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1.
Prof. Dr. Mohammed Enamullah Mohammad Mostafizur Rahman Mohammad Khairul Islam Dr. Dennis Woschko Prof. Dr. Christoph Janiak Prof. Dr. Gennaro Pescitelli 《ChemistryOpen》2022,11(7):e202200116
A family of bis[(R or S)-N-1-(Ar)ethylsalicylaldiminato-κ2N,O]-Δ/Λ-zinc(II) {Ar=C6H5 (ZnRL1 or ZnSL1), p-CH3OC6H4 (ZnRL2 or ZnSL2) and p-ClC6H4 (ZnRL3 or ZnSL3)} compounds was synthesized and investigated by multiple methods. They feature Λ/Δ-chirality-at-metal induction along the pseudo-C2 axis of the molecules. The chirality induction is quantitative in the solid state, explored by X-ray crystallography and powder X-ray diffraction (PXRD), where R or S-ligated complexes diastereoselectively yield Λ or Δ-configuration at the metal. On the other hand, Λ and Δ-diastereomers co-exist in solution. The Λ⇆Δ equilibrium is solvent- and temperature-dependent. Electronic circular dichroism (ECD) spectra confirm the existence of a diastereomeric excess of Λ-ZnRL1−3 or Δ-ZnSL1−3 in solution. DSC analysis reveals thermally induced irreversible phase transformation from a crystalline solid to an isotropic liquid phase. ECD spectra were reproduced by DFT geometry optimizations and time-dependent DFT (TD-DFT) calculations, providing ultimate proof of the dominant chirality atmetal in solution. 相似文献
2.
Klaus Bernauer Helen Stoeckli-Evans Deirdre Hugi-Cleary Hermann J. Hilgers Habib Abd-el-Khalek Joëlle Porret Jean-Jacques Sauvain 《Helvetica chimica acta》1992,75(7):2327-2339
The syntheses and characterization of four new linear pentadentate ligands and their CoIII complexes are described: N,N′-[(pyridine-2,6-diy)bis(methylene)]bis[sarcosine] (sarmp), N,N′-[(pyridine-2,6-diyl)bis(methylene)]bis[(R)- or (S)-proline] ((R,R)- or (S,S)-promp), N,N′-[(pyridine-2,6-diyl)bis(methylene)]bis[N-(methyl)-(R)- or (S)-alanine] ((R,R)- or (S,S)-malmp); 2,2′-[pyridine-2,6-diyl]bis[(S)- or rac-N-(acetic acid)pyrrolidine] ((S,S)- or rac-bapap). The complexes were characterized and, with but one exception, complex formation is stereospecific: Δ-exo-(R,R) (or Λ-exo-(S,S)) for promp and Λ-(R,R) (or Δ-(S,S)) for bapap. The exception is [Co((R,R)- or (S,S)-malmp)H2O]ClO4 for which two forms are obtained, to which Λ-endo-(R,R) (or Δ-endo-(S,S)) and, tentatively, Δ-unsymmetric-(R,R)- (or Λ-unsymmetric-(S,S)-) configurations are assigned. X-Ray crystal structures are presented for the complexes [Co(sarmp)H2O]ClO4, [Co((S,S)-promp)H2O]ClO4, [Co(rac-bapap)H2O]ClO4 and endo-[Co(rac-malmp)H2O]ClO4. Ligand acid dissociation and CoII and FeII complex-formation constants are reported. 相似文献
3.
