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Relevant bibliographies by topics / Carbocyclic ring synthesis

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Academic literature on the topic 'Carbocyclic ring synthesis'

Author: Grafiati

Published: 4 June 2021

Last updated: 16 February 2022

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Journal articles on the topic "Carbocyclic ring synthesis"

1

KILBURN, J. D. "ChemInform Abstract: Saturated Carbocyclic Ring Synthesis." ChemInform 26, no. 3 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199503271.

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KILBURN, J. D. "ChemInform Abstract: Saturated Carbocyclic Ring Synthesis." ChemInform 25, no. 45 (August 18, 2010): no. http://dx.doi.org/10.1002/chin.199445282.

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KILBURN, J. D. "ChemInform Abstract: Saturated Carbocyclic Ring Synthesis." ChemInform 23, no. 32 (August 21, 2010): no. http://dx.doi.org/10.1002/chin.199232265.

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KILBURN, J. "ChemInform Abstract: Saturated Carbocyclic Ring Synthesis." ChemInform 24, no. 10 (August 20, 2010): no. http://dx.doi.org/10.1002/chin.199310303.

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LEE, T. V. "ChemInform Abstract: Saturated Carbocyclic Ring Synthesis." ChemInform 22, no. 25 (August 23, 2010): no. http://dx.doi.org/10.1002/chin.199125277.

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Liu, Peng, and Chung K. Chu. "Enantiomeric synthesis of carbocyclic analogs of D- and L-6-azapyrimidine ribonucleosides." Canadian Journal of Chemistry 84, no. 4 (April 1, 2006): 748–54. http://dx.doi.org/10.1139/v06-052.

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An effective and practical synthesis of carbocyclic D- and L-6-azapyrimidine nucleosides (38) was described. Starting from D-ribose, a new efficient methodology for the synthesis of L-2,3-O-cyclohexylidene-4-cyclopentenone (23) was developed via a ring-closing metathesis, which was applied for the synthesis of L-cyclopentyl-6-azapyrimidine nucleosides (68). The regiospecific introduction of 6-azauracil on the carbocyclic moiety (9 and 25) was also achieved by masking its N3 position with a 4-methylthio group.Key words: carbocyclic nucleosides, 6-azapyrimidine nucleosides, enantiomeric synthesis.

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Yuasa, Hideya, Monica M. Palcic, and Ole Hindsgaul. "Synthesis of the carbocyclic analog of uridine 5′-(α-D-galactopyranosyl diphosphate) (UDP-Gal) as an inhibitor of β(1 → 4)-galactosyltransferase." Canadian Journal of Chemistry 73, no. 12 (December 1, 1995): 2190–95. http://dx.doi.org/10.1139/v95-272.

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Uridine 5′-(5a-carba-α-D-galactopyranosyl diphosphate), the carbocyclic analog of UDP-galactose where the ring oxygen of the galactose residue is replaced by a methylene group, was chemically synthesized as a potential inhibitor of galactosyltransferases. It was found to be a competitive inhibitor of UDP-galactose: N-acetylglucosamine β(1 → 4)-galactosyltransferase from bovine milk (EC 2.4.1.22) with a Ki value of 58 µM, similar to the Km value for UDP-galactose (25 µM). Keywords: carbocycles, UDP-5a-carbagalactose, galactosyltransferase, glycosyltransferase inhibitor.

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Yamatoya, Y., M. Ishikura, and N. Katagiri. "Synthesis of carbocyclic nucleosides bearing a cyclopropane ring." Nucleic Acids Symposium Series 42, no. 1 (November 1, 1999): 23–24. http://dx.doi.org/10.1093/nass/42.1.23.

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Griffith, Daniel R., and Aaron H. Shoemaker. "Synthetic Approaches to Non-Tropane, Bridged, Azapolycyclic Ring Systems Containing Seven-Membered Carbocycles." Synthesis 53, no. 01 (September 11, 2020): 65–78. http://dx.doi.org/10.1055/s-0040-1707385.

