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1.
Synthesis of a New Rigid Bicyclic AMPP Ligand (TIAMPP) and Application in Asymmetric Hydrogenation 总被引:2,自引:0,他引:2
Da Chun GONG Ping WEI Hua ZHOU Xiong Liang WANG Ping Kai OUYANG 《中国化学快报》2005,16(9):1169-1172
The new rigid bicyclic AMPP((S)-TIAMPP) has been synthesized from the corresponding Ticol and Ph2PCI. The application of (S)-TIAMPP in Rh-catalyzed asymmetric hydrogenation of α-dehydroamino acids derivatives has been examined. Up to 93% ee was obtained. 相似文献
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A new chiral ligand N‐p‐toluenesulfonyl‐2,2′‐dimethoxy‐6,6′‐diaminobiphenyl (Ts‐DMBDPPA) was prepared from 2,2′‐dimethoxy‐6,6′‐diaminobiphenyl via N‐tosylation. Its Ru(II) complex was effective catalysts for catalytic asymmetric transfer hydrogenation of aromatic ketones (with ee's up to 69.3%). 相似文献
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A new chiral aminophosphine ligand 6,6′-dimethoxy-2,2′-bis(diphenylphosphinoamino)biphenyl(DMBDPPABP) was prepared and its rhodium complex was found to be an effective catalyst for the asymmetric hydrogenation of amidoacrylic acid and its dervatives.The effects of solvent and reaction temperature on enantioselectivity were also studied. 相似文献
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5,5-Diamino BINAP has been synthesized via three steps using BINAPO as starting material with high reaction yield. Present method needed only a stoichiometric quantity of nitric acid in the step of nitration of BINAPO, giving almost quantitative reaction yield. Based on 5,5-diamino BINAP, other three new BINAP derivatives have been synthesized. These modified BINAP ligands showed better catalytic properties as compared to BINAP itself in the asymmetric hydrogenation of 2-(6‘-methoxyl-2‘-naphthyl)acrylic acid. 相似文献
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Chiral diphosphite ligands were prepared by the reaction of (1R,5S,6R)-(trans, trans)-spiro[4.4]nonane-1,6-diol with chlorophosphites. The rhodium(Ⅰ) complexes containing these ligands were tested in the asymmetric hydroformylation of styrene and moderate enantioselectivity (up to 49% ee) was obtained. A pair of diastereomers 5a and 5b gave the opposite configuration of the product, which implies that the sense of enantioface selection is mainly dictated by the configuration of the terminal group on the ligand. 相似文献
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ChengYunWANG ZhiCaiSHANG JiangHuaMEi QingSenYU 《中国化学快报》2003,14(6):579-580
A new chiral multidenate ligand (S,S)-1,7-bis(4-benzyloxazolin-2-yl-methyl)-1,7-diaza-12-crown-4 1 has been synthesized and used as ligand in the copper catalyzed asymmetric cyclopropanation of 1,1-diphenylethylene. 相似文献
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Asymmetric Synthesis and Crystal Structure of (-)-N-[(3R)-3-Cyclohexyl]-3-phenylpropananoyl]bornane-10,2-sultam 总被引:1,自引:1,他引:0
