Relevant bibliographies by topics / Cyclohexenones

Academic literature on the topic 'Cyclohexenones'

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Published: 4 June 2021
Last updated: 4 March 2023

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Journal articles on the topic "Cyclohexenones"

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Okoth, Dorothy A., and Neil A. Koorbanally. "Cardanols, Long Chain Cyclohexenones and Cyclohexenols from Lannea schimperi (Anacardiaceae)." Natural Product Communications 10, no. 1 (January 2015): 1934578X1501000. http://dx.doi.org/10.1177/1934578x1501000126.

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Alkenyl cyclohexenones (1a-d), alkenyl cyclohexenols (2a-c and 3b-d) and cardanols (4a-d) were isolated from the stem bark and root of Lannea schimperi. The alkenyl cyclohexenones (1a and 1d) and cardanols (4a and 4d) have side chains which have not been reported previously, in combination with the core skeletal structures. In addition, compounds 2a-c and 3b-d are all new cyclohexenols. Also isolated were the triterpenes, taraxerone and taraxerol, and sitosterol. The suite of compounds isolated (cyclohexenones and cyclohexenols) make up a nice biosynthetic pathway to the cardanols. The 5-[alkenyl]-4,5-dihydroxycyclohex-2-enone mixture (1a-d) exhibited good in vitro cytotoxicity against the Chinese Hamster Ovarian mammalian cell-line. The compounds were identified mainly from GCMS and NMR spectroscopic techniques.
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Hylden, Anne T., Eric J. Uzelac, Zeljko Ostojic, Ting-Ting Wu, Keely L. Sacry, Krista L. Sacry, Lin Xi, and T. Nicholas Jones. "Cyclization of 5-hexynoic acid to 3-alkoxy-2-cyclohexenones." Beilstein Journal of Organic Chemistry 7 (September 23, 2011): 1323–26. http://dx.doi.org/10.3762/bjoc.7.155.

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The one-pot cyclization of 5-hexynoic acid to produce 3-alkoxy-2-cyclohexenones proceeds in good yields (58–90%). 3-Hexynoic acid was converted to its acyl chloride with the aid of oxalyl chloride and was cyclized to 3-chloro-2-cyclohexenone upon addition of indium(III) chloride. Subsequent addition of alcohol nucleophiles led to the desired 3-alkoxy-2-cyclohexenones.
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Davis, BR, MG Hinds, and SJ Johnson. "Diterpene Synthesis. III. Acid-Catalyzed Cyclization of Methoxyphenylethyltrimethyl-Cyclohexanols, Cyclohexenols and Cyclohexenones." Australian Journal of Chemistry 38, no. 12 (1985): 1815. http://dx.doi.org/10.1071/ch9851815.

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Cyclization of the methoxyphenylethyltrimethylcyclohexanols (3), (4) and (5), the cyclohexenols (6) and (7) and the cyclohexenones (20) and (21), in the presence of a variety of acids, has been studied and the products analysed by chromatographic and spectroscopic techniques. Both cis - and trans-podocarpa-8,11,13-trienes are formed, along with the rearranged compounds (16), (17) and (30). These results parallel our earlier findings and contrast with some reports in the literature.
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Schuster, David I., Jie-Min Yang, Jan Woning, Timothy A. Rhodes, and Anton W. Jensen. "Mechanism of acid-catalyzed photoaddition of methanol to 3-alkyl2-cyclohexenones." Canadian Journal of Chemistry 73, no. 11 (November 1, 1995): 2004–10. http://dx.doi.org/10.1139/v95-247.