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AbstractThis Short Review highlights various synthetic approaches to bridged azabicyclic ring systems containing seven-membered carbocyclic rings. Such ring systems are common to a number of biologically active natural products. The seven-membered ring in such systems is generally formed in one of four ways: 1) cyclization of an acyclic precursor; 2) ring expansion or rearrangement of a different ring size; 3) cycloaddition; and 4) use of a synthetic building block with the seven-membered ring already present. Representative examples of each approach from both total synthesis and methodological studies are discussed, with an emphasis on work publishedin the last twenty years.1 Introduction2 Cyclization Reactions3 Ring Expansions and Rearrangements4 Cycloadditions5 Strategies Involving Seven-Membered Ring Building Blocks6 Conclusion

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Gao, Yuan, Xiaonan Wang, Zhonglin Wei, Jungang Cao, Dapeng Liang, Yingjie Lin, and Haifeng Duan. "Asymmetric synthesis of spirooxindole–pyranoindole products via Friedel–Crafts alkylation/cyclization of the indole carbocyclic ring." New Journal of Chemistry 44, no. 23 (2020): 9788–92. http://dx.doi.org/10.1039/d0nj00074d.

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Dissertations / Theses on the topic "Carbocyclic ring synthesis"

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Singh, Rajinder. "Free radical ring expansion reactions." Thesis, University of Oxford, 1991. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.293427.

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White, Andrew Jonathan. "The development of novel photocycloaddition reactions for carbo- and heterocyclic synthesis." Thesis, University of East Anglia, 2000. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.323289.

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3

Hoffman, William Christopher. "Synthesis of fused carbocycles from benzoic acids via radical and anionic annulation procedures /." The Ohio State University, 1987. http://rave.ohiolink.edu/etdc/view?acc_num=osu1487331541711284.

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Claridge, Stephen. "Applications of cobalt stabilised carbonium ions to the synthesis of fused ring carbocycles." Thesis, Kingston University, 1996. http://eprints.kingston.ac.uk/20593/.

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This programme of work has been aimed at developing novel annulation reactions in order to furnish a variety of carbocyclic and heterocyclic ring systems: In all of the examples investigated the key cyclisation step was achieved using a Nicholas reaction, that is, the reaction of a dicobalt hexacarbonyl stabilised propargylic carbonium ion with an intramolecular nucleophile. After an initial review of both cyclisation reactions and the chemistry of organocobalt clusters, the results of these investigations are detailed. In the initial investigations a range of 1,2-disubstituted cycloalkanes were synthesised that contained a dicobalt hexacarbonyl complexed propargyl ether at the a-carbon atom and a pendant silyl enol ether at the ß-carbon atom. These molecules were successfully cyclised, using boron trifluoride diethyl etherate followed by decomplexation of the dicobalt cluster, to afford a bicyclo[4:3:0]nonane, two bicyclo[3:3:0]octanes and a bicyclo[5:3:0]decane. The relative stereochemistry at the fused ring junction for all these molecules was determined on the basis of their corresponding =c NMR spectra. An analogous reaction was successfully achieved between a dicobalt hexacarbonyl complexed prop argyl ether and a terminal alkene, using titanium (IV) chloride, to afford a cis fused bicyclo[3:3:0]octane into which a chlorine atom had been incorporated. A subsequent investigation led to the development of a novel benzopyran synthesis. In this approach two benzopyran derivatives were produced from the one key cyclisation precursor. It was observed that they not only contained different functionalities but that the relative stereochemistry at the newly formed carbon-carbon bonds was different. A benzopyran, that possessed the isopropenyl group, exhibited a trans stereochemistry, whereas the stereochemistry for a second fluorinated derivative appeared, from the magnitude of the coupling constant (6 Hz), to exhibit a cis stereochemistry. The concluding investigation focused upon the intramolecular cyclisation of a precursor derived from S-C - )-citronellal. Both a silyl enol ether derivative andan allyl silane derivative were successfully cyclised, using the Nicholas reaction, to affordtrisubstituted cycloalkanes in low but unoptimised yields. An additional investigation using a dicobalt hexacarbonyl complexed derivative possessing a pendant trisubstituted alkene underwent a novel cyclisation reaction to furnish, upon decomplexation, two trisubstituted cycloalkane derivatives. For one of the cycloalkanes produced, the relative stereochemistry of the ring substituents at the newly formed carbon-carbon bond was found to be trans.