The title compound (-)-N-[(3R)-3-cyclohexyl]-3-phenylpropananoyl]bornane-10,2sultam (C 25 H 35 NO 3 S,M r=429.60),a derivative of camphorsultam,crystallizes in the monoclinic space group P2 1 /c with a=10.3301(7),b=19.4040(13),c=11.8106(8),β=100.5580(10)°,V=2327.3(3) 3,Z=4,D c=1.226 g/cm 3,λ=0.71073,μ(MoKα)=0.165 mm-1 and F(000)=928.X-ray diffraction analysis reveals that the six-membered ring of sultam shows a boat form (Fig.1).The planes constructed by (C(4),C(5),C(6),C(7)) and (C(7),C(8),C(9),C(4)) form a dihedral angle of 69.5°.The C(1)-C(2)-C(3) plane forms dihedral angles to the aforementioned planes of 89.8(1) and 85.9(3)°,respectively.And molecules are linked via hydrogen bonding (C-H···N/O) interactions. 相似文献
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LIU Pei-De PEI Xiao-Ke LIN Bi-Zhou② 《结构化学》2004,23(1):57-61
1INTRODUCTIONThecurrentinterestinoxalatesreflectstheirstructuralrichnessandwideuseinanalyticalche-mistryandindustry[1].BecausemolybdenumintheVandVIoxidationstatesformsaconsiderablenumberofoxocomplexes,andtheequilibriainsolutionbetweenpolyoxomolybdenumspec… 相似文献
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A new coordination polymer [Mn{5-(NO2)sal}2(phen)]n (5-(NO2)sal = 5-nitrosalicylate, phen = 1,10-phenanthroline) was synthesized by a hydrothermal reaction and characterized by elemental analysis, IR and X-ray single-crystal diffraction. The title complex crystallizes in orthorhombic, space group Pbcn with α = 25.747(8), b = 13.220(4), c = 7.009(3) A, V= 2386(1)A^3, Z = 4, R = 0.0427 and wR = 0.0890. The 5-nitrosalicylate anions doubly bridge the Mn(Ⅱ) atoms to form a one-dimensional polymeric chain with repeated eight-membered ring units (Mn-O-C-O)2. The crystal structure is stabilized by intra- and interchain hydrogen bonding interactions. The cyclic voltammetric behavior of the title complex is also reported. 相似文献
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合成了(R,R)-1,2-二苯基乙二胺((R,R)-DPEN)、 钌和三苯基膦的三元配合物RuCl2[P(C6H5)3]2-(R,R)-DPEN, 并将其用于萘乙酮的不对称加氢反应. 考察了碱/催化剂的摩尔比、反应温度和氢气压力等对催化活性和对映选择性的影响. 结果表明,多种因素对反应的转化率和对映选择性均有影响. 在萘乙酮:(CH3)3COK:催化剂摩尔比为 50000:450:1, 氢气压力为4 MPa, 反应温度为25 ℃的条件下,反应16 h时,萘乙酮生成α-萘乙醇的产率和对映选择性分别达到了100%和83%. 相似文献
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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
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The equilibrium structures and relative stabilities of BN-doped fullerenes C70−2x(BN)x (x=1–3) have been studied at the AM1 and MNDO level. The most stable isomers of C70−2x(BN)x have been found out and their electronic properties have been predicted. The calculation results show that the BN substituted fullerenes C70−2x(BN)x have considerable stabilities, though they are less stable than their all carbon analog. For C68BN, the isomers whose BN is located in the most chemically active bonds of C70 (namely B and A) are among the most stable species, of which B is predicted to be the ground state. The stabilities of C68BN decrease and the dipole moments increase with increasing the distance between the heteroatoms. For C66(BN)2, the lowest energy species is the isomer in which the B–N–B–N bond is formed; For C64(BN)3, the most stable species should have three BN units located in the same hexagon to form B–N–B–N–B–N ring. The ionization potentials and the affinity energies of the most stable species of BN-doped C70 are almost the same as those of C70 because of the isoelectronic relationship. The ionization potentials and affinity energies depend on the relative position of the heteroatoms in C68BN, the chemical reactivities of the isomers whose heteroatoms are well separated should differ significantly from their all carbon analog. 相似文献