《Journal of Coordination Chemistry》2012,65(23):4107-4118
Chiral aminoalcohol based Schiff bases (R or S)-2-{(E)-(2-hydroxy-1-phenylethylimino)methyl}phenol and (R/S)-2-{(E)-(2-hydroxy-2-phenylethylimino)methyl}phenol coordinate to copper(II)acetate to give enantiopure Λ/Δ- or Δ/Λ-bis[(R or S)-2-{(E)-(2-hydroxy-1-phenylethylimino)methyl}phenoxide-κ2N,O]copper(II), {Λ/Δ-Cu(R-L1)2 (1) or Δ/Λ-Cu(S-L1)2 (2)}, and racemic Δ/Λ- and Λ/Δ-bis[(R/S)-2-{(E)-(2-hydroxy-2-phenylethylimino)methyl}phenoxide-κ2N,O]copper(II), {Δ/Λ- and Λ/Δ-Cu(R/S-L2)2 (3)}, respectively. The complexes are characterized by elemental analyzes, IR, UV–Vis, polarimetry, circular dichroism (CD), differential scanning calorimeter (DSC), and mass spectroscopy. Polarimetry shows the rotation to the left at ?113.6° (1) and to the right at +106.4o (2). CD spectra show the expected mirror-image relationship with opposite sign of ellipticity maxima (Δεmax = +0.43 for 1 and ?0.42 M?1 dm3 cm?1 for 2 at 638 nm) due to the d-d transitions of the metal ion. CD spectral analyzes further reveal a diastereoselectivity or diastereomeric excess towards Λ-Cu(R-L1)2 or Δ-Cu(S-L1)2 configuration for 1 or 2 in solution. Similarly, the enantiomeric pair of Δ-Cu(R-L2)2 and Λ-Cu(S-L2)2 configurations (CD inactive) for 3 will be preferred in solution. Electronic spectra in different solvents reveal a negative solvatochromism by shifting absorption maxima of the MLCT band to higher energies in solvents of increasing polarity as well as acceptor number. DSC analyzes show an endothermic peak at 525.5 (1) or 528.7 K (2), corresponding to a thermally induced structural phase transformation from distorted square-planar to regular tetrahedral. 相似文献
4.
Prof. Dr. Masayoshi Onishi Yoko Tashiro Dr. Yasuhiro Arikawa Junko Nagaoka Prof. Dr. Keisuke Umakoshi Dr. Yusuke Sunada Prof. Dr. Koichi Nozaki 《化学:亚洲杂志》2011,6(6):1405-1415
Diastereomeric geminate pairs of chiral bis(2‐oxazoline) ruthenium complexes with bipyridyl‐type N‐heteroaromatics, Λ‐ and Δ‐[Ru(L‐ L)2(iPr‐biox)]2+ (iPr‐biox=(4S,4′S)‐4,4′‐diisopropyl‐2,2′‐bis(2‐oxazoline); L‐ L=2,2′‐bipyridyl (bpy) for 1 Λ and 1 Δ, 4,4′‐dimethyl‐2,2′‐bipyridyl (dmbpy) for 2 Λ and 2 Δ, and 1,10‐phenanthroline (phen) for 3 Λ and 3 Δ), were separated as BF4 and PF6 salts and were subjected to the comparative studies of their stereochemical and photochemical characterization. DFT calculations of 1 Λ and 1 Δ electronic configurations for the lowest triplet excited state revealed that their MO‐149 (HOMO) and MO‐150 (lower SOMO) characters are interchanged between them and that the phosphorescence‐emissive states are an admixture of a Ru‐to‐biox charge‐transfer state and an intraligand excited state within the iPr‐biox. Furthermore, photoluminescence properties of the two Λ,Δ‐diastereomeric series are discussed with reference to [Ru(bpy)3]2+. 相似文献
5.
Dr. Deepa Krishnan Dr. Sumod A. Pullarkat Meiyi Wu Dr. Yongxin Li Prof. Pak‐Hing Leung 《Chemistry (Weinheim an der Bergstrasse, Germany)》2013,19(17):5468-5475
Palladium and platinum complexes containing a sulfur‐functionalised N‐heterocyclic carbene (S‐NHC) chelate ligand have been synthesised. The absolute conformations of these novel organometallic S‐NHC chelates were determined by X‐ray structural analyses and solution‐phase 2D 1H–1H ROESY NMR spectroscopy. The structural studies revealed that the phenyl substituents on the stereogenic carbon atoms invariably take up the axial positions on the Pd‐C‐S coordination plane to afford a skewed five‐membered ring structure. All of the chiral complexes are structurally rigid and stereochemically locked in a chiral ring conformation that is either (Rs,S,R)‐λ or (Ss,R,R)‐δ in both the solid state and solution. 相似文献
6.