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Walls, Steven B. "The synthesis of medium-ring carbocycles by tandem oxonium ylide generation and [2,3]-sigmatropic rearrangement." Thesis, University of Nottingham, 2005. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.416880.

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Dzwiniel, Trevor L. "Seven-membered carbocycle synthesis by cobalt-mediated [3 + 2 + 2] allyl/alkyne cycloaddition reactions and novel [5 + 2] cyclopentadiene/alkyne ring expansions." Thesis, National Library of Canada = Bibliothèque nationale du Canada, 1999. http://www.collectionscanada.ca/obj/s4/f2/dsk1/tape7/PQDD_0033/NQ46833.pdf.

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Frigell, Jens. "Synthesis of O-linked Carbasugar Analogues of Galactofuranosides and N-linked Neodisaccharides." Doctoral thesis, Stockholms universitet, Institutionen för organisk kemi, 2010. http://urn.kb.se/resolve?urn=urn:nbn:se:su:diva-43561.

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In this thesis, carbohydrate mimicry is investigated through the syntheses of carbohydrate analogues and evaluation of their inhibitory effects on carbohydrate-processing enzymes. Galactofuranosides are interesting structures because they are common motifs in pathogenic microorganisms but not found in mammals. M.tuberculosis, responsible for the disease tuberculosis, has a cell wall containing a repeating unit of alternating (1→5)- and (1→6)-linked β-D-galactofuranosyl residues. Synthetic inhibitors of the enzymes involved in the biosynthesis of the cell wall could find great therapeutic use. The first part of this thesis describes the first synthesis of the hydrolytically stable carbasugar analogue of galactofuranose, 4a-carba-β-D-Galf, and the synthetic work of synthesising β-linked pseudodisaccharides containing carba-Galf, which were tested for glycosyltransferease inhibitory activity. The pseudodisaccharide carba-Galf-(β1→5)-carba-Galf was found to be a moderate inhibitor of the glycosyltransferase GlfT2 of M.tuberculosis. The thesis also describes how a general method towards biologically relevant α-linked carba-Galf ethers was developed. The final part of this thesis is focussed on the formation of nitrogen-linked monosaccharides without the participation of the anomeric centre. Such a mode of coupling is called tail-to-tail neodisaccharide formation. The couplings of carbohydrate derivatives via the Mitsunobu reaction are successfully reported herein. The method describes the key introduction of an allylic alcohol in the electrophile and the subsequent functionalisation of the alkene to obtain the neodisaccharide. Two synthesised neodisaccharides presented in this thesis have been sent to be tested for glycosidase inhibitory activity.
At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 3: Manuscript. Paper 4: Manuscript. Paper 5: Manuscript. Paper 6: Manuscript.

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Song, Eunho Krafft Marie E. "Ring-closing metathesis for the synthesis of carbocyclic and heterocyclic intramolecular Baylis-Hillman adducts." Diss., 2005. http://etd.lib.fsu.edu/theses/available/etd-05062005-172529.

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Thesis (M.S.)--Florida State University, 2005.
Advisor: Dr. Marie E. Krafft, Florida State University, College of Arts and Sciences, Dept. of Chemistry and Biochemistry. Title and description from dissertation home page (viewed Sept. 19, 2005). Document formatted into pages; contains 147 pages. Includes bibliographical references.

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9

"Construction of carbocycles from carbohydrates via 1,3-dipolar cycloaddition." Thesis, 2011. http://library.cuhk.edu.hk/record=b6075206.

