Relevant bibliographies by topics / Asymmetric synthesis. Ring formation (Chemistry)

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  1. Journal articles
  2. Dissertations / Theses
  3. Books
  4. Book chapters
  5. Conference papers

Academic literature on the topic 'Asymmetric synthesis. Ring formation (Chemistry)'

Author: Grafiati
Published: 4 June 2021
Last updated: 8 February 2022

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Journal articles on the topic "Asymmetric synthesis. Ring formation (Chemistry)"

1

Pellissier, Hélène. "The Use of Domino Reactions for the Synthesis of Chiral Rings." Synthesis 52, no. 24 (2020): 3837–54. http://dx.doi.org/10.1055/s-0040-1707905.

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This short review highlights the recent developments reported in the last four years on the asymmetric construction of chiral rings based on enantioselective domino reactions promoted by chiral metal catalysts.1 Introduction2 Formation of One Ring Containing One Nitrogen Atom3 Formation of One Ring Containing One Oxygen/Sulfur Atom4 Formation of One Ring Containing Several Heterocyclic Atoms5 Formation of One Carbon Ring6 Formation of Two Rings7 Conclusion
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2

Ndoile, Monica M., and Fanie R. van Heerden. "Total synthesis of ochnaflavone." Beilstein Journal of Organic Chemistry 9 (July 8, 2013): 1346–51. http://dx.doi.org/10.3762/bjoc.9.152.

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The first total syntheses of ochnaflavone, an asymmetric biflavone consisting of apigenin and luteolin moieties, and the permethyl ether of 2,3,2'',3''-tetrahydroochnaflavone have been achieved. The key steps in the synthesis of ochnaflavone were the formation of a diaryl ether and ring cyclization of an ether-linked dimeric chalcone to assemble the two flavone nuclei. Optimal experimental conditions for the oxidative cyclization to form ochnaflavone were established.
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Williams, David R., and Joseph R. Pinchman. "Studies of neodolastanes — Synthesis of the tricyclic core of the trichoaurantianolides." Canadian Journal of Chemistry 91, no. 1 (2013): 21–37. http://dx.doi.org/10.1139/v2012-088.

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Studies toward the synthesis of trichoaurantianolide C (5) are described. Stille cross-coupling reactions of (E)- and (Z)-β-stannyl-α,β-unsaturated esters with allylic acetate 32 provide for the stereocontrolled formation of nonconjugated 2,5-diene-1-ols. Studies of the asymmetric Sharpless epoxidation are utilized to establish diastereofacial selectivity for the preparation of a crucial C2 tertiary allylic alcohol for subsequent esterification and ring-closing metathesis. SmI2 reductive cyclization of the key butenolide precursor 49 led to formation of the central seven-membered ring of the t
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Frontier, Alison, Peter Carlsen, and Eric Stoutenburg. "SYNTHESIS–SYNLETT Lecture: Toward the Asymmetric Synthesis of Tetrapetalone A: Preparation of an Enantioenriched Indane Intermediate and Strategy for Endgame Glycosylation." Synthesis 50, no. 06 (2018): 1238–45. http://dx.doi.org/10.1055/s-0036-1591747.

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A chiral auxiliary is employed to obtain, via Nazarov cyclization, a synthetic intermediate crucial to our previously reported synthesis of the tetrapetalone A core. This indane derivative, corresponding to the A and B rings of the tetrapetalone natural product skeleton, is then used to test an endgame strategy for installation of the β-rhodinosyl group on ring B. A palladium-catalyzed decarboxylative coupling is described that effects the exclusive formation of the desired β-glycosidic linkage, and the target rhodinose moiety can be obtained via hydrogenation.
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Hoover, Gabrielle C., Jennifer Ham, Connie Tang, Elisa I. Carrera, and Dwight S. Seferos. "Synthesis and self-assembly of thiol-modified tellurophenes." Canadian Journal of Chemistry 96, no. 10 (2018): 929–33. http://dx.doi.org/10.1139/cjc-2018-0077.