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Asymmetric transfer hydrogenation of ketones with chiral molecular catalysts is realized to be one of the most magnificent tools to access chiral alcohols in organic synthesis. A new chiral phosphinite compound N,N′-bis[(1S)-1-benzyl-2-O-(diphenylphosphinite)ethyl]ethanediamide (1), has been synthesized by the reaction of chlorodiphenylphosphine with N,N′-bis[(1S)-1-benzyl-2-hydroxyethyl]ethanediamide under argon atmosphere. The oxidation of 1 with aqueous hydrogen peroxide, elemental sulfur or grey selenium in toluene gave the corresponding oxide 1a, sulfide 1b and selenide 1c, respectively. Pd, Pt and Ru complexes were obtained by the reaction of 1 with [MCl2(cod)] (M: Pd 1d, Pt 1e) and [Ru(p-cymene)Cl2]21f, respectively. All these new complexes were characterized by using NMR, FT-IR spectroscopies and microanalysis. Additionally, as a demonstration of their catalytic reactivity, the ruthenium complex 1f was tested as catalyst in the asymmetric transfer hydrogenation reactions of acetophenone derivatives with iPrOH was also investigated. 相似文献
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采用自由配体法将(1S,2S)-DPEN(1,2-diphenyl-1,2-ethylene-diamine)-Ru(TPP)2(TPP=三苯基膦,triphenylphosphine)配合物封装于NaY沸石分子筛超笼中,制备了(1S,2S)-DPEN-Ru(TPP)2/Y主客体材料(1S,2S)-DPEN=1,2-二苯基-1,2-乙二胺).采用等离子体发射光谱ICP、粉末X射线衍射(XRD)、紫外光谱(UV-Vis)、氮吸附等物理化学手段对所制备材料进行了表征.结果表明,(1S,2S)-DPEN-Ru(TPP)2配合物封装于Y型分子筛超笼中保持了原有的物理化学性能;作为苯乙酮不对称加氢催化剂,在优化条件下,苯乙酮的转化率可达100%,(R)-苯乙醇的对映体过量值(ee值)可达61.0%.该催化剂具有良好的稳定性和重复使用性. 相似文献
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不添加任何稳定剂,在碱性条件下制备了5%Ir/SiO2催化剂,并用于催化苯乙酮的不对称加氢反应中,详细考察了碱和手性修饰剂种类、氢气压力、反应温度、(1S,2S)-1,2-二苯基乙二胺((1S,2S)-DPEN)浓度对反应的影响.在优化反应条件下,5%Ir/SiO2催化剂表现出较好的反应活性和对映选择性.其中,苯乙酮不对称加氢反应的对映选择性达70%.该催化剂不需要任何稳定剂,制备方法简单,催化性能稳定,通过简单的离心分离即可循环使用. 相似文献
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在碱性条件下制备了三氧化二铝负载的铱(Ir/γ-Al2O3)催化剂,并用于苯乙酮及其衍生物的不对称催化加氢反应.考察了不同的碱、碱浓度、手性二胺(1S,2S)-1,2-二苯基乙二胺[(1S,2S)-DPEN]浓度、反应温度和反应压力对催化剂及反应的影响.结果显示,在优化反应条件下,该催化剂表现出较高的催化活性和良好的对映选择性,其中异丁酰苯不对称催化加氢反应的对映选择性达到了80.3%.该催化剂不需要使用任何稳定剂,制备方法简单,催化性能稳定,通过简单的离心分离即可循环使用. 相似文献
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[Co(η2-CO3)(NH3)4](NO3)·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O were prepared by prolonged aerial oxidation of a solution of Co(NO3)2·6H2O and ammonium carbonate in aqueous ammonia. The formation of these side products highlights the richness of the chemistry of these systems and the possibility of by products if methods are not strictly adhered to. The X-ray crystal structures of [Co(η2-CO3)(NH3)4][NO3]·0.5H2O and [(NH3)3Co(μ-OH)2(μ-CO3)Co(NH3)3][NO3]2·H2O reveal a monomeric octahedral cobalt center with η2-bound CO32− in the former, while the latter consists of a dimeric array where the two cobalt centers are bridged by two OH− and one μ2-CO32− groups with three terminal NH3 ligands for each Co center. In both complexes extensive hydrogen bonding interactions are evident. 相似文献