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BF_3·Et_2O promoted conjugate addition of ethanethiol to electron-deficient alkynes 被引量:1
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作者 Qing Fa Zhou Xue Ping Chu Shen Zhao Tao Lu Wei Fang Tang 《Chinese Chemical Letters》 SCIE CAS CSCD 2012年第6期639-642,共4页
An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by BF3.Et20 has been developed. Electron-deficient internal alkynes react ... An effective method for the synthesis of vinyl thioethers through the conjugate addition of ethanethiol to electron-deficient alkynes promoted by BF3.Et20 has been developed. Electron-deficient internal alkynes react with ethanethiol in this system to yield mainly Z-isomer of vinyl thioether adducts, while electron-deficient terminal alkynes afford mainly E-isomer of vinyl thioether adducts. 展开更多
关键词 Vinyl thioether electron-deficient alkyne Conjugate addition SYNTHESIS
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Molecular diversity of triphenylphosphine promoted reaction of electron-deficient alkynes and arylidene Meldrum acid(N,N’-dimethylbarbituric acid)
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作者 Ying Han Hui Zheng +1 位作者 Yuan-Yuan Zhang Chao-Guo Yan 《Chinese Chemical Letters》 SCIE CAS CSCD 2020年第5期1337-1341,共5页
The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazas... The three-component reaction of triphenylphosphine,dimethyl hex-2-en-4-ynedioate and arylidene N,N’-dimethylbarbituric acids in dry methylene dichloride at room temperature afforded trans-1,3-disubstituted 7,9-diazaspiro[4.5]dec-1-enes in good yields and with high diastereoselectivity.However,the similar three-component reaction with arylidene Meldrum acids resulted in a mixtures of cis/trans-1,2-disubstituted 7,9-dioxaspiro[4.5]dec-1-enes.Additionally,the three-component reaction of triphenylphosphine,dimethyl but-2-ynedioate and arylidene Meldrum acids gave polysubstituted 5-(triphe nyl-λ~5-phosphanylidene)cyclopenta-1,3-die nes.A plausible reaction mechanism was proposed for the formation of various products with different regioselectivity and diastereoselectivity. 展开更多
关键词 PHOSPHINE electron-deficient alkyne Meldrum acid Barbituric acid Spiro compound
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Rhodium(Ⅲ)-catalyzed [3+2] annulative coupling between oximes and electron-deficient alkynes
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作者 Xukai Zhou Songjie Yu +1 位作者 Zisong Qi Xingwei Li 《Science China Chemistry》 SCIE EI CAS CSCD 2015年第8期1297-1301,共5页
Rhodium(III)-catalyzed coupling between ketoximes and alkynes via C–H activation and annulation typically followed the[4+2]selectivity to afford isoquinolines.By designing alkynes bearing a highly electron-withdrawin... Rhodium(III)-catalyzed coupling between ketoximes and alkynes via C–H activation and annulation typically followed the[4+2]selectivity to afford isoquinolines.By designing alkynes bearing a highly electron-withdrawing group and under substrate control,we have successfully switched the selectivity of the coupling between oximes and alkynes to the alternative[3+2]annulation,leading to the efficient synthesis of indenamines.This process features good regioselectivity for both substrates,high efficiency,broad substrate scope,and excellent functional group tolerance. 展开更多
关键词 rhodium(III) C-H activation ANNULATION OXIME alkyne
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Electron-deficient Cu site catalyzed acetylene hydrochlorination 被引量:3
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作者 Bolin Wang Chunxiao Jin +7 位作者 Shujuan Shao Yuxue Yue Yuteng Zhang Saisai Wang Renqin Chang Haifeng Zhang Jia Zhao Xiaonian Li 《Green Energy & Environment》 SCIE EI CAS CSCD 2023年第4期1128-1140,共13页
Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by con... Rational design of catalytic sites to activate the C≡C bond is of paramount importance to advance acetylene hydrochlorination. Herein, Cu sites with electron-rich and electron-deficient states were constructed by controlling the impregnation solutions. The π electrons flowing from acetylene to Cu site are facilitated over the electron-deficient Cu sites, achieving high activation of C≡C bond. The contradiction between the increased activation of acetylene required for enhanced catalytic activity and the resistance of Cu site to reduction by acetylene required for maintaining catalytic stability can be balanced by establishing strong interactions of Cu site with pyrrolic-N species. The catalytic activity displays a volcano shape scaling relationship as a function of Cu particle size. Tribasic copper chloride is concomitantly generated with the construction of electron-deficient Cu sites. The H–Cl bond of HCl can be activated over the tribasic copper chloride, accelerating the surface reaction of vinyl chloride production. This strategy of inducing electron deficiency provides new insight into the rational design of catalysts for the synthesis of vinyl chloride with a high catalytic performance. 展开更多
关键词 C≡C bond Acetylene hydrochlorination Cu sites Tribasic copper chloride electron-deficient
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Superior aggregation, morphology and photovoltaic performance enabled by fine tuning of fused electron-deficient units in polymer donors
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作者 Mingrui Pu Xue Lai +5 位作者 Hui Chen Congcong Cao Zixiang Wei Yulin Zhu Leilei Tian Feng He 《Journal of Energy Chemistry》 SCIE EI CAS CSCD 2023年第2期19-26,I0002,共9页
Copolymerization of an electron-rich donor(D)unit with an electron-deficient acceptor(A)unit to construct efficient D-π-A-πtype donors is an effective strategy for organic solar cell applications.The electron-defici... Copolymerization of an electron-rich donor(D)unit with an electron-deficient acceptor(A)unit to construct efficient D-π-A-πtype donors is an effective strategy for organic solar cell applications.The electron-deficient unit fusion,endows extendedπ-conjugation plane and insures excellent photoelectronic property,has great advantages to build A moiety and gradually receives considerable attention.In this work,we adopt benzo[2,1-b:3,4-b’]dithiophene and benzopyrazine(BP),benzothiadiazole(BT)and benzoselenadiazole(BS)to cleverly construct a series of fused A units with different electrondeficient ability,and further synthesize three polymer donors PBDP-BP,PBDP-BT,and PBDP-BS,respectively.The relationships between structure and performance were systematically investigated.PBDPBT shows a moderate aggregation behavior in both solution and film,and the highest hole mobility among the three polymers.After blending with Y6,the PBDP-BT:Y6-based film has the strongest absorption,favorable compatibility,superior crystallinity,and uniform phase separation morphology compared with PBDP-BP or PBDP-BS based blend films.Thus,the device based on PBDP-BT:Y6 has the highest and balanced charge mobility,suppressive recombination,reduced energy loss and achieves an outstanding PCE of 15.14%,which is superior to PBDP-BP:Y6(8.55%)and PBDP-BS:Y6(6.85%).These results provide learnable guidelines for future fused electron-deficient unit-based donor design for photovoltaic application. 展开更多
关键词 Polymer donor electron-deficient Aggregation behavior MORPHOLOGY Organic solar cell
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Catalytic nucleophilic addition of terminal alkynes to α,β-unsaturated-γ-lactams
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作者 王茂荣 高宝 黄汉民 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第4期476-483,共8页
A novel catalytic reaction has been developed for the nucleophilic addition of terminal alkynes toα,β‐unsaturated‐γ‐lactams via a cyclic N‐acyliminium ion intermediate. This simple reaction pro‐ceeds rapidly u... A novel catalytic reaction has been developed for the nucleophilic addition of terminal alkynes toα,β‐unsaturated‐γ‐lactams via a cyclic N‐acyliminium ion intermediate. This simple reaction pro‐ceeds rapidly under mild conditions, and provided a practical approach for the synthesis of a wide range of 5‐alkynyl‐2‐pyrrolidinones in moderate to good yields (45%–76%). 展开更多
关键词 Carbon-hydrogen addition Bronsted acid N-Acyliminium ion Terminal alkyne Pyrrolidin-2-one
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Cu(I)/Diamine-catalyzed Aryl-alkyne Coupling Reactions 被引量:1
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作者 Ye Feng WANG Wei DENG +1 位作者 Lei LIU Qing Xiang GUO 《Chinese Chemical Letters》 SCIE CAS CSCD 2005年第9期1197-1200,共4页