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An asymmetric thiol-modified tellurophene was designed and synthesized, and the ability of the compound to form a monolayer on a gold electrode was confirmed. The surface-active tellurophene was synthesized using Cadiot–Chodkiewicz coupling followed by ring closing and thiol modification. The tellurophene compound forms a monolayer on gold surfaces from a concentrated solution within 24 h. The ability of the compound to conjugate to gold is confirmed by X-ray photoelectron spectroscopy (XPS). A surface blocking experiment was used to evaluate the extent of formation of a monolayer on a gold el
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Hauer, Bernhard, Jamie F. Bickley, Julien Massue, Paula CA Pena, Stanley M. Roberts, and John Skidmore. "Biomimetic reactions in organic synthesis: Semi-pinacol rearrangements of some spirocyclic epoxyalcohols derived from Juliá-Colonna asymmetric epoxidations." Canadian Journal of Chemistry 80, no. 6 (2002): 546–50. http://dx.doi.org/10.1139/v02-061.

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Epoxy tert-alcohols have been prepared from (E)-enones in a two-step approach consisting of Juliá–Colonna asymmetric epoxidation followed by Grignard alkylation of the epoxyketone. On treatment with sub-stoichiometric amounts of Yb(OTf)3 these trans-epoxyalcohols underwent efficient stereoselective semi-pinacol rearrangement to afford anti-α-phenyl-β-hydroxy-ketones (aldols). Under the same conditions, spirocyclic epoxyalcohols derived from 1-tetralone and 1-benzosuberone undergo either ring contraction (via semi-pinacol rearrangement) or fragmentation. A mechanistic rationale is presented to
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7

Salgado, Mateo M., Alejandro Manchado, Carlos T. Nieto, David Díez, and Narciso M. Garrido. "Synthesis and Modeling of Ezetimibe Analogues." Molecules 26, no. 11 (2021): 3107. http://dx.doi.org/10.3390/molecules26113107.

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Ezetimibe is a well-known drug that lowers blood cholesterol levels by reducing its absorption in the small intestine when joining to Niemann-Pick C1-like protein (NPC1L1). A ligand-based study on ezetimibe analogues is reported, together with one-hit synthesis, highlighted in the study. A convenient asymmetric synthesis of (2S,3S)-N-α-(R)-methylbenzyl-3-methoxycarbonylethyl-4-methoxyphenyl β-lactam is described starting from Baylis–Hillman adducts. The route involves a domino process: allylic acetate rearrangement, stereoselective Ireland–Claisen rearrangement and asymmetric Michael addition,
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8

Wipf, Peter, and Michel Grenon. "Toward the total synthesis of lophotoxin — New methodologies and synthetic strategies." Canadian Journal of Chemistry 84, no. 10 (2006): 1226–41. http://dx.doi.org/10.1139/v06-073.

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Our recent progress toward the synthesis of the furanocembranolide lophotoxin (1) is disclosed. Strategies for the stereoselective incorporation of the C13 stereocenter by a catalytic desymmetrization of a cyclic meso-anhydride, as well as a novel 1,6-addition reaction of organocuprates to unsaturated [1,3]dioxin-4-ones are discussed. Preliminary results on the development of a rhodium-catalyzed asymmetric 1,6-addition reaction are also mentioned. Finally, modifications of a previously reported transition-metal-catalyzed cyclization reaction involving α-propargyl β-keto esters allow furan ring
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9

Martinez-Cuezva, Alberto, Carmen Lopez-Leonardo, Mateo Alajarin та Jose Berna. "Stereocontrol in the Synthesis of β-Lactams Arising from the Interlocked Structure of Benzylfumaramide-Based Hydrogen-Bonded [2]Rotaxanes". Synlett 30, № 08 (2019): 893–902. http://dx.doi.org/10.1055/s-0037-1611705.

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β-Lactams are highly valuable compounds due to their antibiotic activity. Among the number of well-established methodologies for building this privileged scaffold, our research group has settled on a novel synthetic approach for their preparation. This Account focuses on our latest progress in the synthesis of these compounds through a novel base-promoted intramolecular cyclization of benzylfumaramide-based rotaxanes. The mechanical bond plays a significant role in the process by activating the cyclization inside the macrocycle void, avoiding the formation of byproducts and fully controlling t
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Sun, Yin-wei, Qin Xu, and Min Shi. "Synthesis of axially chiral gold complexes and their applications in asymmetric catalyses." Beilstein Journal of Organic Chemistry 9 (October 28, 2013): 2224–32. http://dx.doi.org/10.3762/bjoc.9.261.