Dr. Kosuke Higashida Fabian Brüning Nagataka Tsujimoto Kenya Higashihara Dr. Haruki Nagae Prof. Dr. Antonio Togni Prof. Dr. Kazushi Mashima 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(40):8749-8759
We report full details of the synthesis and characterization of monohydride-dichloro rhodium(III) complexes bearing chiral diphosphine ligands, such as (S)-BINAP, (S)-DM-SEGPHOS, and (S)-DTBM-SEGPHOS, producing cationic triply chloride bridged dinuclear rhodium(III) complexes ( 1 a : (S)-BINAP; 1 b : (S)-DM-SEGPHOS) and a neutral mononuclear monohydride-dichloro rhodium(III) complex ( 1 c : (S)-DTBM-SEGPHOS) in high yield and high purity. Their solid state structure and solution behavior were determined by crystallographic studies as well as full spectral data, including DOSY NMR spectroscopy. Among these three complexes, 1 c has a rigid pocket surrounded by two chloride atoms bound to the rhodium atom together with one tBu group of (S)-DTBM-SEGPHOS for fitting to simple olefins without any coordinating functional groups. Complex 1 c exhibited superior catalytic activity and enantioselectivity for asymmetric hydrogenation of exo-olefins and olefinic substrates. The catalytic activity of 1 c was compared with that of well-demonstrated dihydride species derived in situ from rhodium(I) precursors such as [Rh(cod)Cl]2 and [Rh(cod)2]+[BF4]− upon mixing with (S)-DTBM-SEGPHOS under dihydrogen. 相似文献
7.
《Electrochemistry communications》2003,5(5):388-391
A stereoselective solid surface has been created by the self-assembly of a chiral osmium complex, λ-[Os(phen)3](ClO4)2 (phen=1,10-phenanthroline), onto a single layered clay film deposited on an indium tin oxide (ITO) electrode; the OsII–OsIII redox couple mediates the electrochemical oxidation of chiral 1,1′-2-binaphthol in a stereoselective way or the S-isomer is oxidized at 1.4 times higher rate than the R-isomer. 相似文献
8.
Quang H. Luu Prof. Dr. John A. Gladysz 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(45):10230-10239
The chiral enantiopure cobalt(III) complex Δ-[Co((S,S)-dpen)3]3+ 2Cl−B(C6F5)4− (Δ-(S,S)- 2 3+ 2Cl−B(C6F5)4−; dpen=1,2-diphenylethylenediamine) is an effective catalyst, together with pyridine (10 mol % each), for enantioselective additions of substituted cyanoacetate esters NCCH(R)CO2R′ to acetylenic esters R′′C≡CCO2R′′′. In the resulting adducts NC(R′O2C)C(R)CR′′C=CHCO2R′′′, C=C isomers in which the CO2R′′′ moiety is trans to the new carbon–carbon bond dominate (avg. ratio 98:2). These are obtained in 70–98 % ee (avg. 86 %; data for optimum R′ and R′′′), as determined by 1H NMR with the chiral solvating agent Λ-(S,S)- 2 3+ 2I−B(3,5-C6H3(CF3)2)4−. NMR experiments show that the cyanoacetate and acetylenic esters and pyridine can hydrogen bond to certain NH groups of the catalyst. Rates are zero order in the cyanoacetate and acetylenic esters as well as the catalyst, and implications are discussed. 相似文献
9.
Rakesh K. Rath G. A. Nagana Gowda Akhil R. Chakravarty 《Journal of Chemical Sciences》2002,114(5):461-472
2D NMR spectroscopy has been used to determine the metal configuration in solution of three complexes, viz. [(η6-p-cymene)Ru(L*)Cl] (1) and [(η6-p-cymene)Ru(L*)(L′)] (C1O4) (L′ = H2O,2; PPh3,3), where L* is the anion of (S)-(l-phenylethyl)salicylaldimine. The complexes exist in two diastereomeric forms in solution. Both the (RRu,Sc)- and (SRu,Sc)-diastereomers display the presence of attractive CH/π interaction involving the phenyl group attached to the chiral carbon
and the cymene ring hydrogens. This interaction restricts the rotation of the C*-N single bond and, as a result, two structural
types with either the hydrogen atom attached to the chiral carbon (C*) or the methyl group attached to C* in close proximity
of the cymene ring protons get stabilized. Using 2D NMR spectroscopy as a tool, the spatial interaction involving these protons
are studied in order to obtain the metal configuration(s) of the diastereomeric complexes in solution. This technique has
enabled us to determine the metal configuration as (R
Ru,S
c) for the major isomers of 1–3 in solution. 相似文献
10.
