351
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Yuan XY, Li HY, Hodge P, Kilner M, Tastard CY, Zhang ZP. An easy synthesis of robust polymer-supported chiral 1,1′-bi-(2-naphthol)s (BINOLs): application to the catalysis of the oxidation of prochiral thioethers to chiral sulfoxides. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2006.08.011] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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352
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Wang YW, Liu WS, Tang N, Tan MY, Yu KB. Structure and fluorescence properties of a europium complex with N-ethyl-2-{2′-[(ethylphenylcarbamoyl) methoxy]-[1,1′]binaphthalenyl-2-yloxy}-N-phenylacetamide. J COORD CHEM 2006. [DOI: 10.1080/00958970500070459] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Ya-Wen Wang
- a Department of Chemistry and State Key Laboratory of Applied Organic Chemistry , College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China
| | - Wei-Sheng Liu
- a Department of Chemistry and State Key Laboratory of Applied Organic Chemistry , College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China
| | - Ning Tang
- a Department of Chemistry and State Key Laboratory of Applied Organic Chemistry , College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China
| | - Min-Yu Tan
- a Department of Chemistry and State Key Laboratory of Applied Organic Chemistry , College of Chemistry and Chemical Engineering, Lanzhou University , Lanzhou 730000, China
| | - Kai-Bei Yu
- b Chengdu Center of Analysis and Measurement , Academia Sinica , Chengdu 610041, China
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353
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Li J, Zhao J. Chiral Cadmium(II), Nickel(II) Complexes of C2-symmetric (R,R)-et-pybox: Syntheses, Crystal Structures and Spectral Properties. Z Anorg Allg Chem 2006. [DOI: 10.1002/zaac.200600077] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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354
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Kang JE, Kim HB, Lee JW, Shin S. Gold(I)-Catalyzed Intramolecular Hydroamination of Alkyne with Trichloroacetimidates. Org Lett 2006; 8:3537-40. [PMID: 16869654 DOI: 10.1021/ol061307r] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
[reaction: see text] A study on the gold (I)-catalyzed intramolecular hydroamination of trichloroacetimidates derived from propargyl and homopropargyl alcohols is described. In the presence of 2-5 mol % of cationic Au(I) complex, a variety of trichloroacetimidates undergo efficient hydroamination under an exceptionally mild condition. An orthogonality of the current catalytic protocol with those using a stoichiometric electrophile as well as a preliminary synthetic application as a stable precursor of 2-acylamino-1,3-diene has been demonstrated.
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Affiliation(s)
- Ji-Eun Kang
- Department of Chemistry, Hanyang University, 17 Haengdang-dong, Seongdong-gu, Seoul 133-791, Korea
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355
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Shirotani D, Suzuki T, Kaizaki S. Novel Configurational Structures of Sodium Tetrakis(3-heptafluorobutylryl-(+)-camphorato) Ln(III) Complexes with a Trapped Na+ by Na+···FC Interactions in the Solid State and in Solution. Inorg Chem 2006; 45:6111-3. [PMID: 16878913 DOI: 10.1021/ic0606633] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
For newly prepared sodium tetrakis(3-heptafluorobutylryl-(+)-camphorato) Ln(III) complexes, the X-ray crystal analysis revealed an unprecedented pseudo-achiral dodecahedron (DD-8 (D(2d))), whereas in CHCl3 solution, the exciton CD and 19F NMR spectra showed a novel chiral Delta-SAPR-8 (C4) configuration which is stereospecifically formed by a trapped Na+ ion with Na+...FC (fluorocarbon) interactions.
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Affiliation(s)
- Dai Shirotani
- Department of Chemistry, Graduate School of Science, Osaka University, Toyonaka, Osaka 560-0043
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356
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357
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Tsukube H, Onimaru A, Shinoda S. Anion Sensing with Luminescent Tris(β-diketonato)europium(III) Complexes and Naked-Eye Detection of Fluoride Anion. BULLETIN OF THE CHEMICAL SOCIETY OF JAPAN 2006. [DOI: 10.1246/bcsj.79.725] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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358
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Wooten AJ, Carroll PJ, Walsh PJ. Evidence for Substrate Binding by the Lanthanide Centers in [Li3(thf)n(binolate)3Ln]: Solution and Solid-State Characterization of Seven- and Eight-Coordinate [Li3(sol)n(binolate)3Ln(S)m] Adducts. Angew Chem Int Ed Engl 2006; 45:2549-52. [PMID: 16544352 DOI: 10.1002/anie.200504275] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Alfred J Wooten
- P. Roy and Diana T. Vagelos Laboratories, Department of Chemistry, University of Pennsylvania, 231 South 34th Street, Philadelphia, PA 19104-6323, USA
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359
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Wooten AJ, Carroll PJ, Walsh PJ. Evidence for Substrate Binding by the Lanthanide Centers in [Li3(thf)n(binolate)3Ln]: Solution and Solid-State Characterization of Seven- and Eight-Coordinate [Li3(sol)n(binolate)3Ln(S)m] Adducts. Angew Chem Int Ed Engl 2006. [DOI: 10.1002/ange.200504275] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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360