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Several novel chiral N-heterocyclic carbene and phosphine ligands were prepared from (S)-BINOL. Moreover, their ligated Au complexes were also successfully synthesized and characterized by X-ray crystal diffraction. A weak gold-π interaction between the Au atom and the aromatic ring in these gold complexes was identified. Furthermore, we confirmed the formation of a pair of diastereomeric isomers in NHC gold complexes bearing an axially chiral binaphthyl moiety derived from the hindered rotation around C–C and C–N bonds. In the asymmetric intramolecular hydroamination reaction most of these ch
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Dissertations / Theses on the topic "Asymmetric synthesis. Ring formation (Chemistry)"

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Rane, Digamber Sadanand. "Acyl Imidazole : A Promising Template for Asymmetric Lewis and Br?nsted Acid Mediated 1,3-Dipolar Cycloadditions." Diss., North Dakota State University, 2011. https://hdl.handle.net/10365/29336.

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Construction of chiral complex molecules continues to be a challenge for organic chemists all over the world and to address this challenge numerous methodologies have been developed. 1,3-Dipolar cycloaddition reactions is one such simple and elegant method, which can be employed towards the construction of chiral heterocycles. The ability to construct multiple stereocenters in one operation is one of the salient features of dipolar cycloaddition reaction. Asymmetric dipolar cycloaddition via chiral Lewis or Bronsted acid catalyzed processes is aided by the development of various templates, whi
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Rane, Digamber Sadanand. "Acyl Imidazole : A Promising Template for Asymmetric Lewis and Brønsted Acid Mediated 1,3-Dipolar Cycloadditions." Diss., North Dakota State University, 2011. https://hdl.handle.net/10365/29336.

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Construction of chiral complex molecules continues to be a challenge for organic chemists all over the world and to address this challenge numerous methodologies have been developed. 1,3-Dipolar cycloaddition reactions is one such simple and elegant method, which can be employed towards the construction of chiral heterocycles. The ability to construct multiple stereocenters in one operation is one of the salient features of dipolar cycloaddition reaction. Asymmetric dipolar cycloaddition via chiral Lewis or Bronsted acid catalyzed processes is aided by the development of various templates, whi
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Lam, Sze-kui. "An asymmetric carbene cyclization cycloaddition strategy toward the synthesis of indicol." Click to view the E-thesis via HKUTO, 2005. http://sunzi.lib.hku.hk/hkuto/record/B36631863.

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Lam, Sze-kui, and 林詩鉅. "An asymmetric carbene cyclization cycloaddition strategy toward the synthesis of indicol." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B36631863.

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Power, Lynn A. "New synthetic uses for chiral 1,3-dioxolan-4-ones." Thesis, St Andrews, 2008. http://hdl.handle.net/10023/548.

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Ho, Chun-yu. "Asymmetric epoxidation of olefins and cyclization reactions catalyzed by amines /." View the Table of Contents & Abstract, 2005. http://sunzi.lib.hku.hk/hkuto/record/B31490682.

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Ho, Chun-yu, and 何振宇. "Asymmetric epoxidation of olefins and cyclization reactions catalyzed by amines." Thesis, The University of Hong Kong (Pokfulam, Hong Kong), 2005. http://hub.hku.hk/bib/B45014814.

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Zhong, Hua Marlon. "I. Formation of Medium-Sized Rings Via (Beta)-Scission of Alkoxy Radicals. II. One-Step Conversion of Esters to Acyl Azides using Et2AIN3. III. Studies on Asymmetric Synthesis of the Right Part of Mycalamides and Related Compounds /." The Ohio State University, 1995. http://rave.ohiolink.edu/etdc/view?acc_num=osu148792923074158.

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Snell, Robert Henry. "Development and application of asymmetric C-N bond formation." Thesis, University of Oxford, 2011. http://ora.ox.ac.uk/objects/uuid:512e617a-2b01-45f3-86ae-c0cf4b874149.

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A synthetic investigation on the chemistry of cyclotryptamine derived natural products, with a particular focus on the synthesis of the trimeric-alkaloid, hodgkinsine. Methodology has been developed to tackle this complex natural product which utilises a desymmetrization approach; this strategy hinges on the development and applications of asymmetric C-N bond forming reactions. Chapter one examines elements of symmetry in natural products, looking in particular at the synthesis of compounds which contain cyclotryptamine functionality. Chapter two contains a brief review of enantioselective des
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Sengpracha, Waya. "Synthesis of biologically active indole-fused heterocyclic derivatives." Department of Chemistry - Faculty of Science, 2005. http://ro.uow.edu.au/theses/279.