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A 5-membered INOC cycloadduct 84 was employed to prepare alcohol 91, which was transformed into several cyclopent-2-enone derivatives 94-96.
By using intramolecular nitrile oxide-alkene cycloaddition (INOC) as the kep step to construct hydroxylated carbocycles, gabosine F was synthesized for the first time from L-arabinose. Hence, theoretically, gabosine B, which is the enantiomer of gabosine F, can also be synthesized from D-arabinose by the same synthetic strategy.
In this thesis, the background information on the construction of carbocycles from carbohydrates via intramolecular 1,3-dipolar cycloaddition is presented. A review regarding the syntheses of gabosine B and cocaine are also descibed.
Starting with D-ribose, INAC of nitrones 113, 129, and 140, bearing an alpha/beta-unsaturated ester as the dipolarophile was studied. The INAC endo-cycloadduct 141 (cycloheptane) was converted into natural cocaine sucessfully, together with cocaine analogues 162,169,170,173,175, and 177.
The regioselectivity of intramolecular nitrone-alkene cycloaddition (INAC) was studied. The INAC of hept-6-enose nitrone 98, with a 3,4- trans-pentylidene acetal as the only blocking group, afforded endo-cycloadduct 97 (cycloheptane) exclusively. This result concluded that the regiospecific outcome of this INAC reaction is due to the present of the 3,4-trans-pentylidene acetal blocking group.
To investigate the regioselectivity in INAC of hex-5-enose with a 2,3- trans-pentylidene acetal blocking group, nitrones 178 and 195 were prepared from D-mannitol. endo-Cycloadducts (cyclohexanes) were afforded exclusively.
So, King Ho.
Adviser: Kung Ming Tony Shing.
Source: Dissertation Abstracts International, Volume: 73-06, Section: B, page: .
Thesis (Ph.D.)--Chinese University of Hong Kong, 2011.
Includes bibliographical references (leaves 165-171).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [201-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstract also in Chinese.

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10

"Synthetic studies of carbocycles from carbohydrates." Thesis, 2008. http://library.cuhk.edu.hk/record=b6074641.

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An enone was synthesized from delta-D-gluconolactone in four steps, involving a one-pot TPAP oxidation-K2CO3-mediated intramolecular Horner-Wadsworth-Emmons (HWE) olefination as the key step.
In this thesis, a review regarding intramolecular direct aldol reaction from 1971 to 2008 is presented. The background information on pseudo-acarviosin, valiolamine and its containing compounds, gabosines and human glutathione transferase (hGST) is introduced.
Intramolecular direct aldol reaction was investigated for the construction of cyclohexanones and cycloheptanones from carbohydrates. Amine bases, amide bases and L-proline were employed to facilitate cyclization of 1,5- and 1,6-diketones successfully. These 1,5- and 1,6-diketones were prepared from carbohydrates by standard transformations. Different bases were employed to promote cyclization of 1,5-diketone derived from D-glucose to give cyclohexanones stereoselectively.
Intramolecular nitrile oxide-alkene cycloaddition (INOC) was studied with sugar derivatives having free hydroxyl groups. The INOC reaction, by incorporating chloramine-T and silica gel for the formation of nitrile oxide from oxime, proceeded smoothly with one, two, and four unmasked hydroxyl groups to give cyclopentanes and cyclohexanes.
The polyhydroxylated carbocycles constructed from sugars were successfully transformed into a variety of target molecules including pseudo-acarviosin, valiolamine and its containing compounds and gabosines. A series of 2-crotonyloxymethyl-(4 R,5R,6R)-4,5,6-trihydroxy-2-cyclohexenone (COTC) analogues as inhibitors of hGST were prepared in order to study the structure-activity relationships.
Cheng, Hau Man.
Adviser: Tony K. M. Shing.
Source: Dissertation Abstracts International, Volume: 70-06, Section: B, page: 3508.
Thesis (Ph.D.)--Chinese University of Hong Kong, 2008.
Includes bibliographical references (leaves 214-224).
Electronic reproduction. Hong Kong : Chinese University of Hong Kong, [2012] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Electronic reproduction. [Ann Arbor, MI] : ProQuest Information and Learning, [200-] System requirements: Adobe Acrobat Reader. Available via World Wide Web.
Abstracts in English and Chinese.
School code: 1307.

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Books on the topic "Carbocyclic ring synthesis"

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Carbocycle construction in terpene synthesis. New York, N.Y: VCH, 1988.

