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1.
研究了钌-双膦-二胺配合物催化剂RuC1_2[(S)-P-Phos]-[(S)-DAIPEN][P-Phos:2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'.二吡啶,DA肫N:1,1.二(4.甲氧苯基).2.异丙基.1,2.乙二胺]催化芳香酮不对称加氢反应的性能,考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响.在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1,氢气压力为2 MPa,反应温度为30℃时,苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%,2'-溴苯乙醇的ee值町达97.1%.  相似文献   

2.
陶明  熊伟  陈华  李贤均 《分子催化》2007,21(3):260-263
设计合成了一种新型的钌-双膦-手性二胺三元配合物RuC l2(BDPX)[(S,S)-DPEN][BDPX=邻-二(二苯基膦)甲苯,DPEN=1,2-二苯基乙二胺].利用此配合物作催化剂催化了苯乙酮和几种取代苯乙酮的不对称氢化反应;考察了多种因素对苯乙酮不对称氢化反应的转化率和ee值的影响.结果表明,此配合物对苯乙酮进行不对称氢化反应具有良好的催化性能和较高的对映选择性,在优化的条件下,当苯乙酮、配合物的摩尔比为20000?1时,其不对称氢化反应的转化率可达到100%,其ee值可达到59.0%;对取代苯乙酮的不对称氢化反应也具有一定的催化活性和中等的对映选择性.  相似文献   

3.
用邻二苯基膦苯甲醛与不同的手性二胺缩合,高产率地制备了一系列手性双胺双膦配体。这些配体分别与Ru(DMSO)4Cl2或[Rh(COD)Cl]2等反应,可制备相应的手性双胺双膦钌、铑配合物。在异丙醇溶液中,该C2-对称的手性双胺双膦钌、铑配合物是多种芳香酮不对称转移氢化的优化催化剂,反应产物手性芳香醇的转华裔经和对映选择性分别高达99%和98ee。  相似文献   

4.
研究了钌-双膦-二胺配合物催化剂RuCl2[(S)-P-Phos]-[(S)-DAIPEN] [P-Phos: 2,2',6,6'-四甲氧基-4,4'-双(二苯基膦基)-3,3'-二吡啶, DAIPEN: 1,1-二(4-甲氧苯基)-2-异丙基-1,2-乙二胺]催化芳香酮不对称加氢反应的性能, 考察了不同的碱、叔丁醇钾浓度、反应溶剂、底物/催化剂摩尔比等因素对反应活性和对映选择性的影响. 在苯乙酮、叔丁醇钾、催化剂的摩尔比为1000:20:1, 氢气压力为2 MPa, 反应温度为30 ℃时, 苯乙酮的转化率和α-苯乙醇的对映选择性(ee)分别达到了100%和88.5%, 2'-溴苯乙醇的ee 值可达97.1%.  相似文献   

5.
以(1S,2S)-(+)-1,2-二苯基乙二胺为原料,分别与2-噻唑甲醛和4-咪唑甲醛经缩合反应合成了两个新型的四齿手性亚胺配体——N,N'-二(2-噻唑)-1,2-二苯基乙二胺(L1)和N,N'-二(4-咪唑)-1,2-二苯基乙二胺(L2),其结构经1H NMR,IR和ESI-MS表征。L1与Ir Cl(cod)2,L2与[Ir HCl2(cod)]2分别经原位反应制得催化剂CatⅠ和CatⅡ。以异丙醇为氢源,研究了CatⅠ和CatⅡ对苯乙酮经不对称氢转移反应合成手性α-苯乙醇的催化性能。结果表明:在最佳反应条件[苯乙酮0.5 mmol,n(KOH)∶n(Cat)=4∶1,异丙醇15 m L,于45℃反应10 h]下,CatⅠ为催化剂时,转化率90%,ee值33%;CatⅡ为催化剂时,转化率87%,ee值27%。  相似文献   

6.
本文合成了N,N'-双(2'-羟基苯乙酮)缩乙二胺、N,N'-双(2'-羟基苯乙酮)缩1,2-丙二胺、N,N'-双(2'-羟基苯乙酮)缩1,3-丙二胺和N,N'-双(2'-羟基苯乙酮)缩邻苯二胺四种Schiff配体以及它们的锰(Ⅲ)配合物1,2,3和4.并考察了这四种锰(Ⅲ)配合物作为催化剂,催化以NaOCl为氧源环氧化苯乙烯和环己烯的反应的性能.同对考察了反应温度、助配体、NaOCl的浓度以及pH值对催化环氧化反应的影响.  相似文献   