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Enantiopure Chiral Macrocyclic Lanthanide Complexes Derived from (R)-2,2′-Diamino-1,1′-binaphthyl and 2,6-Diformylpyridine. J INCL PHENOM MACRO 2006. [DOI: 10.1007/s10847-005-9028-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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361
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Tobisch S. Mechanism andexo-Regioselectivity of Organolanthanide-Mediated Intramolecular Hydroamination/Cyclization of 1,3-Disubstituted Aminoallenes: A Computational Study. Chemistry 2006; 12:2520-31. [PMID: 16342226 DOI: 10.1002/chem.200501017] [Citation(s) in RCA: 45] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
The complete catalytic reaction course for the organolanthanide-assisted intramolecular hydroamination/cyclization (IHC) of 4,5-heptadien-1-ylamine by a prototypical [(eta(5)-Me5C5)2LuCH(SiMe3)2] precatalyst has been critically scrutinized by employing a reliable DFT method. A computationally verified mechanistic scenario for the IHC of 1,3-disubstituted aminoallene substrates has been proposed that is consistent with the empirical rate law determined by experiment and accounts for crucial experimental observations. It involves kinetically rapid substrate association and dissociation equilibria, facile and reversible intramolecular allenic C=C insertion into the Ln-N bond, and turnover-limiting protonation of the azacycle's tether functionality, with the amine-amidoallene-Ln adduct complex representing the catalyst's resting state. This mechanistic scenario bears resemblance to the mechanism that has been recently proposed in a computational exploration of aminodiene IHC. The unique features of the IHC of the two substrate classes are discussed. Furthermore, the thermodynamic and kinetic factors that control the regio- and stereoselectivity of aminoallene IHC have been elucidated. These achievements have provided a deeper insight into the catalytic structure-reactivity relationships in organolanthanide-assisted cyclohydroamination of unsaturated C-C functionalities.
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Affiliation(s)
- Sven Tobisch
- Institut für Anorganische Chemie der Martin-Luther-Universität Halle-Wittenberg, Fachbereich Chemie, Kurt-Mothes-Strasse 2, 06210 Halle, Germany.
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362
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Riegert D, Collin J, Meddour A, Schulz E, Trifonov A. Enantioselective Intramolecular Hydroamination Catalyzed by Lanthanide Ate Complexes Coordinated by N-Substituted (R)-1,1‘-Binaphthyl-2,2‘-diamido Ligands. J Org Chem 2006; 71:2514-7. [PMID: 16526807 DOI: 10.1021/jo052322x] [Citation(s) in RCA: 147] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Ytterbium and lutetium ionic complexes derived from enantiopure substituted (R)-binaphthylamine ligands, of the general formula [Li(THF)n][Ln[(R)-C20H12(NR)2]2], have been investigated for the hydroamination/cyclization of several aminopentenes and an aminohexene. Complexes with isopropyl or cyclohexyl substituents on nitrogen atoms were found to be efficient catalysts under mild conditions for the formation of N-containing heterocycles with enantiomeric excesses up to 78%.
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Affiliation(s)
- David Riegert
- Laboratoire de Catalyse Moléculaire, ICMMO, UMR CNRS 8182, Université Paris-sud, 91405 Orsay, France
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363
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Wang YW, Liu WS, Yu KB. Spectroscopic and Crystal Structure of Europium(III) Picrate Complexes with Novel BINOL Derivatives. Z Anorg Allg Chem 2006. [DOI: 10.1002/zaac.200500445] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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364
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Bhatt AP, Pathak K, Jasra RV, Kureshy RI, Khan NUH, Abdi SH. Chiral lanthanum–lithium–binaphthol complex covalently bonded to silica and MCM-41 for enantioselective nitroaldol (Henry) reaction. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.molcata.2005.08.045] [Citation(s) in RCA: 61] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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365
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Tran CD, Oliveira D, Yu S. Chiral Ionic Liquid that Functions as Both Solvent and Chiral Selector for the Determination of Enantiomeric Compositions of Pharmaceutical Products. Anal Chem 2006; 78:1349-56. [PMID: 16478133 DOI: 10.1021/ac051897r] [Citation(s) in RCA: 78] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We have successfully synthesized both enantiomers of a novel chiral ionic liquid, (R)- and (S)-[(3-chloro-2-hydroxypropyl) trimethylammonium][bis((trifluoromethyl)sulfonyl)amide] ((R)- and (S)-[CHTA]+[Tf2N]-) in optically pure form by a simple ion exchange reaction from corresponding chloride salts that are commercially available. In addition to the ease of preparation, this chiral IL has relatively high thermal stability (up to 300 degrees C), is liquid at room temperature (glass transition temperature of -58.4 degrees C), and exhibits strong enantiomeric recognition. The high solubility power and strong enantiomeric recognition ability make it possible to use this chiral IL to solubilize an analyte and to induce diastereomeric interactions for the determination of enantiomeric purity. In fact, we have successfully developed a novel method based on the near-infrared technique with this chiral IL serving both as solvent and as a chiral selector for the determination of enantiomeric purity. Enantiomeric compositions of a variety of pharmaceutical products and amino acids with different shape, size, and functional groups can be sensitively (milligram concentration) and accurately (enantiomeric excess as low as 0.6%) determined by use of this method.
