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Shuli You - One of the best experts on this subject based on the ideXlab platform.
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asymmetric c h bond functionalization of Ferrocenes new opportunities and challenges
Trends in Chemistry, 2020Co-Authors: Chenxu Liu, Shuli YouAbstract:Ferrocene is of great significance in the fields of organic synthesis, materials science, and biomedical research. Of particular importance is the fact that Ferrocenes with planar chirality have proven to be privileged ligands or catalysts for asymmetric catalysis. Therefore, developing highly efficient methods to introduce planar chirality on the backbone of ferrocene is desirable. This short review highlights recent advances towards enantioselective C–H bond functionalization of Ferrocenes. Enantioselective synthesis of planar chiral Ferrocenes via Pd-, Ir-, Rh-, Au-, Pt-, and Ni-catalyzed C–H bond functionalization is described. The achievements in asymmetric C–H bond functionalization provide a rich platform for the design and synthesis of planar chiral Ferrocenes.
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cp co iii catalyzed ortho c h amidation of 2 pyridinyl Ferrocenes with 1 4 2 dioxazol 5 ones
Journal of Catalysis, 2018Co-Authors: Shaobo Wang, Shuli YouAbstract:ortho-Amidation of 2-pyridinyl Ferrocenes with 1,4,2-dioxazol-5-ones was achieved via Cp*Co(III)-catalyzed direct C-H bond functionalization reaction. In the presence of Cp*Co(CO)I-2, in combination with AgPF6 and AgOPiv, a wide range of ferrocene-based amidated products were obtained in up to 96% yield under mild reaction conditions. A gram-scale reaction proceeded smoothly with high efficiency. Isoquinoline and pyrimidine are also suitable directing groups in this transformation. (C) 2018 Elsevier Inc. All rights reserved.
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enantioselective synthesis of planar chiral Ferrocenes via pd 0 catalyzed intramolecular direct c h bond arylation
Journal of the American Chemical Society, 2014Co-Authors: Dewei Gao, Qin Yin, Shuli YouAbstract:A highly efficient synthesis of planar chiral Ferrocenes by enantioselective Pd(0)-catalyzed direct C–H arylation from readily available starting materials under mild reaction conditions was developed (up to 99% yield, 99% ee). The products can be easily transformed to the highly efficient planar ferrocene ligands, which have demonstrated high efficiency in Pd-catalyzed asymmetric allylic alkylation and amination reactions.
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enantioselective synthesis of planar chiral Ferrocenes via palladium catalyzed annulation with diarylethynes
Beilstein Journal of Organic Chemistry, 2013Co-Authors: Yanchao Shi, Rongfei Yang, Dewei Gao, Shuli YouAbstract:When Boc-L-Val-OH was used as a ligand for the enantioselective Pd(II)-catalyzed annulation of N,N-substituted aminomethyl ferrocene derivatives with diarylethynes, Ferrocenes with planar chirality could be achieved with excellent enantioselectivity (up to 99% ee).
Eiichi Nakamura - One of the best experts on this subject based on the ideXlab platform.
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Sharing orbitals: ultrafast excited state deactivations with different outcomes in bucky Ferrocenes and ruthenocenes.
Journal of the American Chemical Society, 2006Co-Authors: Dirk M. Guldi, G. M.aminur Rahman, Renata Marczak, Yutaka Matsuo, Masahiro Yamanaka, Eiichi NakamuraAbstract:We report on the singlet ground and singlet/triplet excited-state features of a series of bucky Ferrocenes, bucky ruthenocenes, and respective reference compounds. In the bucky ferrocene conjugates, intimate contacts between the fullerenes and Ferrocenes result in appreciable ground-state interactionssuggesting a substantial shift of charge density from the electron donor (i.e., ferrocene) to the electron acceptor (i.e., fullerene). In contrast, no prominent charge-transfer features were observed for the bucky ruthenocene conjugates. An arsenal of experimental techniques, ranging from fluorescence (i.e., steady state and time-resolved) and pump probe experiments (i.e., femtosecond and nanoseconds) to pulse radiolysis, were employed to examine excited-state interactions. In the excited states, bucky ferrocene conjugates are dominated by rapid charge separation reactions (0.8 ± 0.1 ps) to yield metastable radical ion pairs. The radical ion pair lifetimes vary between 27 and 39 ps. No charge separation was, ...