《Journal of Coordination Chemistry》2012,65(9):1639-1651
Assemblies between pseudo-enantiomers with different d8 metal centers, Δ-[M(bpy){Co(aet)2(R-pn)}]3+ (M?=?Pd or Pt, bpy?=?2,2′-bipyridine, aet?=?2-aminoethanethiolate, pn?=?1,2-propanediamine), and Λ-[M′(bpy){Co(aet)2(S-pn)}]3+ (M′ ≠ M, M′?=?Pd or Pt), have been examined from stereo- and spectrochemical aspects. A mixture of equimolar amounts of the optically active sulfur-bridged dinuclear complex, Δ-[M(bpy){Co(aet)2(R-pn)}](NO3)3·7H2O, and its pseudo-enantiomer, Λ-[M′(bpy){Co(aet)2(S-pn)}](NO3)3·7H2O, in H2O crystallizes as [M(bpy){Co(aet)2(R-pn)}][M′(bpy){Co(aet)2(S-pn)}](NO3)6·4H2O, in which two complex cations with imperfect enantiomorphisms form a 1?:?1 π–π stacked unit. 相似文献
11.
Reaction of (R,R)-(−)- and (S,S)-(+)-1,2-bis(pyrrol-2-ylmethyleneamino)cyclohexane with K2PtCl4 afforded chiral, neutral platinum(II) Schiff base complexes of (R,R)-PtL and (S,S)-PtL with high yields. The rare C–HPt(II) intermolecular interaction was found to show considerable strength and directionality for controlling M and P helical supramolecular architectures of (R,R)-PtL and (S,S)-PtL, respectively, in crystal lattices. More importantly, the open square-planar geometry of platinum(II) complexes allows axial C–HPt(II) interaction, resulting in the 3(ππ*) excited state with some mixing of the Pt(II) metal character observed both in concentrated solutions and in the solid state at room temperature. 相似文献
12.
Dr. Yosuke Demizu Prof. Mitsunobu Doi Dr. Masaaki Kurihara Prof. Tokumi Maruyama Prof. Hiroshi Suemune Prof. Masakazu Tanaka 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(8):2430-2439
Chiral cyclic α,α‐disubstituted amino acids, (3S,4S)‐ and (3R,4R)‐1‐amino‐3,4‐(dialkoxy)cyclopentanecarboxylic acids ((S,S)‐ and (R,R)‐Ac5cdOR; R: methyl, methoxymethyl), were synthesized from dimethyl L ‐(+)‐ or D ‐(?)‐tartrate, and their homochiral homoligomers were prepared by solution‐phase methods. The preferred secondary structure of the (S,S)‐Ac5cdOMe hexapeptide was a left‐handed (M) 310 helix, whereas those of the (S,S)‐Ac5cdOMe octa‐ and decapeptides were left‐handed (M) α helices, both in solution and in the crystal state. The octa‐ and decapeptides can be well dissolved in pure water and are more α helical in water than in 2,2,2‐trifluoroethanol solution. The left‐handed (M) helices of the (S,S)‐Ac5cdOMe homochiral homopeptides were exclusively controlled by the side‐chain chiral centers, because the cyclic amino acid (S,S)‐Ac5cdOMe does not have an α‐carbon chiral center but has side‐chain γ‐carbon chiral centers. 相似文献
13.
Dr. Enrico Marchi Dr. Riccardo Sinisi Dr. Giacomo Bergamini Dr. Michele Tragni Prof. Dr. Magda Monari Prof. Dr. Marco Bandini Prof. Dr. Paola Ceroni 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(28):8765-8773
A new class of neutral cyclometalated iridium(III) complexes with enantiomerically pure C1‐symmetric phenol‐oxazolines ( 3 a,b ) have been synthetized in high yields and fully characterized. Resolution of the corresponding ΔR and ΛR or ΔS and ΛS isomers was easily achieved by conventional flash chromatography. The corresponding Δ and Λ helicities have been confirmed by CD spectroscopy and X‐ray crystallography. Regarding the absorption and luminescence properties with unpolarized light, no significant difference between Δ and Λ isomers has been observed. A strong blue luminescence is observed for deaerated solutions of complexes 5 a and 5 b in CH3CN. 相似文献
14.