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Affiliation(s)
- Chieu D Tran
- Department of Chemistry, Marquette University, P.O. Box 1881, Milwaukee, WI 53201, USA
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366
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Zhou Y, Hong M, Wu X. Lanthanide–transition metal coordination polymers based on multiple N- and O-donor ligands. Chem Commun (Camb) 2006:135-43. [PMID: 16372085 DOI: 10.1039/b509458p] [Citation(s) in RCA: 273] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Lanthanide-transition metal (Ln-M) coordination polymers have attracted extensive interest because they exhibit novel physical properties originating from the interactions between distinct metal ions. This review mainly describes our recent work in the design of Ln-M coordination polymers through the assembly of different metal ions and organic ligands, especially the ligands with multiple N- and O-donor atoms. Many of these crystalline Ln-M materials exhibit intriguing structural motifs and interesting magnetic properties.
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Affiliation(s)
- Youfu Zhou
- State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Fuzhou, Fujian 350002, P. R. China
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367
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Paluch M, Lisowski J, Lis T. Lanthanide complexes of chiral 3 + 3 macrocycles derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol. Dalton Trans 2006:381-8. [PMID: 16365653 DOI: 10.1039/b502863a] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The enantiopure amine macrocycle H(3)L, as well as the parent macrocyclic Schiff base H(3)L1, the 3 + 3 condensation product of (1R,2R)-1,2-diaminocyclohexane and 2,6-diformyl-4-methylphenol, are able to form mononuclear complexes with lanthanide(III) ions. The lanthanide(III) complexes of H(3)L have been studied in solution using NMR spectroscopy and electrospray mass spectrometry. The NMR spectra indicate the presence of complexes of low C(1) and C(2) symmetry. The (1)H and (13)C NMR signals of the Lu(III) complex obtained from H(3)L have been assigned on the basis of COSY, TOCSY, NOESY, ROESY and HMQC spectra. The NMR data reveal unsymmetrical binding of lanthanide(III) ion and the presence of a dynamic process corresponding to rotation of Lu(III) within the macrocycle. The [Ln(H(4)L)(NO(3))(2)](NO(3))(2)(Ln = Sm(III), Eu(III), Dy(III), Yb(III) and Lu(III)) complexes of the cationic ligand H(4)L(+) have been isolated in pure form. The X-ray analysis of the [Eu(H(4)L)(NO(3))(2)](NO(3))(2) complex confirms the coordination mode of the macrocycle determined on the basis of NMR results. In this complex the europium(III) ion is bound to three phenolate oxygen atoms and two amine nitrogen atoms of the monoprotonated macrocycle H(4)L(+), as well as to two axial bidendate nitrate anions. In the presence of a base, mononuclear La(III), Ce(III) and Pr(III) complexes of the deprotonated form of the ligand L(3-) can be obtained. When 2 equivalents of Pr(III) are used in this synthesis Na(3)[Pr(2)L(NO(3))(2)(OH)(2)](2)NO(3).5H(2)O is obtained. The NMR, ES MS and an X-ray crystal model of this complex show coordination of two Pr(III) ions by the macrocycle L. The X-ray crystal structure of the free macrocycle H(3)L1 has also been determined. In contrast to macrocyclic amine H(3)L, the Schiff base H(3)L1 adopts a cone-type conformation resembling calixarenes.
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Affiliation(s)
- Marta Paluch
- Department of Chemistry, University of Wrocław, Poland
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368
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Meermann C, Sirsch P, Törnroos KW, Anwander R. Synthesis and structural characterization of scandium SALEN complexes. Dalton Trans 2006:1041-50. [PMID: 16474890 DOI: 10.1039/b513370j] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of heteroleptic scandium SALEN complexes, [(SALEN)Sc(mu-Cl)]2 and (SALEN)Sc[N(SiHMe2)2] is obtained via amine elimination reactions using [Sc(N(i)Pr2)2(mu-Cl)(THF)]2 and Sc[N(SiHMe2)2]3(THF) as metal precursors, respectively. H(2)SALEN ligand precursors comprising H2Salen [(1,2-ethandiyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol], H2Salpren [(2,2-dimethylpropanediyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol], H2Salcyc [(1R,2R)-(-)-1,2-cyclohexanediyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol] and H2Salphen [((1S,2S)-(-)-1,2-diphenylethandiyl)bis(nitrilomethylidyne)bis(2,4-di-tert-butyl)phenol] are selected according to solubility and ligand backbone variation ("=N-(R)-N=" bite angle) criteria. Consideration is given to the feasibility of [Cl --> NR2] and [N(SiHMe2)2--> OSiR3] secondary ligand exchange reactions. X-ray crystal structure analyses of donor-free (Salpren)Sc(N(i)Pr2), (R,R)-(Salcyc)Sc[N(SiHMe2)2], (Salen)Sc(OSi(t)BuPh2) and (Salphen)Sc(OSiH(t)Bu2) reveal (i) a very short Sc-N bond distance of 2.000(3) A, (ii) weak beta(Si-H)(amido)-Sc agostic interactions and (iii) an exclusive intramolecularly tetradentate and intrinsically bent coordination mode of the SALEN ligands with angle(Ph,Ph) dihedral angles and Sc-[N(2)O(2)] distances in the 124.27(9)-127.7(3) degrees and 0.638(1)-0.688(1) A range, respectively.