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New synthetic routes to 1,2- and 2,3-fused indoles with seven- or eight-membered rings have been developed in this project, with the longer term aim of assessing their biological activity. Approaches to such fused indole derivatives were accessed via free radical cyclisation from 1- or 2-substituted indole derivatives with haloacetamide precursors. Using 1-substituted indole derivatives with haloacetamide functionalites, free radical cyclisation reactions gave fair yields of the indole- and dihydroindole-fused eight membered ring derivatives. Using 2-substituted indole derivatives with haloace
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Books on the topic "Asymmetric synthesis. Ring formation (Chemistry)"

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Byrne, Maeve. The synthesis and cyclisation of 2-bromo-3-ethoxypropanones. University College Dublin, 1998.

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2

Carbocycle construction in terpene synthesis. VCH, 1988.

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Boger, Dale L. Hetero Diels-Alder methodology inorganic synthesis. Academic Press, 1987.

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Boger, Dale L. Hetero Diels-Alder methodology in organic synthesis. Academic Press, 1987.

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5

Zadrożna, Irmina. Modyfikacja struktury wybranych układów cyklicznych i policyklicznych w celu uzyskania odpowiednich właściwości optycznych, fotochemicznych i biologicznych. Oficyna Wydawnicza PW, 2001.

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Joseph Johannes Gerardus Steven van Es. 1, 3-cycloaddition reactions of diphenylphosphinoyl-activated azomethine ylides and 2-azaallyl anions: Synthetic applications and mechanistic aspects. Pasmans Offsetdrukkerij BV, 1992.

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Horst, Kunz, ed. Chiral auxiliaries in cycloadditions. Wiley-VCH, 1999.

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Science of synthesis: Stereoselective synthesis : Stereoselective reactions of carbonal and imino groups. Georg Thieme, 2011.

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Maier, Martin. Hetero-Diels-Alder Reaktionen mit inversem Elektronenbedarf zur Synthese von Hexopyranosiden. Hartung-Gorre, 1985.

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Wolfe, J. P. (James Philip), 1943- and Larhed Mats, eds. Science of synthesis: Cross coupling and Heck-type reactions. Georg Thieme Verlag KG, 2013.

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Book chapters on the topic "Asymmetric synthesis. Ring formation (Chemistry)"

1

Nielsen, Lars P. C., and Eric N. Jacobsen. "Catalytic Asymmetric Epoxide Ring-opening Chemistry." In Aziridines and Epoxides in Organic Synthesis. Wiley-VCH Verlag GmbH & Co. KGaA, 2006. http://dx.doi.org/10.1002/3527607862.ch7.

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Fessner, Wolf-Dieter, and Christiane Walter. "Enzymatic C-C bond formation in asymmetric synthesis." In Topics in Current Chemistry. Springer Berlin Heidelberg, 1996. http://dx.doi.org/10.1007/3-540-61388-9_63.

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Shibasaki, Masakatsu, and Harald Gröger. "Chiral Heterobimetallic Lanthanoid Complexes: Highly Efficient Multifunctional Catalysts for the Asymmetric Formation of C-C, C-O, and C-P Bonds." In Lanthanides: Chemistry and Use in Organic Synthesis. Springer Berlin Heidelberg, 1999. http://dx.doi.org/10.1007/3-540-69801-9_5.

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Lambert, Tristan H. "Total Synthesis of C–O Ring-Containing Natural Products." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0053.