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Book chapters on the topic "Carbocyclic ring synthesis"

1

Blanchard, Nicolas, and Jacques Eustache. "Synthesis of Natural Products Containing Medium-Size Carbocycles by Ring-Closing Alkene Metathesis." In Metathesis in Natural Product Synthesis, 1–43. Weinheim, Germany: Wiley-VCH Verlag GmbH & Co. KGaA, 2010. http://dx.doi.org/10.1002/9783527629626.ch1.

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Roy, M. N., V. N. G. Lindsay, and A. B. Charette. "Synthesis of Carbocyclic Bicyclo Ring Systems." In Stereoselective Synthesis 1 Stereoselective Reactions of Carbon—Carbon Double Bonds, 1. Georg Thieme Verlag KG, 2011. http://dx.doi.org/10.1055/sos-sd-201-00409.

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"A. Synthesis." In Carbocyclic Three- and Four Membered Ring Compounds, edited by Armin de Meijere. Stuttgart: Georg Thieme Verlag, 1997. http://dx.doi.org/10.1055/b-0035-112531.

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Taber, Douglass F. "Carbocyclic Ring Construction: The Nicolaou Synthesis of Myceliothermophin E." In Organic Synthesis. Oxford University Press, 2017. http://dx.doi.org/10.1093/oso/9780190646165.003.0082.

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Nan Zheng of the University of Arkansas developed (Adv. Synth. Catal. 2014, 356, 2831) a Ru catalyst for the addition of an amino cyclopropane 1 to an alkyne 2 to give 3. The reaction proceeded with high regiocontrol, but only modest stereocontrol. Alain De Mesmaeker of Syngenta Crop Protection, Switzerland found (Tetrahedron Lett. 2014, 55, 6577) that the β,γ-unsaturated amide 4 worked particularly well as a precursor to the keteniminium that cyclized to give, after hydrolysis, the cyclobutanone 5. Baeyer–Villiger oxidation of 5 led to 5-deoxystrigol 6. David Tymann and Martin Hiersemann of the Technische Universität Dortmund have been exploring (Org. Lett. 2014, 16, 4062; Synthesis 2014, 46, 3110) the intramolecular carbonyl ene reaction as a tool for the assembly of highly substituted cyclopentanes, as in the conversion of 7 to 8. On oxidation, 8 was readily carried on to the alkene 9. James L. Leighton of Columbia University conceived (J. Am. Chem. Soc. 2014, 136, 9878) the cascade transformation of 10 to 12. Deprotonation/silylation set the stage for Claisen rearrangement to give 11. The subsequent Cope rearrangement is an equilibrium process, driven by the ring strain of 11. K. C. Nicolaou of Rice University described (Angew. Chem. Int. Ed. 2014, 53, 10970) the total synthesis of the cytotoxic tetramic acid derivative myceliothermophin E 15. A key step in the synthesis was the intramolecular Michael addition/ aldol condensation that converted 13 to 14.

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Taber, Douglass F. "Organocatalysis of Carbocyclic Construction: The MacMillan Synthesis of (+)-Frondosin B." In Organic Synthesis. Oxford University Press, 2013. http://dx.doi.org/10.1093/oso/9780199965724.003.0071.