7.
以双齿P,N-配体8-(二苯基膦基)喹啉(DPPQ)为支撑配体的钌亚丙二烯基配合物[RuCl(=C=C=CR_2)(DPPQ)_2]-[BPh_4](3a:R=苯基;3b:CR_2=FN=亚芴基)可由双核钌配合物[Ru(μ-Cl)(DPPQ)_2]_2[BPh_4]_2(1)分别与过量的1,1-二苯基炔丙醇(2a)或9-乙炔-9-芴醇(2b)反应得到.配合物3易与肼在室温下反应生成丙烯腈的钌配合物[RuCl(N≡C—CH=CR)2)(DPPQ))2][BPh)4](4a:R=苯基;4b:CR)2=FN=亚芴基),该反应涉及肼对亚丙二烯基配体α-碳原子的分子间亲核进攻,是首例肼对金属亚丙二烯基加成生成丙烯腈的反应.配合物4与过量的丙炔醇2反应可释放出3,3-二苯基丙烯腈(5a)或3-芴基丙烯腈(5b),并再生亚丙二烯基配合物3.此外,初步考察了配合物1对端基炔丙醇与肼反应生成丙烯腈的催化活性,结果表明该催化反应的确可以进行,但是得到的丙烯腈产物的产率不高.尽管结果不是很理想,但是这些研究表明可望发展端基炔丙醇与肼经由过渡金属亚丙二烯基中间体转化为丙烯腈的新催化反应.  相似文献   

8.
熊伟  杨朝芬  袁茂林  陈华  李贤均 《催化学报》2005,26(12):1093-1098
 将手性二胺(1S,2S)-1,2-二苯基乙二胺二磺酸钠((1S,2S)-DPENDS)修饰的钌膦配合物用于催化水/有机两相体系中苯乙酮的不对称加氢. 结果表明, (1S,2S)-DPENDS和KOH的浓度对反应有很大影响,二者的协同作用使配合物的催化活性和产物的对映选择性大大提高. 对温度、压力、底物/钌的摩尔比和膦配体/钌摩尔比等反应条件进行优化后,以[RuCl2-(TPPTS)2]2为催化剂前体催化苯乙酮不对称加氢时,产物的ee值可达66.4%, 催化剂经过简单的相分离即可循环使用.  相似文献   

9.
研究了用手性修饰剂(1S,2S)-(-)-1,2-二苯基乙二胺修饰的负载型钌催化剂(Ru/γ-Al2O3)催化芳香酮的不对称加氢反应,在KOH的异丙醇溶液中,10~20℃,pH2=5 MPa条件下,芳香酮及其衍生物加氢产物的ee值达79.5%~85.0%,2-乙酰基噻吩加氢产物的ee值可达86.2%.此催化剂制备简单,容易与产物分离,重复使用4次,对映选择性基本保持不变.  相似文献   

10.
钌可以促使炔烃通过亚乙烯基钌卡宾金属配合物或钌金属杂环配合物的形式发生碳-碳偶联反应,它的化学性质很大程度上取决于配体的电子和立体特征.普通环戊二烯基钌配合物可以促使炔烃三聚生成苯环衍生物或使两分子炔烃和一分子含C=X键(X=C,O,S,N等)的不饱和底物发生环加成反应得到杂环化合物.含桥联碳硼烷-环戊二烯基配体的钌乙腈配合物[η5:σ-Me2C(C5H4)(C2B10H10)]Ru(NCCH3)2(1)表现出与环戊二烯基钌不同的反应性质.例如,配合物1与三甲基硅基取代的端炔或中间炔反应可生成含有单或双亚乙烯基有机钌卡宾配合物;与末端芳炔则通过三分子炔和桥联配体中的环戊二烯基发生加成反应得到含有独特三环结构的有机钌配合物.以上结果表明,配体的位阻效应和炔烃的种类都可以影响产物的类型.本文进一步研究了此钌乙腈配合物1与烷基或芳基取代的中间炔及中间二炔的反应.配合物1与3-己炔或二苯乙炔在甲苯中于80℃反应可以生成对空气和水稳定的η4-钌-环丁二烯配合物[η5:σ-Me2C(C5H4)(C2B10H10)]Ru(η4-C4Et4)(2)或[η5:σ-Me2C(C5H4)(C2B10H10)]Ru(η4-C4Ph4...  相似文献   