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369
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Vale JA, Faustino WM, Menezes PH, de Sá GF. Eu(iii) dithiocarbamate complex and N-p-tolylsulfonylphenylalanine as a novel chiral catalyst for the asymmetric synthesis of cyanohydrins. Chem Commun (Camb) 2006:3340-2. [PMID: 16883430 DOI: 10.1039/b607741m] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The use of a new chiral lanthanide complex derived from a europium dithiocarbamate complex and a N-tosylated amino acid for the asymmetric synthesis of cyanohydrins is described. In some cases, high enantioselectivities were observed.
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Affiliation(s)
- Juliana A Vale
- Departamento de Química Fundamental, Universidade Federal de Pernambuco, 50740-540 Recife/PE, Brazil.
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370
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Hill MS, Hitchcock PB, Mansell SM. Racemic N-aryl bis(amidines) and bis(amidinates): on the trail of enantioselective organolanthanide catalysts. Dalton Trans 2006:1544-53. [PMID: 16538273 DOI: 10.1039/b513521d] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A series of racemic N-aryl-substituted trans-1,2-diaminocyclohexyl (t-1,2-DACH)-linked bis(amidines) were synthesised and their solution behaviour, and solid-state structures were investigated. The amidine functionalities within these compounds were extremely sterically hindered, with ortho-aryl substitution found to hinder N-Ar bond rotation. The results of these studies were used to rationalise the lack of reactivity of these compounds with [Y{N(SiMe(3))(2)}(3)]. Dilithiation of the t-1,2-DACH linked bis(amidines) did, however, proceed easily and the solution behaviour and solid-state structures of the resulting THF-solvated lithium amidinates were investigated. All the compounds showed similar structures in the solid-state, while NMR experiments indicated that the solid-state structures were likely to be maintained in solution. Attempted metathesis reactions with YCl(3) did not, however, yield the desired yttrium chloride complexes.
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Affiliation(s)
- Michael S Hill
- Department of Chemistry, Imperial College London, Exhibition Road, South Kensington, London SW7 2AZ, UK.
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371
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Yan P, Nie C, Li G, Hou G, Sun W, Gao J. Crystal structure of chiral binaphthol lanthanide complexes and their catalysis in asymmetric transfer hydrogenation of acetophenone. Appl Organomet Chem 2006. [DOI: 10.1002/aoc.1058] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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372
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Saá JM, Tur F, González J, Vega M. Chiral monometallic lanthanide(III) salt complexes are arrayed acid–base networks for enantioselective catalysis: a direct, nitroaldol (Henry) reaction. ACTA ACUST UNITED AC 2006. [DOI: 10.1016/j.tetasy.2005.11.014] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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373
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Bag P, Flörke U, Nag K. Synthesis and structural characterization of lanthanide(iii) nitrate complexes of a tetraiminodiphenol macrocycle in the solid state and in solution. Dalton Trans 2006:3236-48. [PMID: 16802042 DOI: 10.1039/b516306d] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The lanthanide(III) complexes [Ln(LH2)(NO3)3] 1-11(La-Er), 15(Y) and [Ln(LH2)(NO3)2(H2O)](NO3) 12-14 (Tm-Lu) of the tetraiminodiphenolate macrocycle L2- have been prepared by the transmetallation reaction between [Pb(LH2)(NO3)2] and Ln(NO3)3.nH2O. In these compounds, the uncoordinated imino nitrogens are protonated and are hydrogen bonded to the phenolate oxygens. The X-ray crystal structures of the La (1), Ho (10) and Lu (14) compounds have been determined. Compounds 1 and 10, in which all the three nitrates are bound in bidentate fashion, are isostructural with distorted bicapped square antiprism geometry for the metal centre. In [Lu(LH2)(NO3)2(H2O)](NO3) 14, of the two metal bound nitrates one is bidentate and the other is unidentate, while the metal centre obtains a distorted square antiprism coordination environment. Proton NMR spectra of the paramagnetic lanthanide complexes have been studied in detail. Contributions of contact and pseudo-contact shifts to the lanthanide induced isotropic shifts (LIS) of the macrocycle protons have been separated and good agreement has been obtained between the calculated LIS values and the experimentally observed values. Analysis of the NMR data has led us to conclude that all the complexes in dimethyl sulfoxide solution attain similar configurations. The absorption and emission spectral characteristic of several compounds have been investigated. The complexes of samarium (5) and europium (6) on photoexcitation at 400 nm exhibit well-resolved luminescence spectra at 77 K both in the solid state and a methanol-ethanol (1 : 4) glassy matrix. For the terbium (8) and dysprosium (9) complexes, however, the observed luminescence peaks are less resolved and weak in intensity.