CuI/ethylene diamine/K2CO3/dioxane is shown to be a useful system for the cross coupling reactions of various aryl iodides and bromides with aryl and alkyl alkynes. Compared to the conventional Sonogashira reactions, ... CuI/ethylene diamine/K2CO3/dioxane is shown to be a useful system for the cross coupling reactions of various aryl iodides and bromides with aryl and alkyl alkynes. Compared to the conventional Sonogashira reactions, the new procedure is free of palladium and phosphines. 展开更多
关键词 Sonogashira coupling reaction CUI aryl halide alkyne DIAMINE
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Tri(t-butyl)phosphine-assisted selective hydrosilylation of terminal alkynes 被引量:1
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作者 Wu, Wei Zhang, Xiao Yun +1 位作者 Kang, Shou Xing Gao, Yan Min 《Chinese Chemical Letters》 SCIE CAS CSCD 2010年第3期312-316,共5页
A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were ob... A highly efficient and regio-/stereoselective method of hydrosilylating terminal alkynes was developed using Pt(DVDS)-tri(t-butyl) phosphine catalyst system at room temperature.Trans-products or alpha-products were obtained almost exclusively depending on the alkynes and silanes employed. 展开更多
关键词 HYDROSILYLATION Terminal alkynes Tri(t-butyl)phosphine PLATINUM
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Visible light promoted difunctionalization reactions of alkynes 被引量:3
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作者 Xiang Ren Zhan Lu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第7期1003-1019,共17页
Visible light promoted difunctionalization of alkynes is reviewed. The difunctionalization reaction is achieved by different reagents. Radicals such as carbon(sp3), carbon(sp2), and other heteroatom(P, S, N, Se, O, an... Visible light promoted difunctionalization of alkynes is reviewed. The difunctionalization reaction is achieved by different reagents. Radicals such as carbon(sp3), carbon(sp2), and other heteroatom(P, S, N, Se, O, and halide) radicals initiated by visible light can undergo radical addition to a carbon-carbon triple bond. Upon further transformation, the desired difunctionalized products are obtained. Some organometallic complexes can be activated by visible light;the difunctionalization of alkynes is catalyzed by these species. Other reagents like 1,3-dipole precursors could also react with alkynes to give difunctionalization products;here, the 1,3-dipole derivatives are obtained by visible light photocatalysis. So far, the strategy has been succeeded in the formation of C–C bonds and C–X bonds. Several valuable chemical skeletons have been constructed under mild conditions. However, high regio-and stereoselectivities in some direct difunctionalization methodologies are yet to be achieved. 展开更多
关键词 Visible light photocatalysis Difunctionalization CYCLIZATION alkyne Redox catalyst
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Selectivity control in alkyne semihydrogenation:Recent experimental and theoretical progress 被引量:3
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作者 Xiao-Tian Li Lin Chen +1 位作者 Cheng Shang Zhi-Pan Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第8期1991-2000,共10页
Researchers have been attempting to characterize heterogeneous catalysts in situ in addition to correlating their structures with their activity and selectivity in spite of many challenges.Here,we review recent experi... Researchers have been attempting to characterize heterogeneous catalysts in situ in addition to correlating their structures with their activity and selectivity in spite of many challenges.Here,we review recent experimental and theoretical advances regarding alkyne selective hydrogenation by Pd‐based catalysts,which are an important petrochemical reaction.The catalytic selectivity for the reaction of alkynes to alkenes is influenced by the composition and structure of the catalysts.Recent progress achieved through experimental studies and atomic simulations has provided useful insights into the origins of the selectivity.The important role of the subsurface species(H and C)was revealed by monitoring the catalyst surface and the related catalytic performance.The atomic structures of the Pd catalytic centers and their relationship with selectivity were established through atomic simulations.The combined knowledge gained from experimental and theoretical studies provides a fundamental understanding of catalytic mechanisms and reveals a path toward improved catalyst design. 展开更多