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Scott A. Snyder at Columbia University demonstrated (J. Am. Chem. Soc. 2012, 134, 17714) that tetrahydrofuran 1 could be readily converted to oxocane 2 by treatment with the BDSB reagent developed in his laboratory. Reduction of 2 with DIBAL-H initiated a second ring closure by mesylate displacement to form the bicycle 3, which represented a formal total synthesis of laurefucin 4. Andrew L. Lawrence at the Australian National University found (Org. Lett. 2012, 14, 4537) that upon treatment with catalytic base, rengyolone 6, which was prepared in one pot from phenol 5, could be converted to the natural products incarviditone 7 and incarvilleatone 8. This demonstration provides strong support for the postulated biomimetic formation of these natural products. Shuanhu Gao at East China Normal University reported (Angew. Chem. Int. Ed. 2012, 51, 7786) the total synthesis of (+)-fusarisetin A 12 via biomimetic oxidation of equisetin 10 to produce the peroxy compound 11, followed by reduction. The bicyclic carbon skeleton of equisetin 10 was synthesized by intramolecular Diels-Alder reaction of trienyl aldehyde 9. The ellagitannin natural product (+)-davidiin 15 possesses a glucopyranose core with the unusual 1C4 (tetraaxial) conformation due to the presence of a biaryl bridge between two of the galloyl groups. Hidetoshi Yamada at Kwansei Gakuin University constructed (Angew. Chem. Int. Ed. 2012, 51, 8026) this bridge by oxidation with CuCl2 of 13, in which the three sterically demanding triisopropylsiloxy groups enforce the requisite tetraaxial conformation. John A. Porco, Jr. at Boston University applied (J. Am. Chem. Soc. 2012, 134, 13108) his asymmetric [3+2] photocycloaddition chemistry to the total synthesis of the aglain natural product (+)-ponapensin 20. Irradiation of hydroxyflavone 16 with methyl cinnamate 17 in the presence of diol 18 afforded the entire core framework 19 of ponapensin 20, which was accessed in just a few further synthetic transformations. Finally, Silas P. Cook at Indiana University reported (J. Am. Chem. Soc. 2012, 134,13577) a five-pot total synthesis of the antimalarial (+)-artemisinin 25. Cyclohexenone 21 was converted by simple operations to aldehyde 22. This aldehyde was then engaged in a [4+2] cycloaddition with the silyl ketene acetal 23 to produce, after an impressive Wacker oxidation of the disubstituted olefin, bicycle 24.
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Lambert, Tristan H. "C–O Ring Formation." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0044.

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The enantioselective bromocyclization of dicarbonyl 1 to form dihydrofuran 3 using thiocarbamate catalyst 2 was developed (Angew. Chem. Int. Ed. 2013, 52, 8597) by Ying-Yeung Yeung at the National University of Singapore. Access to dihydrofuran 5 from the cyclic boronic acid 4 and salicylaldehyde via a morpholine-mediated Petasis borono-Mannich reaction was reported (Org. Lett. 2013, 15, 5944) by Xian-Jin Yang at East China University of Science and Technology and Jun Yang at the Shanghai Institute of Organic Chemistry. Chiral phosphoric acid 7 was shown (Angew. Chem. Int. Ed. 2013, 52, 13593) by Jianwei Sun at the Hong Kong University of Science and Technology to catalyze the enantioselective acetalization of diol 6 to form tetrahydrofuran 8 with high stereoselectivity. Jan Deska at the University of Cologne reported (Org. Lett. 2013, 15, 5998) the conversion of glutarate ether 9 to enantiopure tetrahy­drofuranone 10 by way of an enzymatic desymmetrization/oxonium ylide rearrange­ment sequence. Perali Ramu Sridhar at the University of Hyderabad demonstrated (Org. Lett. 2013, 15, 4474) the ring-contraction of spirocyclopropane tetrahydropyran 11 to produce tetrahydrofuran 12. Michael A. Kerr at the University of Western Ontario reported (Org. Lett. 2013, 15, 4838) that cyclopropane hemimalonate 13 underwent conver­sion to vinylbutanolide 14 in the presence of LiCl and Me₃N•HCl under microwave irradiation. Eric M. Ferreira at Colorado State University developed (J. Am. Chem. Soc. 2013, 135, 17266) the platinum-catalyzed bisheterocyclization of alkyne diol 15 to fur­nish the bisheterocycle 16. Chiral sulfur ylides such as 17, which can be synthesized easily and cheaply, were shown (J. Am. Chem. Soc. 2013, 135, 11951) by Eoghan M. McGarrigle at the University of Bristol and University College Dublin and Varinder K. Aggarwal at the University of Bristol to stereoselectively epoxidize a variety of alde­hydes, as exemplified by 18. The amine 20-catalyzed tandem heteroconjugate addition/Michael reaction of quinol 19 and cinnamaldehyde to produce bicycle 21 with very high ee was reported (Chem. Sci. 2013, 4, 2828) by Jeffrey S. Johnson at the University of North Carolina, Chapel Hill. Quinol ether 22 underwent facile photorearrangement–cycloaddition to 23 under irradiation, as reported (J. Am. Chem. Soc. 2013, 135, 17978) by John A. Porco, Jr. at Boston University and Corey R. J. Stephenson, now at the University of Michigan.
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Taber, Douglass. "Stereoselective C-O Ring Construction: The Oguri-Oikawa Synthesis of Lasalocid A." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0047.