《Journal of Coordination Chemistry》2012,65(4):369-377
The preparation and characterization of zinc complexes of formula ZnL2X2 (X?=?Cl and Br), with L?=?1,3-diazinane-2-thione (Diaz), 1,3-diazipane-2-thione (Diap), imidazolidine-2-thione (Imt) and its methyl and n-propyl substituted derivatives, are described. The complexes dichlorobis(1-methylimidazolidine-2-thione-S)-zinc(II) (1) and dichlorobis(1-propylimidazolidine-2-thione-S)-zinc(II) (2) have been characterized by single-crystal X-ray methods. Both complexes adopt distorted tetrahedral geometry. Only intramolecular hydrogen bonding interactions are observed in 1 and 2. Solution and solid state 13C NMR show a significant shift of the C=S carbon resonance of the ligands, while other resonances are relatively unaffected, indicating that most likely the solid state structure is maintained in solution. Antimicrobial activity studies of the free ligands and their complexes show that ligands exhibit substantial antibacterial activities compared to the complexes. 相似文献
15.
Hans R. Kricheldorf Matthias Berghahn 《Journal of polymer science. Part A, Polymer chemistry》1995,33(3):427-439
Starting from commercial S- or R-3-bromo-2-methylpropanol, several new spacer diols were prepared. These spacers were polycondensed with the acid chloride of N-(4′-carboxyphenyl)trimellitimide. The resulting poly(ester-imide)s were characterized by elemental analyses, viscosity measurements, 1H-NMR spectroscopy, DSC- and WAXD-measurements and optical microscopy. The poly(ester-imide)s derived from chiral, aliphatic spacers form layer structures in the solid state, but no liquid crystalline phase. With nonsymmetrical, nonchiral semialiphatic spacers, poly(ester-imide)s were obtained, which form a smectic E or H phase in the solid state, a smectic-A or -C phase in the melt, and a nematic phase, when the spacer possesses an odd number of CH2 groups. The polycondensation of a chiral semialiphatic spacer yielded thermotropic poly(ester-imide)s with either S- or R-configuration. WAXD patterns measured with synchrotron radiation at various temperatures proved that a layer structure exists in the solid state (smectic-E* or H*) and a chiral smectic-A* or -C* phase plus a cholesteric phase in the melt. A 1 : 1 blend of the S- and R-polyesters was also studied, but did not show unusual features. © 1995 John Wiley & Sons, Inc. 相似文献
16.
Francesco Dallavalle Giuseppina Folesani Enrico Leporati Gianni Galaverna 《Helvetica chimica acta》1996,79(7):1818-1824
Formation constants of ternary complexes of CuII with (S)-amino-acid amides ((S)-phenylalaninamide, (S)-prolinamide, and (S)-tryptophanamide) and (R)- or (S)-histidine and (R)- or (S)-tyrosine were determined potentiometrically in aqueous solution. Significant stereoselectivity was presented by all three amides towards histidine, the diastereoisomeric complexes with ‘heterochiral’ ligands being more stable than those with ‘homochiral’ ligands (see Table 3). The stereoselectivity observed with (S)-phenylalaninamide and (S)-tryptophanamide may be explained on the basis of hydrophobic stacking interactions between 1H-imidazole and the aromatic side chain, favoured by the terdentate behaviour of histidine (see Fig.2), whereas repulsive effects seem to be prevalent with (S)-prolinamide. Only (S)-prolinamide and (S)-phenylalaninamide show appreciable stereoselectivity with tyrosine, which is bidentate, probably on account of repulsive interactions. The present results on the stability of ternary complexes in solution allow to draw some conclusions on the mechanism of chiral discrimination performed by CuII complexes of (S)-amino-acid amides added to the mobile phase in HPLC (reversed phase). 相似文献
17.