11.
Neutral and cationic mononuclear complexes containing both group 15 and polypyridyl ligands [Ru(kappa3-tptz)(PPh3)Cl2] [1; tptz=2,4,6-tris(2-pyridyl)-1,3,5-triazine], [Ru(kappa3-tptz)(kappa2-dppm)Cl]BF4 [2; dppm=bis(diphenylphosphino)methane], [Ru(kappa3-tptz)(PPh3)(pa)]Cl (3; pa=phenylalanine), [Ru(kappa3-tptz)(PPh3)(dtc)]Cl (4; dtc=diethyldithiocarbamate), [Ru(kappa3-tptz)(PPh3)(SCN)2] (5) and [Ru(kappa3-tptz)(PPh3)(N3)2] (6) have been synthesized. Complex 1 has been used as a metalloligand in the synthesis of homo- and heterodinuclear complexes [Cl2(PPh3)Ru(micro-tptz)Ru(eta6-C6H6)Cl]BF4 (7), [Cl2(PPh3)Ru(mu-tptz)Ru(eta6-C10H14)Cl]PF6 (8), and [Cl2(PPh3)Ru(micro-tptz)Rh(eta5-C5Me5)Cl]BF4 (9). Complexes 7-9 present examples of homo- and heterodinuclear complexes in which a typical organometallic moiety [(eta6-C6H6)RuCl]+, [(eta6-C10H14)RuCl]+, or [(eta5-C5Me5)RhCl]+ is bonded to a ruthenium(II) polypyridine moiety. The complexes have been fully characterized by elemental analyses, fast-atom-bombardment mass spectroscopy, NMR (1H and 31P), and electronic spectral studies. Molecular structures of 1-3, 8, and 9 have been determined by single-crystal X-ray diffraction analyses. Complex 1 functions as a good precursor in the synthesis of other ruthenium(II) complexes and as a metalloligand. All of the complexes under study exhibit inhibitory effects on the Topoisomerase II-DNA activity of filarial parasite Setaria cervi and beta-hematin/hemozoin formation in the presence of Plasmodium yoelii lysate.  相似文献   

12.
Polydentate ligands, N,N'-bis[o-(diphenylphosphino)benzylidene]-1,2-propane-diamine [P2N2Me for short] and N,N'-bis[o-(diphenylphosphino)benzy1]-1,2-propanediamine [P2N2 H4Me for short] have been synthesized. The interaction of RuCl2(DMSO)4 with one equivalent of P2N2Me or P2N2H4Me in refluxing toluene gave trans-RuCl2(P2N2Me) and trans-RuCl2(P2N4H4Me) in good yield, respectively. The ligands and the complexes have been fully characterized by elemental analysis and spectroscopic methods. The complexes act as an excellent catalyst precursor in hydrogen transfer hydrogenation of acetophenone in catalyst: acetophenone :iso-PrOK of 1: 100: 15, leading to 2-phenylethanol of 89-96% yield.  相似文献   

13.
Reaction of the ruthenium half sandwich compound RuCl(eta(5)-C(5)H(5))(PPh(3))(2) with the uracil (Ur) substituted alkyne HC[triple bond, length as m-dash]CUr in the presence of halide scavengers NH(4)X (X = PF(6), BF(4), OTf) results in the formation of the vinylidene complexes [Ru([double bond, length as m-dash]C[double bond, length as m-dash]CHUr)(eta(5)-C(5)H(5))(PPh(3))(2)][X] which crystallize in the hexagonal space group P6(3)/m. The hexagonal symmetry inherent to the system is due to the formation of a hydrogen bonded array mediated by the two sets of donor-acceptor units on the uracil, resulting in the formation of a cyclic "rosette" containing six ruthenium cations. In solution the (1)H and (31)P{(1)H} NMR spectra of the vinylidene complexes are both concentration and temperature dependent, in accord with the presence of monomer-dimer equilibria in which the rate of rotation of the vinylidene group is fast on the NMR timescale in the monomeric species, but slow in the dimers. The isoelectronic molybdenum-containing vinylidene complex [Mo(eta(7)-C(7)H(7))(dppe)([double bond, length as m-dash]C[double bond, length as m-dash]CHUr)][BF(4)] (dppe = 1,2-bis(diphenylphosphino)ethane) has also been prepared, but forms symmetric dimers in the solid state.  相似文献   