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mossbauer spectroscopy of bucky Ferrocenes lattice dynamics and motional anisotropy of the metal atom
Inorganic Chemistry, 2005Co-Authors: Rolfe H Herber, Motoki Toganoh, Yutaka Matsuo, Yoichiro Kuninobu, I Nowik, Eiichi NakamuraAbstract:Temperature-dependent 57Fe Mossbauer effect spectroscopy has been used to elucidate the metal atom dynamics in three neutral and two cationic bucky Ferrocenes. For the three diamagnetic complexes Fe(C60H5)Cp (1), Fe(C60Me5)Cp (2), and Fe(C60Ph5)Cp (3), the metal atom motion is anisotropic and the temperature dependence of the mean-square amplitude of vibration of the metal atom at a number of temperatures is reported. The Mossbauer lattice temperatures have been determined and compared to the parent ferrocene (6). The synthesis and X-ray crystal structure of 3 have been determined at 153(2) K, and the 1H and 13C NMR spectra have been recorded. The cationic complexes derived from 2 and 3 show spin−lattice relaxation. The relaxation rate appears insensitive to the nearest-neighbor environment of the metal atom in this pair.
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Synthesis of ferrocene/hydrofullerene hybrid and functionalized bucky Ferrocenes.
Journal of the American Chemical Society, 2003Co-Authors: Motoki Toganoh, Yutaka Matsuo, Eiichi NakamuraAbstract:Hydroferration reaction of [60]fullerene or its derivative with [Fe(C5H5)(CO)2]2 gives regioselectively a ferrocene/hydrofullerene hybrid, which upon treatment with Bu4NOH and an alkyl halide affords the corresponding alkylated bucky ferrocene, again regioselectivity via an anion of the ferrocene.
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synthesis of ferrocene hydrofullerene hybrid and functionalized bucky Ferrocenes
Journal of the American Chemical Society, 2003Co-Authors: Motoki Toganoh, Yutaka Matsuo, Eiichi NakamuraAbstract:Hydroferration reaction of [60]fullerene or its derivative with [Fe(C5H5)(CO)2]2 gives regioselectively a ferrocene/hydrofullerene hybrid, which upon treatment with Bu4NOH and an alkyl halide affords the corresponding alkylated bucky ferrocene, again regioselectivity via an anion of the ferrocene.
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Bucky ferrocene. Hybrid of ferrocene and fullerene
Pure and Applied Chemistry, 2003Co-Authors: Eiichi NakamuraAbstract:The idea of "bucky ferrocene" intrigues chemists owing to its aesthetic beauty and to its polarized, extended conjugated system, but the idea has remained hypothetical. The syn- thesis of close analogs of Fe(C 60 Me 5 )Cp and Fe(C 70 Me 3 )Cp was achieved in two steps from (60) and (70)fullerenes, relying on an oxidative C-H bond activation starting with an iron(I) complex and the corresponding cyclopentadienyl precursors, respectively. The molecules can be regarded as members of a new organometallic conjugated system connected to a graphitic system. Numerous synthetic transformations and self-organization procedures that are known for the parent Ferrocenes and fullerenes are expected to be employable toward productive use of the ferrocene/fullerene hybrid molecules in chemistry and materials sciences.
Bingfeng Shi - One of the best experts on this subject based on the ideXlab platform.
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amide directed cobalt iii catalyzed c h amidation of Ferrocenes
Organic Letters, 2019Co-Authors: Danying Huang, Qijun Yao, Shuo Zhang, Kun Zhang, Bingfeng ShiAbstract:The amide-directed cobalt(III)-catalyzed C–H amidation of ferrocene carboxamides using 1,4,2-dioxazol-5-ones as robust and efficient amidating reagents has been developed. This reaction proceeds efficiently under mild reaction conditions with good functional group tolerance, providing expedient access to a broad range of Ferrocenes containing a nitrogen group on the Cp ring.
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Amide-Directed Cobalt(III)-Catalyzed C–H Amidation of Ferrocenes
2019Co-Authors: Danying Huang, Qijun Yao, Shuo Zhang, Kun Zhang, Bingfeng ShiAbstract:The amide-directed cobalt(III)-catalyzed C–H amidation of ferrocene carboxamides using 1,4,2-dioxazol-5-ones as robust and efficient amidating reagents has been developed. This reaction proceeds efficiently under mild reaction conditions with good functional group tolerance, providing expedient access to a broad range of Ferrocenes containing a nitrogen group on the Cp ring
Florence Mongin - One of the best experts on this subject based on the ideXlab platform.
