Asymmetric synthesis of chrysanthemic acid. An application of copper carbenoid reaction

Aratani, Tadatoshi; Yoneyoshi, Yukio; Nagase, Tsuneyuki

doi:10.1016/s0040-4039(01)83830-2

Cited by 121 publications

(28 citation statements)

References 8 publications

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“…Firstly, it is noteworthy that this kind of catalyst is different from the previous chiral copper catalysts in that the ee's for the cis isomer are higher than those for the trans isomer for the cyclopropanation of styrene. [2][3][4][5]. Substitution of the parahydrogen atom in catalyst 1a with electron-withdrawing substituents, such as a nitro group or a chlorine atom, resulted in an increase of the yield and ee of both trans and cis isomers (entries 6, 8 and 10).…”

Section: Resultsmentioning

confidence: 99%

“…Among the efficient catalysts which have been developed, copper-Schiff base complexes derived from chiral amino alcohols are of particular significance because they are effective for the intermolecular cyclopropanation of various substituted olefins including mono-, di-, and trisubstituted olefins, as well as for intramolecular cyclopropanation. [3][4][5][6][7][8] The successful industrial application of this kind of catalysts in the synthesis of chiral 2,2-dimethylcyclopropanecarboxylic acid makes it a significant achievement in asymmetric catalysis. 9 Even though it has received so much attention, to our knowledge, modification of this kind of catalyst to obtain higher enantioselectivity had only focused on the modification of chiral amino alcohols until 1999, Cai reported that copper-Schiff base complexes derived from 2-hydroxyl-5-methyl-1,3-benzenebisaldehyde were used as the catalyst.…”

Section: Introductionmentioning

confidence: 99%

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Asymmetric Cyclopropanation of Styrene Catalyzed by Cu–(Chiral Schiff-Base) Complexes

Liu

Zheng

et al. 2000

Tetrahedron

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Section: Resultsmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Asymmetric Cyclopropanation of Styrene Catalyzed by Cu–(Chiral Schiff-Base) Complexes

Liu

Zheng

et al. 2000

Tetrahedron

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“…The influence of the olefin is the weakest, while the electronic influence of the transition metal provides the dominant regio-and stereochemical control. Studies with chiral catalysts confirmed (21)(22)(23)(24) that the transition metal is directly involved in the product-forming step. The more stable trans cyclopropanes usually predominate and the stereoselecCan.…”

Section: Discussionmentioning

confidence: 92%

Dihydrofurans from α-diazoketones due to facile ring opening – cyclization of donor–acceptor cyclopropane intermediates

Lund¹,

Kennedy²,

Fallis³

1996

Can. J. Chem.

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A series of a-diazoketones, 8, 25,28,31, and 34, have been synthesized and their reaction with ethyl vinyl ether examined under various reaction conditions. In the presence of metal salts (Rh,(OAc),, Pd(OAc),, CuC1) the ethoxydihydrofurans 12,37,39,41, and 43 are produced. Sensitized irradiation of the a-diazoketone 8 afforded the dihydrofuran 12 plus cyclobutanone 7, while direct photolysis of a-diazoketones 8,25,28,31, and 34 gave the cyclobutanones 7,38,40,42, and 44, respectively. A sample of the cyclopropylketone 45 was isolated from the rhodium(I1) acetate mediated reaction of 34 and its facile rearrangement to dihydrofuran 43 demonstrated. Collectively, these results indicate that the initial product from the reaction of an a-diazoketone with an electron-rich alkene such as ethyl vinyl ether is a cyclopropylketone. The donnor-acceptor substitution pattern of this intermediate results in spontaneous rearrangement to a dihydrofuran. Thus a direct dipolar cycloaddition mechanism is not involved when a-diazoketones react with en01 ethers under metal-mediated conditions. Instead, these reactions follow a cyclopropanation rearrangement or, more accurately, cyclopropanation -ring opening -cyclization pathway.Key words: diazoketone, rhodium acetate, dihydrofuran, cyclopropylketone, vinyl ether.RCsumC : On a synthttist une strie d'a-diazocttones 8,25,28,31 et 34 et on a ttudit, dans difftrentes conditions, leur rtaction avec l'tther tthylvinylique. En prtsence de sels mttalliques (RH,(OAc),, Pd(OAC),, CuC1) on obtient les tthoxydihydrofurannes 12,37,39,41 et 43. L'irradiation sensibiliste de l'a-diazocttones 8 produit le dihydrofuranne 12 et la cyclobutanone 7, tandis que la photolyse directe des a-diazocttones 8,25,28,31 et 34 donne les cyclobutanones 7,38,40,42 et 44 respectivement. On a isolt un tchantillon de cyclopropylcttone 45 de la rtaction du compost 34 en prtsence de l'acttate de rhodium et on dtmontre sa transposition facile en dihydrofuranne 43. Collectivement, ces rtsultats indiquent que le produit initial de la rtaction d'une a-diazocttone avec un alcbne riche en tlectrons tel l'tther Cthylvinylique est une cyclopropylcttone. Le modble de substitution donneur-accepteur de cet intermtdiaire provient d'une transposition spontante en dihydrofuranne. Ainsi un mCcanisme de cycloaddition dipolaire directe n'est pas impliqut lorsque une a-diazocttone rtagit avec des tthers tnoliques en prtsence d'un mCtal. Au lieu de cela ces rtactions suivent une transposition cyclopropanique ou plus prtcistment un processus de cyclopropanation, d'ouverture du cycle du cyclopropane et de cyclisation.Mots cle's : diazocttone, acttate de rhodium, dihydrofuranne, cyclopropylcCtone, tther vinylique.[Traduit par la rtdaction]

