise to give the sigma-dihydrophospholium complexes (eta5-MeC5H4)(CO)2MnC=C(R')PMe2CH2CH(R)(8), and mixtures of complexes (eta5-MeC5H4)(CO)2MnC=C(Ph)PPh2CH2CH(Tol)(11) and (eta5-MeC5H4)(CO)2MnC=C(Tol)PMe2CH2CH(Ph)(11'), respectively. The reactions of complexes 3 with secondary phosphines HPR(1)(2)(R1= Ph, Cy) give a mixture of the eta2-allene complexes (eta5-MeC5H4)(CO)2Mn[eta2-{R(1)(2)PC(R)=C=C(R')H}](12), and the regioisomeric eta4-vinylketene complexes [eta5-MeC5H4)(CO)Mn[eta4-{R(1)(2)PC(R)=CHC(R')=C=O}](13) and (eta5-MeC5H4)(CO)Mn[eta4-{R(1)(2)PC(R')=CHC(R)=C=O}](13'). The solid-state structure of (eta5-MeC5H4)(CO)2Mn[eta2-{Ph2PC(Ph)=C=C(Tol)H}](12b) and (eta5-MeC5H4)(CO)Mn[eta4-{Cy2PC(Ph)=CHC(Ph)=C=O}](13d) are reported. Finally, a mechanism that may account for the formation of the species 12, 13, and 13' is proposed.