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Fluoro- and Chloroferrocene From 2-to 3-Substituted Derivatives
Organometallics, 2018Co-Authors: Mehdi Tazi, Madani Hedidi, William Erb, Yury S. Halauko, Oleg A. Ivashkevich, Vadim E. Matulis, Thierry Roisnel, Vincent Dorcet, Ghenia Bentabed-ababsa, Florence MonginAbstract:The ferrocene halogen "dance" has been deemed hardly controllable. Here, we describe the first efficient examples of this reaction. Conversion of 1-fluoro-2-iodo (or 1-chloro-2-iodo) to 1-fluoro-3-iodo (or 1-chloro-3-iodo) Ferrocenes was ensured by suitably protecting the free 5 position.
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Fluoro- and Chloroferrocene: From 2- to 3‑Substituted Derivatives
2018Co-Authors: Mehdi Tazi, Madani Hedidi, William Erb, Yury S. Halauko, Oleg A. Ivashkevich, Vadim E. Matulis, Thierry Roisnel, Vincent Dorcet, Ghenia Bentabed-ababsa, Florence MonginAbstract:The ferrocene halogen “dance” has been deemed hardly controllable. Here, we describe the first efficient examples of this reaction. Conversion of 1-fluoro-2-iodo (or 1-chloro-2-iodo) to 1-fluoro-3-iodo (or 1-chloro-3-iodo) Ferrocenes was ensured by suitably protecting the free 5-position
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From 2-to 3-Substituted Ferrocene Carboxamides or How to Apply Halogen "Dance" to the Ferrocene Series
Organometallics, 2017Co-Authors: Mehdi Tazi, William Erb, Yury S. Halauko, Oleg A. Ivashkevich, Vadim E. Matulis, Thierry Roisnel, Vincent Dorcet, Florence MonginAbstract:Two methods were compared to convert ferrocene into N,N-diisopropylferrocenecarboxamide, N,N-diethylferrocenecarboxamide, N,N-dimethylferrocenecarboxamide, and (4-morphohnocarbonyl)ferrocene, namely, deprotometalation followed by trapping using dialkylcarbamoyl chlorides and amide formation from the intermediate carboxylic acid. The four ferrocene-carboxamides were functionalized at C-2; in the case of the less hindered and more sensitive amides, recourse to a mixed lithium-zinc 2,2,6,6-tetramethylpiperidino-based base allowed us to "achieve the reactions. Halogen migration using lithium amides was next optimized. Whereas it appeared impossible to isolate the less hindered 3-iodoferrocenecarboxamides, 3-iodo-N,N-diisopropylferrocenecarboxamide proved stable and was converted to new 1,3-disubstituted Ferrocenes by Suzuki coupling or amide reduction. DFT calculations were used to rationalize the results obtained.
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From 2- to 3‑Substituted Ferrocene Carboxamides or How to Apply Halogen “Dance” to the Ferrocene Series
2017Co-Authors: Mehdi Tazi, William Erb, Yury S. Halauko, Oleg A. Ivashkevich, Vadim E. Matulis, Thierry Roisnel, Vincent Dorcet, Florence MonginAbstract:Two methods were compared to convert ferrocene into N,N-diisopropylferrocenecarboxamide, N,N-diethylferrocenecarboxamide, N,N-dimethylferrocenecarboxamide, and (4-morpholinocarbonyl)ferrocene, namely, deprotometalation followed by trapping using dialkylcarbamoyl chlorides and amide formation from the intermediate carboxylic acid. The four ferrocenecarboxamides were functionalized at C2; in the case of the less hindered and more sensitive amides, recourse to a mixed lithium–zinc 2,2,6,6-tetramethylpiperidino-based base allowed us to achieve the reactions. Halogen migration using lithium amides was next optimized. Whereas it appeared impossible to isolate the less hindered 3-iodoferrocenecarboxamides, 3-iodo-N,N-diisopropylferrocenecarboxamide proved stable and was converted to new 1,3-disubstituted Ferrocenes by Suzuki coupling or amide reduction. DFT calculations were used to rationalize the results obtained
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Synthesis of ferrocene amides and esters from aminoferrocene and 2-substituted ferrocenecarboxylic acid and properties thereof