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Contrary to a previous report, it is concluded that formation of methanol adducts to 3-methyl-2-cyclohexenones and of deconjugated enones on irradiation of the enones in acidified solutions proceeds via protonation of the intermediate enone π,π* triplet excited state and not by protonation of a relatively long-lived ground state trans-cyclohexenone. A rate constant for protonation of the triplet state of 3-methyl-2-cyclohexenone by sulfuric acid of 1.7 × 109 M−1 s−1 was determined by laser flash photolysis in ethyl acetate. Based on quantum efficiencies of product formation, a rate constant of ca. 108 M−1 s−1 was estimated for protonation of the enone triplet by acetic acid, which is too small to cause measurable reduction in the triplet state lifetime in the mM concentration range used in the preparative studies. The intermediate carbocation can be trapped by methanol, or revert to starting enone or the exocyclic deconjugated enone by loss of a proton. Since products revert to starting materials in an acid-catalyzed process, there is an acid concentration at which the yields of products are optimal. This concentration is ca. 6 mM for acetic acid, but is only 0.1 mM for p-toluenesulfonic or sulfuric acids. Product formation could be quenched using 1-methylnaphthalene and cyclopentene as triplet quenchers; in the latter case, formation of [2 + 2] photoadducts was observed to compete with formation of methanol adducts. Quenching rate constants were determined by laser flash studies. Keywords: laser flash photolysis, kinetic absorption spectroscopy (KAS), photoacoustic calorimetry (PAC), protonation of triplet states, trans-cyclohexenones.
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Weir, D., J. C. Scaiano, and D. I. Schuster. "A reinvestigation of the interaction between triplet states of cyclohexenones and amines." Canadian Journal of Chemistry 66, no. 10 (October 1, 1988): 2595–600. http://dx.doi.org/10.1139/v88-407.

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Laser flash photolysis studies lead to the conclusion that the short-lived triplet states of cyclohexenones are readily quenched by amines. For example, in the case of 2-cyclohexen-1-one (1) its triplet state (τT = 40 ns in acetonitrile) is quenched by triethylamine with a rate constant of (9.0 ± 0.8) × 107 M−1 s−1. Cyclohexenone triplets are also quenched efficiently by DABCO and by triphenylamine leading to the formation of the corresponding amine radical cations. The new evidence reported rules out the involvement of long-lived detectable exciplexes.
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Helmchen, G., G. Franck, and K. Brödner. "Enantioselective Synthesis of Cyclohexenones." Synfacts 2010, no. 10 (September 22, 2010): 1166. http://dx.doi.org/10.1055/s-0030-1258649.

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VERHE, R. "ChemInform Abstract: 3-Isobutoxy-2-cyclohexenone: A Versatile Synthon for the Regiospecific Alkylation of Cyclohexenones." ChemInform 24, no. 52 (August 19, 2010): no. http://dx.doi.org/10.1002/chin.199352309.

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Das, Manik, and Kuntal Manna. "Bioactive Cyclohexenones: A Mini Review." Current Bioactive Compounds 11, no. 4 (December 30, 2015): 239–48. http://dx.doi.org/10.2174/157340721104151230104138.

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Holmes, Andrew B., and Nigel C. Madge. "Synthesis of 4,4-disubstituted cyclohexenones." Tetrahedron 45, no. 3 (January 1989): 789–802. http://dx.doi.org/10.1016/0040-4020(89)80110-3.

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Clot-Almenara, Lidia, Carles Rodríguez-Escrich, and Miquel A. Pericàs. "Desymmetrisation of meso-diones promoted by a highly recyclable polymer-supported chiral phosphoric acid catalyst." RSC Advances 8, no. 13 (2018): 6910–14. http://dx.doi.org/10.1039/c7ra13471a.

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Dissertations / Theses on the topic "Cyclohexenones"

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Clark, R. S. J. "The synthesis of cyclohexenones by rearrangement of bicyclo(2,2,2)octanones." Thesis, University of Cambridge, 1985. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.356675.

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Sheth, Ritesh B. "Development of new synthetic methodologies and the synthesis of natural products." Access to citation, abstract and download form provided by ProQuest Information and Learning Company; downloadable PDF file, 101 p, 2010. http://proquest.umi.com/pqdweb?did=1993336351&sid=2&Fmt=2&clientId=8331&RQT=309&VName=PQD.

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Williams, Katharine. "Investigation of a synthetic approach to polyfunctionalised cyclohexenones related to the antheminone and carvotacetone natural products." Thesis, University of Manchester, 2012. https://www.research.manchester.ac.uk/portal/en/theses/investigation-of-a-synthetic-approach-to-polyfunctionalised-cyclohexenones-related-to-the-antheminone-and-carvotacetone-natural-products(bab498dd-4ab6-4f07-81f1-72b29cbb2f60).html.