14.
Four stanna-closo-dodecaborate complexes of ruthenium have been prepared and characterized by multinuclear NMR studies in solution and in the solid state. The solid-state structures of the dimeric zwitterions [[Ru(dppb)(SnB11H11)]2] (2) (dppb = bis(diphenylphosphino)butane), [[Ru(PPh3)2(SnB11H11)]2] (3), and the dianionic ruthenium complex [Bu3MeN]2[Ru(dppb)[2,7,8-(mu-H)3-exo-SnB11H11](SnB11H11)] (4) were determined by X-ray crystal structure analysis; they establish an unprecedented structural motif in the chemistry of heteroboranes and transition-metal fragments with the stanna-closo-dodecaborate moiety as a two-faced ligand that exhibits eta1(Sn) as well as eta3(B-H) coordination. The eta3-coordinated stannaborate in 4 and in the isostructural compound [Bu3MeN]2[Ru(PPh3)2[2,7,8-(mu-H)3-exo-SnB11H11](SnB11H11)] (5) shows fluxional behavior, which was studied in detail by using 31P[1H] EXSY and DNMR experiments. The activation parameters for the dynamic process of 5 are given.  相似文献   

15.
Treatment of cis-[W(N2)2(PMe2Ph)4] (5) with an equilibrium mixture of trans-[RuCl(eta 2-H2)(dppp)2]X (3) with pKa = 4.4 and [RuCl(dppp)2]X (4) [X = PF6, BF4, or OTf; dppp = 1,3-bis(diphenylphosphino)propane] containing 10 equiv of the Ru atom based on tungsten in benzene-dichloroethane at 55 degrees C for 24 h under 1 atm of H2 gave NH3 in 45-55% total yields based on tungsten, together with the formation of trans-[RuHCl(dppp)2] (6). Free NH3 in 9-16% yields was observed in the reaction mixture, and further NH3 in 36-45% yields was released after base distillation. Detailed studies on the reaction of 5 with numerous Ru(eta 2-H2) complexes showed that the yield of NH3 produced critically depended upon the pKa value of the employed Ru(eta 2-H2) complexes. When 5 was treated with 10 equiv of trans-[RuCl(eta 2-H2)(dppe)2]X (8) with pKa = 6.0 [X = PF6, BF4, or OTf; dppe = 1,2-bis(diphenylphosphino)ethane] under 1 atm of H2, NH3 was formed in higher yields (up to 79% total yield) compared with the reaction with an equilibrium mixture of 3 and 4. If the pKa value of a Ru(eta 2-H2) complex was increased up to about 10, the yield of NH3 was remarkably decreased. In these reactions, heterolytic cleavage of H2 seems to occur at the Ru center via nucleophilic attack of the coordinated N2 on the coordinated H2 where a proton (H+) is used for the protonation of the coordinated N2 and a hydride (H-) remains at the Ru atom. Treatment of 5, trans-[W(N2)2(PMePh2)4] (14), or trans-[M(N2)2(dppe)2] [M = Mo (1), W (2)] with Ru(eta 2-H2) complexes at room temperature led to isolation of intermediate hydrazido(2-) complexes such as trans-[W(OTf)(NNH2)(PMe2Ph)4]OTf (19), trans-[W(OTf)(NNH2)(PMePh2)4]OTf (20), and trans-[WX(NNH2)(dppe)2]+ [X = OTf (15), F (16)]. The molecular structure of 19 was determined by X-ray analysis. Further ruthenium-assisted protonation of hydrazido(2-) intermediates such as 19 with H2 at 55 degrees C was considered to result in the formation of NH3, concurrent with the generation of W(VI) species. All of the electrons required for the reduction of N2 are provided by the zerovalent tungsten.  相似文献   

16.
The reaction of the silver complexes [((Ru(CO)2(eta-C5H4R))2(mu-C identical to C))3Ag3][BF4]3 (R = H or Me) with [RuCl(CO)2(eta-C5H4R)] at room temperature gave the new trimetallic complexes [(Ru(CO)2(eta-C5H4R))3(eta 1:eta 2-C identical to C))][BF4] which contain the C2(2-) ligand surrounded by ruthenium atoms; these complexes do not contain metal-metal bonds and were characterised by single crystal X-ray studies; the solid state structure is not retained in solution, where it is found to be fluxional on the NMR timescale and the dynamic process postulated could be described as 'bearing-like'.  相似文献   