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O-Centered radicals have been little used for C-O ring formation. Glenn M. Sammis of the University of British Columbia showed (Organic Lett. 2008, 10, 5083) that O-centered radicals could be generated efficiently, and that they cyclized with high diasterecontrol. Liming Zhang of the University of Nevada, Reno, continuing his studies of Au-activation of alkynes, uncovered (J. Am. Chem. Soc. 2008, 130, 12598) the bimolecular condensation of polarized alkynes such as 3 with aldehydes and ketones, including 4, to give the dihydrofuran with high diastereocontrol. Margarita Brovetto of the Universidad de la República, Montevideo, Uruguay, prepared (J. Org. Chem. 2008, 73, 5776) the precursor to the enantiomercially triol 6 by fermentation of bromobenzene with Pseudomonas putida 39/D. Cyclization of 6 gave 7 with high diastereocontrol. Petri M. Pihko of the University of Jyväskylä, Finland, found (Organic Lett . 2008, 10, 4179) that cyclization of 8, prepared by Sharpless asymmetric epoxidation followed by Sharpless asymmetric dihydroxylation, also proceeded with high diastereocontrol. Vincent Aucagne of the Université d’Orléans observed (Tetrahedron Lett. 2008, 49, 4750) that brief exposure of the sulfone 10 to t -BuOK at low temperature gave clean conversion to the kinetic diastereomer 11. At room temperature, similar conditions delivered the other, more stable diastereomer. Angeles Martín and Ernesto Suárez of the C. S. I. C., La Laguna, took advantage (Tetrahedron Lett. 2008, 49, 5179) of the facile generation of O-centered radicals in converting 12 to 14, having a stereocontrolled quaternary center. The transformation is thought to be proceeding by H-atom abstraction, then diastereocontrolled trapping of the C-radical so formed with the allyl stannane 13. Much of the effort toward alkylated cyclic ether construction has been focused on alkyl group attachment adjacent to the ring oxygen. Torsten Linker of the University of Potsdam developed (J. Am. Chem. Soc. 2008, 130, 16003) a complementary approach, stereocontrolled oxidative radical addition of malonate 16 to glycals such as 15 to give the 3-alkyl substituted 17.
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Li, Jie Jack, Chris Limberakis, and Derek A. Pflum. "Carbon−Carbon Bond Formation." In Modern Organic Synthesis in the Laboratory. Oxford University Press, 2008. http://dx.doi.org/10.1093/oso/9780195187984.003.0011.

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Reviews: (a) Vicarion, J. L.; Badia, D.; Carillo, L.; Reyes, E.; Etxebarria, J. Curr. Org. Chem. 2005, 9, 219-235. (b) Mahrwald, R. Ed. In Modern Aldol Reactions; Wiley-VCH: Weinheim, 2004; Vol. 1., pp. 1-335 (c) Mahrwald, R. Ed. In Modern Aldol Reactions; Wiley-VCH: Weinheim, 2004; Vol. 2., pp. 1-345.(d) Machajewski, T. D.; Wong, C.-H. Angew. Chem. Int. Ed. 2000, 39, 1352-1375. (e) Carriera, E. M. In Modern Carbonyl Chemistry; Otera, J.; Wiley-VCH: Weinheim, 2000; Chapter 8: Aldol Reaction: Methodology and Stereochemistry, 227-248. (f) Paterson, I.; Cowden, C. J.; Wallace, D. J. In Modern Carbonyl Chemistry; Otera, J.; Wiley-VCH: Weinheim, 2000; Chapter 9: Stereoselective Aldol Reactions in the Synthesis of Polyketide Natural Products, pp. 249-298. (g) Franklin, A. S.; Paterson, I. Contemp. Org. Synth. 1994, 1 317-338. (h) Heathcock, C. H. In Asymmetric Synthesis; Morrison, J. D., Ed.; Academic Press: Orlando, Fl.; 1984; Vol. 3., Chapter 2: The Aldol Addition Reaction, pp. 111-212. (i) Mukaiyama, T. Org. React. 1982, 28, 203-331. Since the early 1980s, aldol condensations involving boron enolates have gain great importance in asymmetric synthesis, particularly the synthesis of natural products with adjacent stereogenic centers bearing hydroxyl and methyl groups. (Z)-Boron enolates tend to give a high diastereoslectivity preference for the syn-stereochemistry while (E)-boron enolates favor the anti-stereochemistry. Because the B-O and B-C bonds are shorter than other metals with oxygen and carbon, the six membered Zimmerman–Traxler transition state in the aldol condensation tends to be more compact which accentuates steric interactions, thus leading to higher diastereoselectivity. When this feature is coupled with a boron enolate bearing a chiral auxillary, high enantioselectivity is achieved. Boron enolates are generated from a ketone and boron triflate in the presence of an organic base such as triethylamine. Reviews: (a) Abiko, A. Acc. Chem. Res. 2004, 37, 387-395. (b) Cowden, C. J. Org. React. 1997, 51, 1-200.
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Taber, Douglass. "New Methods for C-N Ring Construction." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0055.