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The natural product 2 crotonyloxymethyl-(4R,5R,6R)-4,5,6-trihydroxy-cyclohex-2-enone (COTC) was isolated from the microorganism Streptomyces griseosporeus in 1975. It was shown to exhibit 'cytotoxic and cancerostatic activity'. The simplified synthetic analogue 2-crotonyl-oxymethyl-cyclohex-2-enone (COMC) has been shown to exhibit potent anti tumour activity against murine and human tumours in cell culture. For several years, the Whitehead research group at the University of Manchester have focused on the synthesis of COTC and COMC analogues in an attempt to produce compounds with enhanced cytotoxicity. In this thesis, the syntheses of several polyfunctionalised cyclohexenones are described. These compounds are analogues of COTC and COMC which also bear structural resemblance to the antheminone and carvotacetone natural products. Initially, the syntheses of six novel compounds from the chiral pool starting material (-)-quinic acid are described. The first four synthetic steps of each sequence were carried out by slight modification of procedures previously reported by the Whitehead research group. As part of the synthetic strategy, the diastereoselective conjugate addition of carbon nucleophiles to several polyfunctionalised cyclohexenones was investigated. The cytotoxicity of four of the synthetic analogues towards A549 non small cell lung cancer cells was investigated by use of an MTT assay. Two of the analogues were found to be more cytotoxic then COMC. The most effective synthetic analogue had an IC50 value of 2.2 μM. This analogue was more cytotoxic than similar molecules that had previously been synthesised by members of the Whitehead research group. Based on the results of the MTT assay, another two analogues were designed and their synthesis from (-)-quinic acid is described. The cytotoxicity of these analogues has yet to be assessed. In summary, the general synthetic strategies developed in this thesis will provide easy access to new analogues of the natural products, enabling the development of new cytotoxic compounds.
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Paramahamsan, Harinandini. "η6-Arenechromium Tricarbonyl Complexes: Conformational Analysis, Stereocontrol in Nucleophilic Addition and Applications in Organic Synthesis." Case Western Reserve University School of Graduate Studies / OhioLINK, 2005. http://rave.ohiolink.edu/etdc/view?acc_num=case1106262785.

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Kasprzyk, Milena, and milena kasprzyk@freehills com. "Synthetic Studies Towards the Tridachione Family of Marine Natural Products." Flinders University. Chemistry, Physics and Earth Sciences, 2008. http://catalogue.flinders.edu.au./local/adt/public/adt-SFU20081107.085933.

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Since the middle of the 20th century, significant interest has evolved from the scientific community towards the polypropionate family of marine natural products. A number of these compounds have been shown to possess significant biological activity, and this property, as well as their structural complexity, has driven numerous efforts towards their synthesis. The first chapter provides an introduction into the world of polypropionates, with a discussion on synthetic studies into a number of members of the tridachiapyrone family. Fundamental synthetic concepts utilised in this thesis towards the preparation of polyketides are also described, with a focus on their application towards the synthesis of 9,10-deoxytridachione, anti tridachiahydropyrone and syn tridachiahydropyrone. Chapter 2 describes the work undertaken towards the total synthesis of 9,10-deoxytridachione. The novel tandem conjugate addition-Dieckmann condensation of complex enones developed previously in the Perkins group was used to generate anti methylated cyclohexenones as key synthetic intermediates. The conversion of the cyclohexenones into the corresponding cyclohexadienes via allylic alcohols was attempted, utilising a Grignard-mediated reaction to achieve the selective 1,2-reduction. Studies into the Grignard-mediated reduction were also undertaken on seven additional cyclohexenones, in order to investigate the utility and scope of the reaction. The extension of the methodology previously developed for the synthesis of cyclohexenones is the subject of Chapter 3. This section describes investigations into the synthesis of stereochemically-diverse cyclohexenones from complex enones. The conjugate addition-Dieckmann condensation strategy was extended successfully towards the synthesis of a syn methylated cyclohexenone, which allowed the synthesis of the proposed true structure of tridachiahydropyrone to be pursued. The methodology developed in Chapter 3 was utilised in Chapter 4 to synthesise a model system of syn tridachiahydropyrone. A comparative analysis of the NMR data of the syn model, an anti model and anti tridachiahydropyrone with the natural product indicated that the true structure of tridachiahydropyrone may indeed have syn stereochemistry. The synthesis of syn tridachiahydropyrone was attempted, and to this end a suitable cyclohexanone was successfully synthesised. However, the subsequent methylation-elimination cascade failed to furnish the desired syn methylated cyclohexenone, producing only an anti methylated cyclohexanone. The stereochemistry of the methylation was deduced using high and low variable temperature NMR coupled with selective irradiation NOESY.
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Ohnemüller, Ulrike. "Effiziente Synthese hochsubstituierter enantiomerenreiner Cyclohexenone und Tetrahydroxanthenone." Berlin Logos-Verl, 2005. http://deposit.ddb.de/cgi-bin/dokserv?id=2793052&prov=M&dok_var=1&dok_ext=htm.