17.
Reaction of cis-[RuCl2(dppm)2] (dppm = bis(diphenylphosphino)methane) with CS2 and NaOH yields the first ruthenium dithiocarbonate complex, [Ru(kappa2-S2C=O)(dppm)2]. Protonation with tetrafluoroboric acid affords the xanthate complex [Ru(kappa2-S2COH)(dppm)2]BF4 in a reversible manner, suggesting that this may be an intermediate in dithiocarbonate formation. [Ru(kappa2-S2C=O)(dppm)2] reacts with methyl iodide or [Me3O]BF4 to give [Ru(kappa2-S2COMe)(dppm)2]+, also obtained from the reaction of cis-[RuCl2dppm)2] with CS2 and NaOMe. Two modifications of [Ru(kappa2-S(2)C=O)(dppm)2] were examined crystallographically and the structure of [Ru(kappa2-S2COMe)(dppm)2]BF4 and a new modification of cis-[RuCl2(dppm)2] are also reported.  相似文献   

18.
A series of new dicationic dihydrogen complexes of ruthenium of the type cis-[(dppm)(2)Ru(eta(2)-H(2))(L)][BF(4)](2) (dppm = Ph(2)PCH(2)PPh(2); L = P(OMe)(3), P(OEt)(3), PF(O(i)Pr)(2)) have been prepared by protonating the precursor hydride complexes cis-[(dppm)(2)Ru(H)(L)][BF(4)] (L = P(OMe)(3), P(OEt)(3), P(O(i)Pr)(3)) using HBF(4).Et(2)O. The cis-[(dppm)(2)Ru(H)(L)][BF(4)] complexes were obtained from the trans hydrides via an isomerization reaction that is acid-accelerated. This isomerization reaction gives mixtures of cis and trans hydride complexes, the ratios of which depend on the cone angles of the phosphite ligands: the greater the cone angle, the greater is the amount of the cis isomer. The eta(2)-H(2) ligand in the dihydrogen complexes is labile, and the loss of H(2) was found to be reversible. The protonation reactions of the starting hydrides with trans PMe(3) or PMe(2)Ph yield mixtures of the cis and the trans hydride complexes; further addition of the acid, however, give trans-[(dppm)(2)Ru(BF(4))Cl]. The roles of the bite angles of the dppm ligand as well as the steric and the electronic properties of the monodentate phosphorus ligands in this series of complexes are discussed. X-ray crystal structures of trans-[(dppm)(2)Ru(H)(P(OMe)(3))][BF(4)], cis-[(dppm)(2)Ru(H)(P(OMe)(3))][BF(4)], and cis-[(dppm)(2)Ru(H)(P(O(i)Pr)(3))][BF(4)] complexes have been determined.  相似文献   

19.
The methylhydrazine complex [Ru(NH(2)NHMe)(PyP)(2)]Cl(BPh(4)) (PyP=1-[2-(diphenylphosphino)ethyl]pyrazole) was synthesised by addition of methylhydrazine to the bimetallic complex [Ru(mu-Cl)(PyP)(2)](2)(BPh(4))(2). The methylhydrazine ligand of the ruthenium complex has two different binding modes: side-on (eta(2)-) when the complex is in the solid state and end-on (eta(1)-) when the complex is in solution. The solid-state structure of [Ru(PyP)(2)(NH(2)NHMe)]Cl(BPh(4)) was determined by X-ray crystallography. 2D NMR spectroscopic experiments with (15)N at natural abundance confirmed that in solution the methylhydrazine is bound to the metal centre by only the -NH(2) group and the ruthenium complex retains an octahedral conformation. Hydrazine complexes [RuCl(PyP)(2)(eta(1)-NH(2)NRR')]OSO(2)CF(3) (in which R=H, R'=Ph, R=R'=Me and NRR'=NC(5)H(10)) were formed in situ by the addition of phenylhydrazine, 1,1-dimethylhydrazine and N-aminopiperidine, respectively, to a solution of the bimetallic complex [Ru(mu-Cl)(PyP)(2)](2)(OSO(2)CF(3))(2) in dichloromethane. These substituted hydrazine complexes of ruthenium were shown to exist in an equilibrium mixture with the bimetallic starting material.  相似文献   

20.
Intramolecular [2 + 2] cycloaddition of two C=C bonds in vinylidene complexes [Ru(eta5-C9H7){=C=C(R)H}(PPh3){kappa1-(P)-PPh2(C3H5)][BF4] affords cyclobutylidene complexes [Ru(eta5-C9H7){kappa2-(P,C)-(=CC(R)HCH2CHCH2PPh2)}(PPh3)][BF4], which can be also obtained by reaction of terminal alkynes with [Ru(eta5-C9H7)(PPh3){kappa3-(P,C,C)-PPh2(C3H5)}][PF6]. The reaction proceeds under mild conditions via vinylidene complexes, and the activation parameters were determined by kinetic studies.  相似文献   

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