Assembling Quasi‐enantiomeric Octahedral Complexes of Different Metals via Quasi‐racemate Crystallization
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Yanay Popowski Prof. Israel Goldberg Prof. Moshe Kol 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(16):5530-5533
Aiming at a general methodology for binary co‐assembly of complexes of different metals through quasiracemate crystallization, the hexadentate ligand 1 comprised of the chiral bipyrrolidine core and two bipyridine peripheral arms is introduced. Ligand 1 was found to bind in a fully diastereoselective and uniform mode around ZnII, FeII and CdII giving coordinatively inert octahedral “chiral‐at‐metal” complexes with the Δ4Λ2/Λ4Δ2 wrapping mode. Equimolar mixtures of quasienantiomeric pairs of these complexes exhibited a clear tendency to pack as quasiracemates as was revealed from the crystallographic structures of [(R,R)‐ 1 ‐Zn](PF6)2/[(S,S)‐ 1 ‐Fe](PF6)2 and [(R,R)‐ 1 ‐Zn](PF6)2/[(S,S)‐ 1 ‐Cd](PF6)2, in an isomorphous fashion to that of the racemic compound [rac‐ 1 ‐Zn](PF6)2 in space group C2/c. 相似文献
18.
Anurag Mukherjee Prof. Dr. Suhrit Ghosh 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(56):12874-12881
H-bonding driven J-type aggregation and cooperative supramolecular polymerization of a sulfur-substituted chiral naphthalene-diimide (NDI)-derivative (S,S)-NDI-2 in decane leads to remarkable enhancement of fluorescence quantum yield (43.3 % from 0.5 % in the monomeric state) and intense CPL signal in the aggregated state with a high luminescence dissymmetry factor (glum) of 4.6×10−2. A mixture of NDI-2 with a structurally similar NDI-derivative NDI-1 (mixture of racemic (S,S)- and (R,R)- isomers and the achiral derivative) in 1:9 (NDI-2/NDI-1) ratio, when heated and slowly cooled to room temperature, showed no enhanced CD band, indicating lack of any preferential helicity. However, when a monomeric solution of the NDI-1 in tetrahydrofuran (THF) was injected to preformed seed of NDI-2 in decane, a prominent CD signal appeared, indicating chiral amplification resulting in induced CPL with high glum value of 2.0×10−2 from mostly (>98.5 %) diastereomeric mixture. 相似文献
19.
《Journal of Coordination Chemistry》2012,65(6):613-620
Circular dichroism spectra of the fac and mer isomers of tris-cobalt(III) complexes of S-2,3-Hdap (Hdap?=?diaminopropionic acid); fac and mer-[Co(S-dap)3] (Λ or Δ), and [Co(en)3]3+ (Λ or Δ, en?=?ethylenediamine) in an aqueous solution without and upon IR irradiation were measured. The detection of the propelling motion that corresponds to circular dichroism spectral changes of the propeller-type complex, fac-[Co(S-dap)3] in an aqueous solution upon IR irradiation gave good agreement with the computer-simulation result, that is, the propelling (translation and rotation) motion occurs in propeller-type metal complexes in aqueous solution as a consequence of an appropriate energy supply, which had been obtained by theoretical study based on molecular dynamics (MD) simulations by the use of AMBER 6 program. 相似文献
20.
Kenjiro Onimura Yuan Zhang Michihiro Yagyu Tsutomu Oishi 《Journal of polymer science. Part A, Polymer chemistry》2004,42(18):4682-4692
Chiral (S)-(−)-N-1-cyclohexylethylmaleimide [(S)-CEMI] and (R)-(+)-N-1-cyclohexylethylmaleimide [(R)-CEMI] were synthesized successfully and then polymerized with chiral complexes of (−)-sparteine or (S,S)-(1-ethylpropylidene)bis(4-benzyl-2-oxazoline) [(S,S)-Bnbox] and organometal as initiators in toluene or tetrahydrofuran to obtain optically active polymers. The effects of the polymerization conditions on the optical activity and structure of poly(N-1-cyclohexylethylmaleimide)s were investigated with gel permeation chromatography, circular dichroism, specific rotation, and 13C NMR measurements. Poly[(R)-CEMI] obtained with dimethylzinc (Me2Zn)/(S,S)-Bnbox had the highest specific rotation ([α]435 = +323.7°). Complexes of Bnbox and diethylzinc or Me2Zn were used very effectively as chiral initiators for the asymmetric anionic polymerization of (S)-CEMI and (R)-CEMI. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 4682–4692, 2004 相似文献