关键词 alkyne semihydrogenation Catalytic selectivity Surface science Machine learning Neural network potential
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Highly active binuclear Cu(Ⅱ) catalyst bearing an unsymmetrical bipyridine-pyrazole-amine ligand for the azide-alkyne cycloaddition reaction 被引量:2
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作者 Baofeng Han Xiao Xiao +2 位作者 Lan Wang Wenjing Ye Xiaoping Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2016年第9期1446-1450,共5页
Ligands containing NH groups often show special characteristics.In this paper,a well-defined dinuclear Cu(II) complex bearing an unsymmetrical bipyridine-pyrazole-amine ligand was synthesized by the condensation of ... Ligands containing NH groups often show special characteristics.In this paper,a well-defined dinuclear Cu(II) complex bearing an unsymmetrical bipyridine-pyrazole-amine ligand was synthesized by the condensation of N–H to release H2O.Using sodium L-ascorbate as a reductant,the binuclear complex showed excellent activity in 1,3-dipolar cycloaddition reactions between alkynes and azides to obtain 1,4-disubstituted triazoles in 95%–99% isolated yields. 展开更多
关键词 N-heterocycle ligand Cu complex 1 3-Dipolar cycloaddition alkynes AZIDES
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Unveiling subsurface hydrogen inhibition for promoting electrochemical transfer semihydrogenation of alkynes with water 被引量:1
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作者 Qi Hao Yongmeng Wu +2 位作者 Cuibo Liu Yanmei Shi Bin Zhang 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2022年第12期3095-3100,共6页
Highly selective electrocatalytic semihydrogenation of alkynes to alkenes with water as the hydrogen source over palladium-based electrocatalysts is significant but remains a great challenge because of the excessive h... Highly selective electrocatalytic semihydrogenation of alkynes to alkenes with water as the hydrogen source over palladium-based electrocatalysts is significant but remains a great challenge because of the excessive hydrogenation capacity of palladium.Here,we propose that an ideal palladium catalyst should possess weak alkene adsorption and inhibit subsurface hydrogen formation to stimulate the high selectivity of alkyne semihydrogenation.Therefore,sulfur-modified Pd nanowires(Pd-S NWs)are designedly prepared by a solid-solution interface sulfuration method with KSCN as the sulfur source.The introduction of S weakens the alkene adsorption and prevents the diffusion of active hydrogen(H^(*))into the Pd lattice to form unfavorable subsurface H^(*).As a result,electrocatalytic alkyne semihydrogenation is achieved over a Pd-S NWs cathode with wide substrate scopes,potential-independent up to 99%alkene selectivity,good fragile groups compatibility,and easily synthesized deuterated alkenes.An adsorbed hydrogen addition mechanism of this semihydrogenation reaction is proposed.Importantly,an easy modification of commercial Pd/C by in situ addition of SCN–enabling the gram-scale synthesis of an alkene with 99%selectivity and 95%conversion highlights the promising potential of our method. 展开更多
关键词 ELECTROCATALYSIS alkyne semihydrogenation Selectivity Hydrogen adsorption Interface sulfuration
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On the comparable activity in plasmonic photocatalytic and thermocatalytic oxidative homocoupling of alkynes over prereduced copper ferrite 被引量:1
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作者 Ying Zhu Nan Deng +1 位作者 Meiqing Feng Peng Liu 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 北大核心 2019年第10期1505-1515,共11页