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Ohnemüller, Ulrike Kerstin. "Effiziente Synthese hochsubstituierter enantiomerenreiner Cyclohexenone und Tetrahydroxanthenone /." Berlin : Logos Verl, 2006. http://deposit.ddb.de/cgi-bin/dokserv?id=2793052&prov=M&dok_var=1&dok_ext=htm.

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Jaunet, Alex. "Synthetic approaches to naturally occuring cyclohexenone epoxides." Thesis, University of Sheffield, 2009. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.505527.

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Chen, Jianxin. "A study of the photorearrangements of crystalline dibenzobarrelene and cyclohexenone derivatives." Thesis, University of British Columbia, 1991. http://hdl.handle.net/2429/30985.

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Two series of compounds, 4,4-diarylcyclohexenones and 9-substituted dibenzobarrelenes, were synthesized and their photochemistry was investigated in the crystalline state and in solution medium. The differences in photoreactivity and product selectivity of these compounds between the solution and solid states have been determined, and possible structure-reactivity correlations are discussed based on X-ray crystallographic data for some of the substances. The photorearrangement of 4,4-diarylcyclohexenones was found to be affected moderately by the crystal lattice. The migratory aptitude of the aryl groups for 4-phenyl-4-arylcyclohexenones was shown to be controlled to a lesser extent by the electronic effect in the solid state compared to solution. Irradiation of 4,4-diphenyl-6-methyl-cyclohexenone in the crystalline phase gave the same photoproducts and a similar product distribution as that in the solution phase. In this case, conformational analysis reveals that both pseudo-axial and pseudo-equatorial phenyl groups of the enone moiety are capable of migrating. The di-π-methane rearrangement of a number of 9-substituted dibenzobarrelene derivatives gave two regioisomeric dibenzo-semibullvalene products upon photolysis in solution and in the solid state. In general, the effect of the crystalline environment on the reaction regioselectivity is found to be small. Resolved chiral substituents (handles) at the 9-position of the dibenzobarrelene moiety were used to force the compounds to crystallize in chiral space groups. Asymmetric inductions via photolysis of the chiral crystals varied from small to moderate depending on the nature of the chiral substituent. It was found that, in some cases, asymmetric induction in the solid state is significantly higher than in solution, but is lower in one instance. In addition, the chiral crystalline environment has different effects on the asymmetric inductions in a dual pathway di-π-methane rearrangement. The di-π-methane photorearrangement of 9,12-bridged dibenzobarrelene lactones was found to proceed very efficiently in solution and in the solid state. The unusual regioselectivity observed was rationalized in terms of an intramolecular steric effect rather than an electronic stabilizing effect. An absolute asymmetric synthesis with high optical yield was achieved by photolyses of chiral crystals of the achiral compound, methyl 3,5-dihydro-3-oxo-1H-5,9b[1',2']benzeno-naphtho[1′,2′-c]furan-4-carboxylate. Photochemical [2+2] cycloaddition of this substrate to 1,3-dienes was found to be mechanistically interesting, involving an excited triplet state of 1,3-diene which is formed by energy transfer. An unusual excited singlet state rearrangement of 9-chloromethyl substituted dibenzobarrelene diester was discovered. X-ray crystallographic analyses revealed that an intermolecular chlorine atom transfer is involved in the formation of unusual dibenzopentalene photoproducts. Finally, a novel solid state photochromism was found, and a radical species was proposed as the intermediate responsible for the observed photochromic phenomenon.
Science, Faculty of
Chemistry, Department of
Graduate
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Moralee, Andrew Charles. "The synthesis of geminally difluorinated cyclohexenols via Diels-Alder chemistry." Thesis, University of Birmingham, 2001. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.391382.