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“…Katalysatoren dieses Typs waren zuerst von Aratani et al [61 Um die Enantiomerenuberschiisse der beiden Cyclopropandiastereomere zu bestimmen, wurde das Isomerengemisch in Deuteriobenzol gelost und rnit unterschiedlichen Mengen Tris [3-(2,2,3,3,4,4,4-heptafluor-I -hydroxybutyliden Das in Versuch 10 erhaltene Diastereomerengemisch von 3a wurde chromatographisch getrennt, und die beiden Cyclopropanisomere wurden jeweils mit Bu4NF. 3 H 2 0 in den y-Oxocarbonsaureester 6a ubergefuhrt.…”

Section: Darstellung Der Chiralen Katalysatorligandenunclassified

Synthese optisch aktiver 2‐Siloxycyclopropancarbonsäureester durch asymmetrische Katalyse, I. Katalysatoreinfluß auf die Cyclopropanierung von (Z)‐1‐Phenyl‐1‐(trimethylsiloxy)prop‐1‐en

Dammast

Reißig

1993

Chem. Ber.

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Synthesis of Optically Active Siloxycyclopropanes by Asymmetric Catalysis, I. -Influence of the Catalyst on the Cyclopropanation of (3-1-Phenyl-1-(trimethylsi1oxy)prop-1-eneThe cyclopropanation of silyl enol ether l a with methyl diazo-propanations of silyl enol ethers with easily available copperacetate (2a) and diazoesters 2b-d in the presence of optically Schiff base catalysts. The ring opening of the separated diaactive copper salicylimine complexes 4-Cu was systematically stereomers of 3a employing nBu,NF provided methyl y-oxostudied. Up to 88% enantiomeric excess in products 3 were carboxylate 6a in good optical purity. This demonstrates that obtained by employing the appropriate reaction conditions this process occurs without racemization and also that 3a is and the optimal catalyst ligands. Thus, for the first time re-formed with the same absolute configuration at C-1. spectable optical yields were achieved in asymmetric cycloDurch ifbergangsmetall-katalysierte Carben-Addition an Silylenolether A mit Diazoessigsaureestern B lassen sich vielfaltig substituierte 2-Siloxycyclopropancarbonsaureester

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Asymmetric synthesis of chrysanthemic acid. An application of copper carbenoid reaction

Cited by 121 publications

References 8 publications

Asymmetric Cyclopropanation of Styrene Catalyzed by Cu–(Chiral Schiff-Base) Complexes

Asymmetric Cyclopropanation of Styrene Catalyzed by Cu–(Chiral Schiff-Base) Complexes

Dihydrofurans from α-diazoketones due to facile ring opening – cyclization of donor–acceptor cyclopropane intermediates

Synthese optisch aktiver 2‐Siloxycyclopropancarbonsäureester durch asymmetrische Katalyse, I. Katalysatoreinfluß auf die Cyclopropanierung von (Z)‐1‐Phenyl‐1‐(trimethylsiloxy)prop‐1‐en

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