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Chaozhong Li of the Shanghai Institute of Organic Chemistry demonstrated (Organic Lett. 2008, 10, 4037) facile and selective Cu-catalyzed β-lactam formation, converting 1 to 2. Paul Helquist of the University of Notre Dame devised (Organic Lett. 2008, 10, 3903) an effective catalyst for intramolecular alkyne hydroamination, converting 3 into the imine 4. Six-membered ring construction worked well also. Jon T. Njardarson of Cornell University found (Organic Lett. 2008, 10, 5023) a Cu catalyst for the rearrangement of alkenyl aziridines such as 5 to the pyrroline 6. Philippe Karoyan of the UPMC, Paris developed (J. Org. Chem. 2008, 73, 6706) an interesting chiral auxiliary directed cascade process, converting the simple precursor 7 into the complex pyrrolidine 9. Sherry R. Chemler of the State University of New York, Buffalo devised (J. Am. Chem. Soc. 2008, 130, 17638) a chiral Cu catalyst for the cyclization of 10, to give 12 with substantial enantiocontrol. Wei Wang of the University of New Mexico demonstrated (Chem. Commun. 2008, 5636) the organocatalyzed condensation of 13 and 14 to give 16 with high enantio- and diastereocontrol. Two complementary routes to azepines/azepinones have appeared. F. Dean Toste of the University of California, Berkeley showed (J. Am. Chem. Soc. 2008, 130, 9244) that a gold complex catalyzed the condensation of 17 and 18 to give 19. Frederick G. West of the University of Alberta found (Organic Lett. 2008, 10, 3985) that lactams such as 20 could be ring-expanded by the addition of the propiolate anion 21. Takeo Kawabata of Kyoto University extended (Organic Lett . 2008, 10, 3883) “memory of chirality” studies to the cyclization of 23, demonstrating that 24 was formed in high ee. Paul V. Murphy of University College Dublin took advantage (Organic Lett . 2008, 10, 3777) of the well-known intramolecular addition of azides to alkenes, showing that the intermediate could be intercepted with nucleophiles such as thiophenol, to give the cyclized product 26 with high diastereocontrol.
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9

Taber, Douglass. "Transition Metal-Mediated C-C Ring Construction: The Stoltz Synthesis of (-)-Cyanthiwigin F." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0077.

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X. Peter Zhang of the University of South Florida extended (Organic Lett. 2009, 11, 2273) Co-catalyzed asymmetric cyclopropanation to the activated ester 2. The product 3 readily coupled with amines. André B. Charette of the Université de Montréal showed (J. Am. Chem. Soc. 2009, 131, 6970) that even α-olefins such as 4 could be cyclopropanated in high ee with the diazo amide 5. Xue-Long Hou of the Shanghai Institute of Organic Chemistry established (J. Am. Chem. Soc. 2009, 131, 8734) conditions for the enantioselective coupling of 7 and 8 to give 9 , in which sidechain chirality was also controlled. Tristan H. Lambert of Columbia University found (J. Am. Chem. Soc. 2009, 131, 7536) that “methylene” could be transferred in an intramolecular sense from the epoxide of 10 to the alkene, delivering the cyclopropane 11 in high ee. Yuichi Kobayashi of the Tokyo Institute of Technology established (Organic Lett . 2009, 11, 1103) that the 2-picolinoxy leaving group worked well for the SN2' coupling with 13 to give 14. Chang Ho Oh of Hanyang University developed (J. Org. Chem. 2009, 74, 370) a new route to cyclopentenones such as 16, by gold-catalyzed cyclization of diynes such as 15. David J. Procter of the University of Manchester used (J. Am. Chem. Soc. 2009, 131, 7214; Tetrahedron Lett . 2009, 50, 3224) SmI2 to cyclize 17 to 18 and 19 to 20, each with high diastereocontrol. Yoshiaki Nishibayashi of the University of Tokyo devised (Angew. Chem. Int. Ed. 2009, 48, 2534) Ru catalysts for the cyclization of an enyne such as 21 to the cyclohexadiene 22. Laurel L. Schafer of the University of British Columbia developed (J. Am. Chem. Soc. 2009, 131, 2116) a Zr catalyst for the diastereocontrolled cyclization of amino alkenes such as 23. Hongbin Zhai of the Shangahi Institute of Organic Chemistry showed (J. Org. Chem. 2009, 74, 2592) that the Mo-mediated cyclization of 25 also proceeded with high diastereocontrol. Even more impressive was the selectivity Kozo Shishido of the University of Tokushima demonstrated (Tetrahedron Lett . 2009, 50, 1279) for the cyclization of 27.
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10