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Affiliation(s)
- Pradip Bag
- Department of Inorganic Chemistry, Indian Association for the Cultivation of Science, Jadavpur, Kolkata 700 032, India
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374
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Senanayake K, Thompson AL, Howard JAK, Botta M, Parker D. Synthesis and characterisation of dimeric eight-coordinate lanthanide(iii) complexes of a macrocyclic tribenzylphosphinate ligand. Dalton Trans 2006:5423-8. [PMID: 17102868 DOI: 10.1039/b612189f] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The macrocyclic ligand 1,4,7,10-tetraazacyclododecane-1,4,7-triyl(methylenebenzyl-phosphinic acid) H3L3, has been prepared and its complexes with Eu, Gd and Tb(III) studied by NMR, relaxometry, luminescence and single crystal X-ray crystallography. In solution and in the crystal, the complexes have eight-coordinate metal centres with bridging phosphinate groups linking the two twisted square antiprismatic coordination polyhedra. A single stereoisomer crystallises from solution with an RRR and SSS configuration at the P centres in each sub-unit. The relaxivity of [GdL3]2 is low (1.9 mM-1 s-1, 298 K, 20 MHz), consistent with the absence of any proximate water molecules. The terbium dimer possesses a relatively long excited state lifetime (2.47 ms, 298 K).
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Affiliation(s)
- Kanthi Senanayake
- Department of Chemistry, Durham University, South Road, Durham, UK DH1 3LE
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375
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Belen’kii L, Gramenitskaya V, Evdokimenkova Y. The Literature of Heterocyclic Chemistry, Part IX, 2002–2004. ADVANCES IN HETEROCYCLIC CHEMISTRY 2006. [DOI: 10.1016/s0065-2725(06)92004-2] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/30/2022]
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376
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Izarova NV, Sokolov MN, Samsonenko DG, Rothenberger A, Naumov DY, Fenske D, Fedin VP. One-, Two-, and Three-Dimensional Coordination Polymers Built from Large Mo36-Polyoxometalate Anionic Units and Lanthanide Cations. Eur J Inorg Chem 2005. [DOI: 10.1002/ejic.200500484] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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377
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378
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Tobisch S. Organolanthanide-Mediated Intermolecular Hydroamination of 1,3-Dienes: Mechanistic Insights from a Computational Exploration of Diverse Mechanistic Pathways for the Stereoselective Hydroamination of 1,3-Butadiene with a Primary Amine Supported by anansa-Neodymocene-Based Catalyst. Chemistry 2005; 11:6372-85. [PMID: 16086337 DOI: 10.1002/chem.200500355] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The complete catalytic reaction course for the organolanthanide-mediated intermolecular hydroamination of 1,3-butadiene and n-propylamine by an archetypical [Me2Si(eta5-Me4C5)2NdCH(SiMe3)2] precatalyst was critically scrutinized by employing a reliable gradient-corrected DFT method. A free-energy profile of the overall reaction is presented that is based on the thorough characterization of all crucial elementary steps for a tentative catalytic cycle. A computationally verified, revised mechanistic scenario is proposed which is consistent with the experimentally derived empirical rate law and accounts for crucial experimental observations. It involves kinetically mobile reactant association/dissociation equilibria and facile, reversible intermolecular diene insertion into the Nd-amido bond, linked to turnover-limiting protonolysis of the eta3-butenyl-Nd functionality. The computationally predicted effective kinetics (Delta(tot) = 11.3 kcal mol(-1), Delta(tot) = -35.7 e.u.) are in reasonably good agreement with experimental data for the thoroughly studied hydroamination of alkynes. The thermodynamic and kinetic factors that determine the almost complete regio- and stereoselectivity of the mechanistically diverse intermolecular 1,3-diene hydroamination have been unraveled. The present computational study complements experiments because it allows, first, a more detailed understanding and a consistent rationalization of the experimental results for the hydroamination of 1,3-dienes and primary amines and, second, enhances the insights into general mechanistic aspects of organolanthanide-mediated intermolecular hydroamination.
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Affiliation(s)
- Sven Tobisch
- Institut für Anorganische Chemie der Martin-Luther-Universität Halle-Wittenberg, Fachbereich Chemie, Germany.