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Books on the topic "Cyclohexenones"

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Moralee, Andrew Charles. The synthesis of geminally difluorinated cyclohexenols via Diels-Alder chemistry. Birmingham: University of Birmingham, 2001.

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Wang, Bingbing. Photochemistry of 6-alkenyl-2-cyclohexenones: Synthetic studies towards precursors of ryanodol. 1998.

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Wang, Bingbing. Photochemistry of 6-alkenyl-2-cyclohexenones: Synthetic studies towards precursors of ryanodol. 1998.

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Ma, Shihong. Ring opening reactions of oxabicyclic compounds: Formation of substituted cyclohexadienes, cyclohexenols and cycloheptenols. 1996.

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Book chapters on the topic "Cyclohexenones"

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Toromanoff, Edmond. "Steric Course of the Kinetic 1,2 Addition of Anions to Conjugated Cyclohexenones." In Topics in Stereochemistry, 157–98. Hoboken, NJ, USA: John Wiley & Sons, Inc., 2007. http://dx.doi.org/10.1002/9780470147115.ch3.

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Prager, R. H., and C. M. Williams. "Reaction of Isatoic Anhydrides and Cyclohexenones." In Six-Membered Hetarenes with One Nitrogen or Phosphorus Atom, 1. Georg Thieme Verlag KG, 2005. http://dx.doi.org/10.1055/sos-sd-015-01722.

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Witulski, B., and C. Alayrac. "[2+2] Cycloadditions with Cyclopentenones and Cyclohexenones." In Three Carbon-Heteroatom Bonds: Ketenes and Derivatives, 1. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-024-01030.

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George, D. M., and R. L. Danheiser. "Formation of Cyclohexenones and Phenols by [4+2] Cycloadditions." In Three Carbon-Heteroatom Bonds: Thio-, Seleno-, and Tellurocarboxylic Acids and Derivatives; Imidic Acids and Derivatives; Ortho Acid Derivatives, 1. Georg Thieme Verlag KG, 2006. http://dx.doi.org/10.1055/sos-sd-023-00072.

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Taber, Douglass F. "The Williams Synthesis of (–)-Khayasin." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0101.

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The tetranortriterpenoid (–)-khayasin 3 recently emerged as a potent and selective insecticide against the Coconut leaf beetle Brontispa longissima. In considering a synthetic route to 3, Craig M. Williams of the University of Queensland envisioned (J. Org. Chem. 2012, 77, 8913) the convergent preparation of the allyl vinyl ether 1 and subsequent Claisen rearrangement to the enone 2. To pursue this strategy, the ketone 8 and the allylic alcohol 15 had to be prepared in enantiomerically pure form. To this end, the DIP-Cl-derived enolate of the ketone 7 was added to the aldehyde 6 to give a secondary alcohol, exposure of which to KH led to the enone 8 in high ee. Methyl triflate converted the enone into the enol ether 9. The α-pinene used in the preparation of DIP-Cl was 83% ee. The authors have optimized (Adv. Synth. Catal. 2009, 351, 1148) the Morita-Baylis-Hillman addition of cyclohexenone 10 to formaldehyde to give, after silylation, the enone 11. Methylation followed by DIP-mediated aldol condensation with 13 led to the alcohol 14. Exposure of the derived acetate to lithium diisopropylamide induced cyclization and dehydration. Deprotection completed the preparation (Tetrahedron 2006, 62, 7355) of 15. Fortunately, the enantiomers of 15 could be separated chromatographically. Material having >99% ee was taken onto the next step. Warming of 9 and 15 in the presence of acid delivered the coupled ketone 2 accompanied by the ether 1. Further heating of 1 converted it (Chem. Commun. 2011, 47, 2258) to 2. To form the last ring, the enone 2 was epoxidized to give 16. The reduction of 16 with aluminum amalgam gave preparatively useful amounts of 17. Esterification completed the synthesis of 3. Most total syntheses yield only the target natural product. In this biomimetic project, intermediates 15, 2, and 17 were themselves natural products, and oxidation of 17 delivered an additional natural product, 18. The preparation of 14 and of 8 underscores the importance of the asymmetric transformation of prochiral starting materials, cyclic and acyclic. Although DIP-Cl is used in stoichiometric amounts in both cases, it is not expensive. The preparation of 8, in particular, offers a potentially general approach to high ee-substituted cyclohexenones.
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Taber, Douglass. "The Toste Synthesis of ( + )-Fawcettimine." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0091.