Taber, Douglass F. "Organocatalytic C–C Ring Construction: Prostaglandin F2α (Aggarwal)." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0072.

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Marco Lombardo of the Università degli Studi di Bologna devised (Adv. Synth. Catal. 2012, 354, 3428) a silyl-bridged hydroxyproline catalyst that mediated the enantioselective addition of 2 to cinnamaldehyde 1 to give 3. Yoann Coquerel and Jean Rodriguez of Aix Marseille Université showed (Adv. Synth. Catal. 2012, 354, 3523) that a hybrid epi-cinchonine catalyst directed the enantioselective and diastereoselective addition of the amide 4 to the nitro alkene 5 to give 6. Magnus Rueping of RWTH Aachen observed (Angew. Chem. Int. Ed. 2012, 51, 12864) that a chiral Brønsted acid mediated the diastereoselective and enantioselective formation of 9 by the addition of 8 to cyclopentadiene 7. Marco Bandini, also of the University of Bologna, combined (Chem. Sci. 2012, 3, 2859) organocatalysis with gold catalysis to effect the cyclization of 10 to 11. Min Shi of the Shanghai Institute of Organic Chemistry prepared (Chem. Commun. 2012, 48, 2764) the quaternary cyclic amino acid derivative 14 by adding 13 to the acceptor 12. Makoto Tokunaga of Kyushu University prepared (Org. Lett. 2012, 14, 6178) the ketone 17 by the hydrolytic enantioselective protonation of the enol ester 15. Hiyoshizo Kotsuki of Kochi University developed (Synlett 2012, 23, 2554) a dual catalyst combination that effectively mediated the enantioselective addition of malonate even to the congested acceptor 18. Yoshitaka Hamashima and Toshiyuki Kan of the University of Shizuoka established (Org. Lett. 2012, 14, 6016) a protocol for the enantioselective brominative cyclization of 21, readily available by the reductive alkylation of benzoic acid. Polycarbocyclic ring systems can also be prepared by organocatalysis. Ying-Chun Chen of Sichuan University tuned (J. Am. Chem. Soc. 2012, 134, 19942) cinchona-derived catalysts to selectively convert 23 into either exo (illustrated) or endo 25. Peng-Fei Xu of Lanzhou University developed (Angew. Chem. Int. Ed. 2012, 51, 12339) a supramolecular iminium catalyst for the intramolecular Diels-Alder cycloaddition of 26. In a spectacular illustration of the power of organocatalysis, Varinder K. Aggarwal of the University of Bristol dimerized (Nature 2012, 489, 278) succinaldehyde from the hydrolysis of commercial 28 directly to the unsaturated aldehyde 29. Diastereoselective conjugate addition led to prostaglandin F2α 30.
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Conference papers on the topic "Asymmetric synthesis. Ring formation (Chemistry)"

1

DENIAU, Eric, and Stéphane LEBRUN. "Asymmetric photoinduced electrocyclic ring closure of chiral aromatic enehydrazides. Application to the asymmetric synthesis of 3-aryl dihydroisoquinolones and tetrahydroisoquinolines." In The 19th International Electronic Conference on Synthetic Organic Chemistry. MDPI, 2015. http://dx.doi.org/10.3390/ecsoc-19-a031.

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