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379
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Homolysis of the Ln–N bond: Synthesis, characterization and catalytic activity of organolanthanide(II) complexes with furfuryl- and tetrahydrofurfuryl-functionalized indenyl ligands. J Organomet Chem 2005. [DOI: 10.1016/j.jorganchem.2005.06.017] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
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380
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A new example of the three-component reaction: nucleophilic ring opening in cyclopropenones by cyanide ions in the presence of water or alcohols. Russ Chem Bull 2005. [DOI: 10.1007/s11172-006-0087-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/24/2022]
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381
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Aspinall HC, Bickley JF, Greeves N, Kelly RV, Smith PM. Lanthanide Pybox Complexes as Catalysts for Enantioselective Silylcyanation of Aldehydes. Organometallics 2005. [DOI: 10.1021/om050197+] [Citation(s) in RCA: 66] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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382
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Lisowski J, Gregoliński J, Świtalska M, Wiglusz K. New chiral macrocyclic lanthanide complexes derived from (1R,2R)-1,2-diaminocyclohexane and 2,6-diformylpyridine. Inorganica Chim Acta 2005. [DOI: 10.1016/j.ica.2005.03.054] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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383
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Desimoni G, Faita G, Guala M, Laurenti A, Mella M. A New Pyridine-2,6-bis(oxazoline) for Efficient and Flexible Lanthanide-Based Catalysts of Enantioselective Reactions with 3-Alkenoyl-2-oxazolidinones. Chemistry 2005; 11:3816-24. [PMID: 15827979 DOI: 10.1002/chem.200401213] [Citation(s) in RCA: 58] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
Abstract
A new pyridine-2,6-bis(oxazoline) (4) has been easily synthesised from the reaction of (1S,2S)-2-amino-1-phenylpropane-1,3-diol (1) and dimethyl pyridine-2,6-dicarboximidate (2), followed by TIPS (TIPS=triisopropylsilyl) protection of the 4'-CH2OH group. The catalysts derived from 4 and eight lanthanide(III) triflates have been tested over three reactions involving 3-acryloyl- and 3-crotonoyloxazolidinones (5 a,b): the Diels-Alder (DA) reaction with cyclopentadiene, the 1,3-dipolar cycloaddition with diphenyl nitrone and the Mukaiyama-Michael reaction with 2-trimethylsilyloxyfuran. Several reactions exhibit very good enantioselectivity (ee>90 %), and the opposite enantiomers can be easily obtained simply by changing the cation. This specific feature of the ligand can be appreciated in the DA reaction of 5 a, since the catalyst [Sc(III)4] gives the adduct (2'S)-9 a with 99 % ee, whereas the catalyst [Y(III)4] gives the opposite enantiomer with 95 % ee. A rationale of the enantioselectivity is proposed on the basis of the NMR spectra of La-based complexes involving 4 and 5 as ligands.
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Affiliation(s)
- Giovanni Desimoni
- Dipartimento di Chimica Organica, Università di Pavia, Viale Taramelli 10, 27100 Pavia, Italy.
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384
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Wong KL, Law GL, Kwok WM, Wong WT, Phillips DL. Simultaneous Observation of Green Multiphoton Upconversion and Red and Blue NLO Processes from Polymeric Terbium(III) Complexes. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200500031] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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385
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Wong KL, Law GL, Kwok WM, Wong WT, Phillips DL. Simultaneous Observation of Green Multiphoton Upconversion and Red and Blue NLO Processes from Polymeric Terbium(III) Complexes. Angew Chem Int Ed Engl 2005; 44:3436-9. [PMID: 15861449 DOI: 10.1002/anie.200500031] [Citation(s) in RCA: 50] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Ka-Leung Wong
- Department of Chemistry, University of Hong Kong, Pokfulam Road, Hong Kong, P.R. China
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386
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Collin J, Daran JC, Jacquet O, Schulz E, Trifonov A. Lanthanide Complexes Coordinated by N-Substituted (R)-1,1′-Binaphthyl-2,2′-diamido Ligands in the Catalysis of Enantioselective Intramolecular Hydroamination. Chemistry 2005; 11:3455-62. [PMID: 15786500 DOI: 10.1002/chem.200401203] [Citation(s) in RCA: 122] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
A new family of lanthanide ionic complexes derived from chiral, substituted (R)-binaphthylamine ligands, [Li(thf)(4)][Ln{(R)-C(20)H(12)(NR)(2)}(2)] (Ln=Yb, Sm, Nd, or Lu), has been synthesized and characterized by X-ray crystal structure analyses. All complexes have been tested as new catalysts for the hydroamination/cyclization of 1-(aminomethyl)-1-allylcyclohexane. Ytterbium complexes proved to be both the most active and the most enantioselective, and the use of the complex [Li(thf)(4)][Yb{(R)-C(20)H(12)(NC(3)H(7))(2)}(2)], bearing isopropyl radicals on the nitrogen atoms, allowed the formation of the corresponding spiropyrrolidine in high yield with up to 70 % ee.
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Affiliation(s)
- Jacqueline Collin
- Laboratoire de Catalyse Moléculaire, ICMMO, Université Paris-Sud, 91405 Orsay, France
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387
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Mamula O, Lama M, Telfer SG, Nakamura A, Kuroda R, Stoeckli-Evans H, Scopelitti R. A Trinuclear EuIII Array within a Diastereoselectively Self-Assembled Helix Formed by Chiral Bipyridine-Carboxylate Ligands. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200500094] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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388
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Mamula O, Lama M, Telfer SG, Nakamura A, Kuroda R, Stoeckli-Evans H, Scopelitti R. A Trinuclear EuIII Array within a Diastereoselectively Self-Assembled Helix Formed by Chiral Bipyridine-Carboxylate Ligands. Angew Chem Int Ed Engl 2005; 44:2527-31. [PMID: 15786519 DOI: 10.1002/anie.200500094] [Citation(s) in RCA: 74] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- Olimpia Mamula
- Institute of Chemical Sciences and Engineering, Ecole Polytechnique Fédérale de Lausanne, BCH 1403, 1015 Lausanne, Switzerland.