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The tetracyclic Lycopodium alkaloid fawcettimine 3 and its derivatives are of interest as inhibitors of acetylcholine esterase. F. Dean Toste of the University of California, Berkeley recently reported (Angew. Chem. Int. Ed. 2007, 46, 7671) the first enantioselective synthesis of 3. The key to the synthesis was the rapid assembly of the enantiomerically-enriched hydrindane 2. The preparation of 2 began with the enantioselective Robinson annulation of the β-keto ester 4 with crotonaldehyde 5, mediated by the organocatalyst 6. In this protocol, originally developed by Karl Anker Jørgensen, the single stereogenic center was established by conjugate addition, presumably to the chiral iminium salt generated by the condensation of 5 with 6. Subsequent aldol (or more likely Mannich) cyclization followed by elimination gave 7. Hydrolysis and decarboxylation by heating with p-TsOH converted 7 to 1. This procedure was robust enough to allow preparation of a ten gram batch of 1. This Jørgensen annulation is the current method of choice for the enantioselective preparation of 2,5-dialkyl cyclohexenones. Conjugate addition of the propargyl anion equivalent 8 to 1 proceeded with the expected > 95:5 axial diastereoselectivity, to give the silyl enol ether 9. Exposure of the derived iodide 10 to catalytic [Ph3 PAu]Cl and AgBF4 induced smooth cyclization to the cis hydrindane 2. Before constructing the nine-membered ring amine of fawcettimine 3, it was first necessary to protect the ketone as the ketal. Pd-mediated coupling of the alkenyl iodide with the organoborane derived from 11 then proceeded smoothly, as did the subsequent hydroboration of the terminal alkene. Neither the mesylate nor the tosylate derived from 12 could be induced to cyclize. In contrast, intramolecular displacement of the iodide proceeded well, to give 13. Hydroboration followed by oxidation then gave 15, which on deprotection cyclized to (+)-fawcettimine 3. Several aspects of this synthesis are attractive. While the stereochemical outcome of the hydroboration of 14 could not necessarily be predicted with confidence, in fact it did not matter, as the stereogenic center adjacent to the ketone could be epimerized under the trifluoroacetic acid deprotection conditions, and only the desired diastereomer would be able to add in an intramolecular fashion to the cyclohexanone.
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Taber, Douglass. "Stereocontrolled Carbocyclic Construction: The Trauner Synthesis of the Shimalactones." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0080.