Despite of extensive attention on the copper-based heterogeneous oxidative homocoupling of alkynes(OHA)to 1,3-diynes,the photocatalytic OHA is scarcely investigated.By screening copper-containing spinel catalysts,we d... Despite of extensive attention on the copper-based heterogeneous oxidative homocoupling of alkynes(OHA)to 1,3-diynes,the photocatalytic OHA is scarcely investigated.By screening copper-containing spinel catalysts,we discovered that a prereduced copper ferrite(CuFe2O4)not only can catalyze the thermocatalytic OHA but also is efficient for the photocatalytic OHA under visible light irradiation.It is found that the sol-gel combustion(SG)method and the partial reduction at 250 ℃ can result in the optimal CuFe2O4-SG-250 catalyst showing high activity and stability.Surface oxidized Cu2O is evidenced to be the active species for the thermocatalytic OHA,whereas metallic copper nanopaticles(CuNPs)are identified as the active sites for the photocatalytic OHA.The efficiency of photocatalytic OHA at ambient temperature is comparable to that of thermocatalytic OHA at 120 ℃,and the CuFe2O4-SG-250 catalyst can be magnetically separated and reused at least five times.The localized surface plasmon resonance effect of CuNPs contributes to visible light-induced photocatalytic OHA. 展开更多
关键词 alkyne HOMOCOUPLING Copper ferrite Copper nanoparticles Surface plasmon resonance
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Efficient visible light initiated hydrothiolations of alkenes/alkynes over Ir_(2)S_(3)/ZnIn2S4:Role of Ir_(2)S_(3) 被引量:1
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作者 Xinglin Wang Yuanyuan Li Zhaohui Li 《Chinese Journal of Catalysis》 SCIE EI CAS CSCD 2021年第3期409-416,共8页
The hydrothiolations of alkynes/alkenes with thiols is an atom-economic and thus attractive method for the constructions of C‒S bonds.Here Ir_(2)S_(3)/ZnIn_(2)S_(4)nanocomposites with varied Ir_(2)S_(3)loadings were o... The hydrothiolations of alkynes/alkenes with thiols is an atom-economic and thus attractive method for the constructions of C‒S bonds.Here Ir_(2)S_(3)/ZnIn_(2)S_(4)nanocomposites with varied Ir_(2)S_(3)loadings were obtained by one-pot solvothermal method from ZnCl_(2),InCl_(3)and thioacetamide with IrCl_(3).The loading of Ir_(2)S_(3)on the surface of ZnIn_(2)S_(4)promoted the hydrothiolations of alkenes and alkynes,with an optimum performance observed over 0.5 mol%Ir_(2)S_(3)/ZnIn_(2)S_(4)nanocomposite.Based on the studies on the performance of several other cocatalysts(MoS2,NiS and Pd)loaded ZnIn_(2)S_(4)and the EIS analyses,it was proposed that the superior performance over Ir_(2)S_(3)/ZnIn_(2)S_(4)nanocomposite can be ascribed to an improved efficiency on the photogeneration of the thiyl radicals by loading Ir_(2)S_(3)as well as its inactivity for photocatalytic hydrogen evolution,a side reaction in the light initiated hydrothiolation reaction over ZnIn_(2)S_(4).This study not only demonstrates an efficient and green strategy to synthesize thiolated products under visible light based on semiconductor photocatalysis,but also provides some guidances for the design and development of photocatalytic systems for light induced organic syntheses. 展开更多
关键词 PHOTOCATALYSIS Ir_(2)S_(3)/ZnIn_(2)S_(4) ALKENES alkyneS HYDROTHIOLATION
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Higher Order Cuprate Species( Ⅱ )——Stereospecific Carbocupration of Terminal Alkynes and Its Synthetic Utility for ( ± )-Ipsenol and (E)-β-Farnesene
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作者 PAN Yi-jun , XU Zhang-huang, CHEN Jia-wei SUN Dong-chen (Department of Chemistry, Hubei University, Wuhan, 430062) To whom correspondence should be addressed. 《Chemical Research in Chinese Universities》 SCIE CAS CSCD 1993年第2期104-109,共6页
The stereospecific carbocupration of terminal alkynes via higher order cuprates to give 1,1'-disubstituted olefins with 99% configuration purity is described. Its synthetic utility as a general method for the prep... The stereospecific carbocupration of terminal alkynes via higher order cuprates to give 1,1'-disubstituted olefins with 99% configuration purity is described. Its synthetic utility as a general method for the preparation of substituted olefins is further illustrated by the direct synthesis of (±)-ipsenol and (E)-β-farnesene with highly geometric purity of the carbon-carbon double bond. 展开更多
关键词 Higher order cuprate Terminal alkyne Carbocupration STEREOSPECIFIC
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A DFT Study of Alkenes and Alkynes Reacting with H-GaN (0001) Surface
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作者 胡春丽 陈勇 +1 位作者 李俊篯 章永凡 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2009年第1期125-131,共7页