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389
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Mlynarski J, Jankowska J, Rakiel B. Syntheses of chiral hybrid O,N-donor ligands for the investigation of lanthanide complex reactivities in direct aldol condensations. ACTA ACUST UNITED AC 2005. [DOI: 10.1016/j.tetasy.2005.02.023] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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390
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391
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Yamagiwa N, Tian J, Matsunaga S, Shibasaki M. Catalytic Asymmetric Cyano-Ethoxycarbonylation Reaction of Aldehydes using a YLi3Tris(binaphthoxide) (YLB) Complex: Mechanism and Roles of Achiral Additives. J Am Chem Soc 2005; 127:3413-22. [PMID: 15755160 DOI: 10.1021/ja042887v] [Citation(s) in RCA: 94] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Full details of a catalytic asymmetric cyano-ethoxycarbonylation reaction promoted by a heterobimetallic YLi3 tris(binaphthoxide) complex (YLB 1), especially mechanistic studies, are described. In the cyanation reaction of aldehydes with ethyl cyanoformate, three achiral additives, H2O, tris(2,6-dimethoxyphenyl)phosphine oxide (3a), and BuLi, were required to achieve high reactivity and enantioselectivity (up to >99% yield and up to 98% ee). The roles of achiral additives and the reaction pathway were investigated in detail. In situ IR analysis revealed that the initiation step to generate LiCN from H2O, BuLi, and ethyl cyanoformate is rather slow. On the basis of mechanistic studies of the initiation step to generate an active nucleophilic species, reaction conditions were optimized by using a catalytic amount of acetone cyanohydrin as an initiator. Under the optimized conditions, the induction period decreased and the reaction completed within 9 min using 5 mol % YLB at -78 degrees C. Catalyst loading was successfully reduced to 1 mol %. Kinetic experiments and evaluation of the substituent effects of phosphine oxide revealed that phosphine oxide had beneficial effects on both the reaction rate and the enantioselectivity. The putative active species as well as the catalytic cycle of the reaction are also discussed.
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Affiliation(s)
- Noriyuki Yamagiwa
- Graduate School of Pharmaceutical Sciences, The University of Tokyo, Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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392
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Carrée F, Gil R, Collin J. Enantioselective Ring Opening of meso-Epoxides by Aromatic Amines Catalyzed by Lanthanide Iodo Binaphtholates. Org Lett 2005; 7:1023-6. [PMID: 15760129 DOI: 10.1021/ol0475360] [Citation(s) in RCA: 102] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
[reaction: see text] Lanthanide iodo binaphtholates are efficient enantioselective catalysts for the ring opening of meso-epoxides by various aromatic amines. The study of the influence of temperature on the ring opening of cyclohexene oxide by o-anisidine catalyzed by the samarium complex shows an isoinversion effect with the maximum enantiomeric excess at -40 degrees C. Reactions of aniline, o-anisidine, or p-anisidine with five- or six-membered ring epoxides at this temperature allow the preparation of beta-amino alcohols with enantiomeric excesses up to 93%.
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Affiliation(s)
- Fabien Carrée
- Laboratoire de Catalyse Moléculaire, UMR 8075, ICMMO, Bâtiment 420, Université Paris-Sud, 91405, Orsay, France
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393
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Moustiakimov M, Kritikos M, Westin G. First Example of Low-Valence Ion Substitution in Ln5O(OPri)13: Mixed-Valence Europium Oxoalkoxide [EuIII4EuIIO(OPri)12(HOPri)]*HOPri. Inorg Chem 2005; 44:1499-504. [PMID: 15732992 DOI: 10.1021/ic048575a] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The novel mixed-valence alkoxide [Eu3+(4)Eu2+O(OPri)12(HOPri)]HOPri (1) has been prepared and structurally and spectroscopically characterized. The three synthesis routes (i) metathesis of 4EuCl3, EuI2, and 14KOPri combined with hydrolysis with 1H2O, (ii) oxidation of 5[Eu4(OPri)10(HOPri)3]2HOPri with 1.5O2, and (iii) reduction of Eu5O(OPri)13 with 0.8[Eu4(OPri)10(HOPri)3]2HOPri all yielded pure 1, whereas (iv) reduction of Eu5O(OPri)13 with 0.36-0.5 mol of europium metal produced impure 1. The compound, having the average Eu oxidation number +2.8, is very sensitive toward further oxidation to Eu5O(OPri)13 and is part of a redox series of europium 2-propoxides with average oxidation states +2.5, +2.8, and +3. The square pyramidal molecular structure, containing an oxo-oxygen atom in the basal plane, is similar to that of the well-known Ln5O(OPri)13; the main difference is the substitution of an Eu3+(-)OPri pair for an Eu2+(-)HOPri pair in the basal plane. Fourier transform infrared (FT-IR) and UV-visible spectroscopy showed that the solid-state structure was retained on dissolution in hexane and toluene-HOPri. The compound was further characterized by differential scanning calorimetry and solubility studies.