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Benjamin List of the Max Planck Institute, Mülheim devised (J. Am. Chem. Soc. 2008, 130, 6070) a chiral primary amine salt that catalyzed the enantioselective epoxidation of cyclohexenone 1 . Larger ring and alkyl-substituted enones are also epoxidized with high ee. Three- and four-membered rings are versatile intermediates for further transformation. Tsutomu Katsuki of Kyushu University developed (Angew. Chem. Int. Ed. 2008, 47, 2450) an elegant Al(salalen) catalyst for the enantioselective Simmons-Smith cyclopropanation of allylic alcohols such as 3. Kazuaki Ishihara of Nagoya University found (J. Am. Chem. Soc. 2007, 129, 8930) chiral amine salts that effected enantioselective 2+2 cycloaddition of α-acyloxyacroleins such as 5 to alkenes to give the cyclobutane 7 with high enantio- and diastereocontrol. Gideon Grogan of the University of York overexpressed (Adv. Synth. Cat. 2008, 349, 916) the enzyme 6-oxocamphor hydrolase in E. coli . The 6-OCH so prepared converted prochiral diketones such as 8 to the cyclopentane 9 in high ee. Richard P. Hsung of the University of Wisconsin found (Organic Lett. 2008, 10, 661) that the carbene produced by oxidation of the ynamide 10 cyclized to 11 with high de. Teck-Peng Loh of Nanyang Technological University extended (J. Am. Chem. Soc. 2008, 130, 7194) butane-2,3-diol directed cyclization to the preparation of the cyclopentane 15. Note that sidechain relative configuration is also controlled. We established (J. Org. Chem. 2008, 73, 3467) that the thermal ene reaction of 17 delivered the tetrasubstituted cyclopentane 18 as a single diastereomer. Tony K. M. Shing of the Chinese University of Hong Kong devised (J. Org. Chem. 2007, 72, 6610) a simple protocol for the conversion of carbohydrate-derived lactones such as 19 to the highly-substituted, enantiomerically-pure cyclohexenone 21. Hiromichi Fujioka and Yasuyuki Kita of Osaka University established (Organic Lett. 2007, 9, 5605) a chiral diol-mediated conversion of the cyclohexadiene 22 to the diastereomerically pure cyclohexenone 24. Dirk Trauner, now of the University of Munich, reported (Organic Lett. 2008, 10, 149) an elegant assembly of the neuritogenic polyketide shimalactone A 28.
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Ghomari, R., A. Bouferguene, P. E. Hoggan, and S. M. Mekelleche. "A Density Functional Theory Study of the Adsorption of 2-Cyclohexenone on Rh(111)." In Advances in Quantum Chemistry, 175–90. Elsevier, 2014. http://dx.doi.org/10.1016/b978-0-12-800536-1.00009-5.

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Taber, Douglass F. "Metal-Mediated C–C Ring Construction: The Lei Synthesis of (−)-Huperzine Q." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0076.

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Following the Szymoniak protocol, Morwenna S. M. Pearson-Long and Philippe Bertus of the Université du Maine added (Synthesis 2015, 47, 992) the Grignard rea­gent 2 to the nitrile 1 to give the cyclopropyl amine 3. Chen-Guo Feng of the Shanghai Institute of Organic Chemistry prepared (Chem. Commun. 2015, 51, 8773) the cyclobutane 6 by enantioselective conjugate addition of 5 to the unsaturated ester 4. Martin Kotora of Charles University showed (Eur. J. Org. Chem. 2015, 2868) that the zirconacycle from the eneyne 7 reacted with the aldehyde 8 to give, after iodina­tion, the alcohol 9. Xiaoming Feng of Sichuan University used (Angew. Chem. Int. Ed. 2015, 54, 1608) a scandium catalyst to effect the intramolecular Roskamp cyclization of 10 to 11. Celia Dominguez of CHDI observed (Org. Lett. 2015, 17, 1401) that the double alkylation of the ester 12 with the dibromide 13 proceeded with high diaste­reoselectivity, to give 14. Hirokazu Tsukamoto of Tohoku University cyclized (Chem. Commun. 2015, 51, 8027) 15 to 16 in high ee. Daniel J. Weix of the University of Rochester found (J. Am. Chem. Soc. 2015, 137, 3237) that under the influence of an enantiomerically-pure Ti catalyst, the organon­ickel species derived from 18 opened the prochiral epoxide 17 to give 19 in high ee. John F. Bower of the University of Bristol optimized (J. Am. Chem. Soc. 2015, 137, 463) conditions for the highly diastereoselective Rh-mediated cyclocarbonylation of 20 to 21. Margaret A. Brimble of the University of Auckland initiated (J. Org. Chem. 2015, 80, 2231) the construction of the cyclohexenone 24 by the diastereoselective addition of 23 to the unsaturated ester 22. Olivier Baslé and Marc Maduit of ENSC Rennes devised (Chem. Eur. J. 2015, 21, 993) conditions for the preparation of 26 by enantioselective conjugate addition to the cyclohexenone 25. Yoshito Kishi of Harvard University demonstrated (Tetrahedron Lett. 2015, 56, 3220) that the carbenoid generated from the epoxide 27 cyclized to 28 with high dia­stereoselectivity. Wenjun Tang, also of the Shanghai Institute of Organic Chemistry, developed (Angew. Chem. Int. Ed. 2015, 54, 3033) a Pd catalyst for the diastereoselec­tive (because it is enantioselective) cyclization of 29 to 30.
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10