New Journal of Chemistry, 2016Co-Authors: Palabindela Srinivas, Viatcheslav Jouikov, William Erb, Vincent Dorcet, Sunchu Prabhakar, Floris Chevallier, Ekhlass Nassar, Palakodety Radha Krishna, Florence MonginAbstract:Different ferrocenecarboxamides were synthesized from aminoferrocene and various acid coupling partners such as N-alpha-Boc-L-tryptophan and N-protected sugar amino acids ( N-Boc-3-amino-3-deoxy-1,2-O-isopropylidene-alpha-D-ribofuranoic acid, N-Boc-3-amino-3-deoxy-1,2-O-isopropylidene-alpha-D-xylofuranoic acid and their corresponding homo- and hetero-dimers). Similarly, reactions between 2-aminoethyl ferrocenecarboxylate and N-protected sugar amino acids afforded compounds with a carboxamide functional group remotely positioned from the ferrocene core. The X-ray diffraction structure of one of them showed the presence of an intermolecular hydrogen bond between the amide functional groups. Carbonylamino ( or carbonyloxy) and oxycarbonyl 1,2-disubstituted Ferrocenes were prepared either as racemic mixtures or in enantiomerically pure ( S-P) form. Their electrochemical evaluation revealed distinctive features. Interestingly, the enantiomerically pure ferrocene diester showed a large potential shift (+45 mV) in the presence of L-glutamic acid. Finally, some of the synthesized Ferrocenes were evaluated for their antibacterial, antifungal and antiproliferative ( MCF-7) activities.
Toshikazu Hirao - One of the best experts on this subject based on the ideXlab platform.
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intramolecular conformational control in Ferrocenes bearing podand dipeptide chains
Organometallics, 2001Co-Authors: Toshiyuki Moriuchi, Akihiro Nomoto, And Kazuhiro Yoshida, Toshikazu HiraoAbstract:Ferrocenes bearing podand dipeptide chains were demonstrated to induce intramolecular conformational regulation through hydrogen bondings. The single-crystal X-ray structure determination of the ferrocene bearing the podand dipeptide chains -Gly-l-Pro-OEt confirmed the formation of two intramolecular interchain hydrogen bondings between CO (Gly) and NH (another Gly) of each podand dipeptide chain (N(1)···O(102), 2.910 A; N(101)···O(2), 2.898 A; N(201)···O(302), 2.85 A; N(301)···O(202), 2.87 A) to give a 10-membered hydrogen-bonded ring. The ferrocene bearing the podand dipeptide chains -l-Pro-Gly-OEt is also considered to form two rigid intramolecular interchain hydrogen bondings between CO (bridging) and NH (another Gly) to give a 14-membered hydrogen-bonded ring. Such an ordered conformation was supported by the induced circular dichroism. On the other hand, the ferrocene bearing one dipeptide chain -Gly-l-Pro-OEt is packed in a helically ordered arrangement with one turn of 15.65 A pitch height through...
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chirality organization of Ferrocenes bearing podand dipeptide chains synthesis and structural characterization
Journal of the American Chemical Society, 2001Co-Authors: Toshiyuki Moriuchi, Akihiro Nomoto, Kazuhiro Yoshida, And Akiya Ogawa, Toshikazu HiraoAbstract:A variety of Ferrocenes bearing podand dipeptide chains have been synthesized to form an ordered structure in both solid and solution states and have been investigated by 1H NMR, FT-IR, CD, and X-ray crystallographic analyses. Conformational enantiomerization through chirality organization was achieved by the intramolecular hydrogen bondings between the podand dipeptide chains. The single-crystal X-ray structure determination of the ferrocene 2 bearing the podand dipeptide chains (-d-Ala-d-Pro-OEt) revealed two C2-symmetric intramolecular hydrogen bondings between CO (Ala) and NH (another Ala) of each podand dipeptide chain to induce the chirality-organized structure. The molecular structures of the ferrocene 1 composed of the podand l-dipeptide chains (-l-Ala-l-Pro-OEt) and 2 are in a good mirror image relationship, indicating that they are conformational enantiomers. An opposite helically ordered molecular arrangement was formed in the crystal packing of 2 as compared with 1. The ferrocene 2 exhibited i...