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Affiliation(s)
- Marat Moustiakimov
- Department of Structural Chemistry, Arrhenius Laboratory, Stockholm University, SE-106 91 Stockholm, Sweden
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394
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Takizawa S, Patil ML, Yonezawa F, Marubayashi K, Tanaka H, Kawai T, Sasai H. Micelle-derived polymer supports for enantioselective catalysts. Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2004.12.051] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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395
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Gibson SE, Mainolfi N, Kalindjian SB, Wright PT, White AJP. A New Class of Non-Racemic Chiral Macrocycles: A Conformational and Synthetic Study. Chemistry 2005; 11:69-80. [PMID: 15484182 DOI: 10.1002/chem.200400608] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Amino alcohols have been used to introduce non-racemic chirality into macrocycles using a modular approach that relies on a Heck macrocyclisation reaction. A wide variety of macrocycles have been synthesised, and their structures studied using X-ray crystallography and molecular modelling. A fragmentation reaction encountered during the use of (S)-1,1-dimethylvalinol revealed that carboxylic acids generate acylals under reaction conditions often used for Heck reactions.
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Affiliation(s)
- Susan E Gibson
- Department of Chemistry, Imperial College London, South Kensington Campus, London SW7 2AY, UK.
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396
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Cabeza JA, da Silva I, del Río I, García-Granda S. Crystallographic report: [N,N′-Bis-(6-methylpyrid-2-ylium)-(1R,2R)-1,2-diaminocyclohexane] bis-[(p-cymene)- trichlororuthenate(II)]. Appl Organomet Chem 2005. [DOI: 10.1002/aoc.841] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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397
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Dickins RS, Gaillard S, Hughes SP, Badari A. Asymmetric catalysis by chiral lanthanide complexes in water. Chirality 2005; 17:357-63. [PMID: 15986504 DOI: 10.1002/chir.20171] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The development of catalytic, asymmetric transformations in water is a challenging task. The lanthanides are becoming reagents of choice for many Lewis acid-catalyzed reactions in aqueous media as they are water tolerant. However, enantioselective reactions catalyzed by lanthanides are difficult to achieve in water due to the instability of the reported catalysts. Herein we report the development of stable, well-defined chiral lanthanide complexes and their effectiveness in the asymmetric reduction of alpha-keto acids in aqueous solution. This is the first example of asymmetric reduction by a chiral lanthanide complex in water. Although modest ees are obtained (40-50%) the ytterbium complexes offer a unique advantage as they have the ability to monitor, direct from the reaction mixture, the % ee for the reaction, by 1H NMR, through a dipolar analysis of the observed paramagnetic shift.
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Affiliation(s)
- Rachel S Dickins
- Department of Chemistry, University of Durham, South Road, Durham, United Kingdom.
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398
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Lin Z, Wu M, Wolfbeis OS. Time-resolved fluorescent chirality sensing and imaging of malate in aqueous solution. Chirality 2005; 17:464-9. [PMID: 16104025 DOI: 10.1002/chir.20185] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
Chiral discrimination of malates in aqueous solutions at near-neutral pH is achieved through fluorescence measurement and imaging using the europium-tetracycline complex (EuTc) as a fluorescent probe. The method is based on the significantly different fluorescence properties of the ternary complexes (Eu-Tc-malate) formed between EuTc and the enantiomeric malates. The enantiomeric excess (ee) of chiral malates can be quantified by both steady-state and time-resolved fluorescence, using either a conventional fluorescence microplate reader or fluorescence imaging. It offers a facile and sensitive method for high-throughput chiral discrimination.
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Affiliation(s)
- Zhihong Lin
- Institute of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, Regensburg, Germany
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399
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Vitanova DV, Hampel F, Hultzsch KC. Synthesis and structural characterisation of novel linked bis(β-diketiminato) rare earth metal complexes. Dalton Trans 2005:1565-6. [PMID: 15852102 DOI: 10.1039/b501930c] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Rare earth metal complexes based on novel linked bis(beta-diketiminato) ligands have been prepared via amine elimination and their structural characterisation revealed that the linker unit has significant influence on the geometry and coordination mode of the ancillary ligand.
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Affiliation(s)
- Daniela V Vitanova
- Institut fur Organische Chemie, Friedrich-Alexander Universitat Erlangen-Nurnberg, Henkestrasse 42, D-91054 Erlangen, Germany
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400
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Wiznycia AV, Desper J, Levy CJ. Iron(ii) and zinc(ii) monohelical binaphthyl salen complexes. Chem Commun (Camb) 2005:4693-5. [PMID: 16175295 DOI: 10.1039/b508538a] [Citation(s) in RCA: 30] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A new chiral binaphthyl salen ligand with rigid polyaromatic sidearms gives monohelical complexes (Fe(II) and Zn(II)) of predetermined handedness.
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Affiliation(s)
- Alexander V Wiznycia
- 111 Willard Hall, Department of Chemistry, Kansas State University, Manhattan, Kansas 66506, USA
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