The addition reactions of alkenes and alkynes to the H-terminated GaN (0001) surface with a Ga dangling-bond have been studied employing periodic density functional theory (PDFT) calculations. Detailed information... The addition reactions of alkenes and alkynes to the H-terminated GaN (0001) surface with a Ga dangling-bond have been studied employing periodic density functional theory (PDFT) calculations. Detailed information on the reaction pathways of these alkenes and alkynes with H-GaN (0001) surface is provided, which indicates that the reactions contain two steps separated by the metastable intermediates: elementary addition reaction and H-abstraction process. From the energy curves, the reactions are clearly viable in the cases of ethene, styrene and phenylacetylene; while for ethyne, the H-abstraction barrier is higher than the desorption barrier of the intermediate, so the adsorbed C2H2 in intermediate is more likely to be desorbed back into the gas phase than to form a stable adsorbed species. Furthermore, it is obvious that for either alkenes or alkynes, the systems substituted by phenyl have more stable intermediates because π conjugation could improve their stabilities. 展开更多
关键词 ALKENES alkyneS H-GaN (0001) surface DFT reaction pathway
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A Facile Stereospecific Synthesis of 1, 3-Enynylsulfides via Sonogashira Coupling of (E)-a-Iodovinyl Sulfides with 1-Alkynes
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作者 Jian Wen JIANG Ming Zhong CAI 《Chinese Chemical Letters》 SCIE CAS CSCD 2006年第6期757-760,共4页
(E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the correspo... (E)-α-Iodovinyl sulfides 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol % of Pd(PPh3)4 and 10 mol % of CuI to afford the corresponding 1, 3-enynylsulfides 3 stereospecifically in high yields. 展开更多
关键词 (E)-α-Iodovinyl sulfide 1 3-enynylsulfide Sonogashira coupling terminal alkyne.
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A facile stereospecific synthesis of (Z)-2-sulfonyl-substituted 1,3-enynes via Sonogashira coupling of (E)-α-iodovinyl sulfones with 1-alkynes
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作者 Wen Yan Hao Jian Wen Jiang Ming Zhong Cai 《Chinese Chemical Letters》 SCIE CAS CSCD 2007年第7期773-776,共4页
(E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically af... (E)-α-Iodovinyl sulfones 1 underwent the Sonogashira coupling reactions with terminal alkynes 2 in piperidine at room temperature in the presence of 5 mol% of Pd(PPh3)4 and 10 mol% of CuI to stereospecifically afford the corresponding (Z)-2-sulfonyl-substituted 1,3-enynes 3 in high yields. 展开更多
关键词 (E)-α-Iodovinyl sulfone 1 3-Enynylsulfone Sonogashira coupling Terminal alkyne
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Organic Polyvalent Iodinc Reagents-Promoted Coupling Reaction of 1-Alkynes
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作者 Jun Hua WANG Xian HUANG(Department of Chemistry. Zhejiang University Campus Xixi . Hangzhou 310028) 《Chinese Chemical Letters》 SCIE CAS CSCD 1999年第7期529-530,共2页
Teminal alkynes couple smoothly in the presence of PhI(OAc)2 or PhI(OH)OTs.catalytie Cul and base. affording conjugated diynes.
关键词 Terminal alkynes coupling organic polyvalent iodine compounds conjugated diynes
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Synthesis and Crystal Structure of μ_4-alkyne Cluster Complex (μ_4-η^(2)-C_2Ph_2) Co_4 (CO)_8 (μ-CO)_2
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作者 宋礼成 申金玉 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 1995年第4期281-285,共5页
The cluster complex (μ4-η2-C2Ph2) Co4 (CO)8 (μ-CO)2 was synthesized by 'one pot' method starting from Co2(CO)8 and PhCCPh in toluene and characterized by single-crystal structure analysis. It crystallizes i... The cluster complex (μ4-η2-C2Ph2) Co4 (CO)8 (μ-CO)2 was synthesized by 'one pot' method starting from Co2(CO)8 and PhCCPh in toluene and characterized by single-crystal structure analysis. It crystallizes in the monoclinic space group P21/c with a=9. 149(3). b=11. 732(2), c=23.551 (6) A, β=92. 62(2)°, V=2525 (1), Z=4, Dc= 1. 83 g/cm3,Mr = 694. 07.μ=26.33cm-1,F(000)=1368. The final R= 0. 039, Rω= 0. 047 for 2812 observed independent reflections(I≥3σ(I)). In the molecule, four cobalt atoms form a butterflyshaped metal skeleton and the ligand C2Ph2 is coordinated to cobalt atoms through two σ bonds and a delocalized four- center π-bonding system. 展开更多
关键词 crystal structure alkyne complex. cobalt complex
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