Taber, Douglass. "Organocatalytic C-C Ring Construction: (+)-Ricciocarpin A (List) and (-)-Aromadendranediol (MacMillan)." In Organic Synthesis. Oxford University Press, 2011. http://dx.doi.org/10.1093/oso/9780199764549.003.0073.

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Yoshiji Takemoto of Kyoto University designed (Organic Lett. 2009, 11, 2425) an organocatalyst for the enantioselective conjugate addition of alkene boronic acids to γ-hydroxy enones, leading to 1 in high ee. Attempted Mitsunobu coupling led to the cyclopropane 2, while bromoetherification followed by intramolecular alkylation delivered the cyclopropane 3. Jeffrey W. Bode of the University of Pennsylvania demonstrated (Organic Lett. 2009, 11, 677) a remarkable dichotomy in the reactivity of N-heterocyclic carbenes. A triazolium precatalyst combined 4 and 5 to give 6, whereas an imidazolium precatalyst combined 4 and 5 to give 7. Xinmiao Liang of the Dalian Institute of Chemical Physics and Jinxing Ye of the East China University of Science and Technology devised (Organic Lett. 2009, 11, 753) a Cinchona -derived catalyst that converted the prochiral cyclohexenone 8 into the diester 10 in high ee. Rich G. Carter of Oregon State University found (J. Org. Chem. 2009, 74, 2246) a simple sulfonamide-based proline catalyst that effected the Mannich condensation of the prochiral ketone with ethyl glyoxalate 12 and the amine 13, leading to the amine 14. In the first pot of a concise, three-pot synthesis of (-)-oseltamivir, Yujiro Hayashi of the Tokyo University of Science combined (Angew. Chem. Int. Ed. 2009, 48, 1304) 15 and 16 in the presence of a catalytic amount of diphenyl prolinol TMS ether to give an intermediate nitro aldehyde. Addition of the phosphonate 17 led to a cyclohexenecarboxylate, that on the addition of the thiophenol 18 equilibrated to the ester 19. Ying-Chun Chen of Sichuan University used (Organic Lett. 2009, 11, 2848) a related diaryl prolinol TMS ether to direct the condensation of the readily-prepared phosphorane 20 with the unsaturated aldehyde 21 to give the cyclohexenone 22. Armando Córdova of Stockholm University also used (Tetrahedron Lett. 2009, 50, 3458) diphenyl prolinol TMS ether to mediate the addition of 24 to 23. The subsequent intramolecular aldol condensation proceeded with high diastereocontrol, leading to 25. Benjamin List of the Max-Planck Institut, Mülheim employed (Nat. Chem. 2009, 1, 225) a MacMillan catalyst for the reductive cyclization of 26.
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Conference papers on the topic "Cyclohexenones"

1

Wisetsai, A., R. Lekphrom, and FT Schevenels. "Roxydienone, a novel cyclohexenone from Trachyspermum roxburghianum." In 67th International Congress and Annual Meeting of the Society for Medicinal Plant and Natural Product Research (GA) in cooperation with the French Society of Pharmacognosy AFERP. © Georg Thieme Verlag KG, 2019. http://dx.doi.org/10.1055/s-0039-3400153.

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