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One of the more powerful applications of organocatalysis has been the enantioselective transformation of preformed prochiral rings. In the five-membered ring series, Nobuyuki Mase of Shizuoka University effected (Synlett 2010, 2340) enantioselective addition of malonate to cyclopentenone 1, and Eric N. Jacobsen of Harvard University devised (Angew. Chem. Int. Ed. 2010, 49, 9753) a guanidinium catalyst for the Claisen rearrangement of 4 to 5. Jacek Mlynarski of Jagiellonian University accomplished (Tetrahedron Lett. 2010, 51, 4088) the enantioselective hydroxymethylation of 6. This worked equally well for cyclopentanone and cycloheptanone. The dynamic kinetic resolution/reductive amination of 8 described (Angew. Chem. Int. Ed. 2010, 49, 4612) by Benjamin List of the Max-Planck-Institut Mülheim worked best with cyclohexanones such as 8. Organocatalysts can also be effective for the construction of carbocyclic rings. Teck-Peng Loh of Nanyang Technological University found (Chem. Sci. 2010, 1, 739) a commercial phosphine catalyst that efficiently mediated the condensation of 10 with 11. David W. C. MacMillan of Princeton University used (J. Am. Chem. Soc. 2010, 132, 10015) a SOMO catalyst to combine 13 with 14 to make 15. Dawei Ma of the Shanghai Institute of Organic Chemistry employed (Org. Lett. 2010, 12, 3634) the Hayashi catalyst in the double Michael condensation of 16 with 17. Daniel Romo of Texas A&M University showed (Org. Lett. 2010, 12, 3764) that the appropriate organocatalyst could direct 19 to either diastereomer of the β-lactone 20. Professor Romo also reported (Angew. Chem. Int. Ed. 2010, 49, 9479) the desymmetrization of 2-alkyl cyclohexane-1,3-diones using a similar approach. In the six-membered ring series, José Alemán and José Luis García Ruano of the Universidad Autónoma de Madrid carried out (Eur. J. Org. Chem. 2010, 4482) Robinson annulation of 17 with 21. Ying-Chun Chen of Sichuan University, again using the Hayashi catalyst, reported (Angew. Chem. Int. Ed. 2010, 49, 6418) the addition of 17 to 23 to give 24. In another elegant application of visible light–mediated organocatalysis, Professor MacMillan described (Chem. Sci. 2010, 1, 37) the addition of the commercial boronic acid 25 to 17.

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Taber, Douglass F. "The Tan/Chen/Yang Synthesis of Schindilactone A." In Organic Synthesis. Oxford University Press, 2015. http://dx.doi.org/10.1093/oso/9780190200794.003.0088.

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Schindilactone A 3 is one of a closely related family of polycyclic lactones that have been used in China for the treatment of rheumatic disease. The synthesis of 3 reported (Angew. Chem. Int. Ed. 2011, 50, 7373) by Ye-Feng Tang of Tsinghua University and Jia-Hua Chen and Zhen Yang of Peking University is an elegant tour of metal-mediated bond construction, as exemplified by the cyclization of 1 to 2. The preparation of 1 began with the Diels-Alder reaction of 4 with the butadiene 5. Addition of methyl magnesium chloride converted 6 to the crystalline lactone 7. Angular hydroxylation followed by ring expansion gave the bromo enone 8, which was homologated to the lactone 11. Apparently, the bulky silyloxy group directed the addition of the butenyl Grignard reagent 10 to the top face of the ketone carbonyl. Hydroxylation of the lactone followed by the addition of 12 then gave 1 as a mixture of diastereomers. Only one of the two diastereomers of 1 could undergo ring-closing metathesis to form the second of the three carbocyclic rings of 3. The two lactol diastereomers were in equilibrium with each other by way of the open-chain enone. When MgBr2 was added to encourage equilibration, the metathesis proceeded to completion to give 2. The tertiary alcohol of 2 was esterified with 2-butynoic acid to give 13. Intramolecular Pauson-Khand cyclization, using the optimized protocol developed by the authors, then delivered the enone 13, completing the last carbocyclic ring of 3. The last remarkable metal-mediated reaction in the synthesis was the oxidative carbonylation of 14 to 15. It is not clear if the postcarbonylation event is direct Pd-mediated C–O bond formation or the intramolecular addition of alkoxide to a transient butenolide. To complete the synthesis, 15 was methylated, then deprotonated and kinetically quenched to set the proper relative configuration of the last methyl group. Remarkably, despite the presence in the molecule of three other acidic protons, including the one that had just been removed and kinetically reset, exposure of the acetate 16 to a large excess of base, followed by oxidation, gave clean conversion to schindilactone A 3.

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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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"A. Synthesis : 3. By Ring Enlargement (I)." In Carbocyclic Three- and Four-Membered Ring Compounds, edited by Armin de Meijere. Stuttgart: Georg Thieme Verlag, 1997. http://dx.doi.org/10.1055/b-0035-110783.

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"A. Synthesis : 3. By Ring Enlargement (II)." In Carbocyclic Three- and Four-Membered Ring Compounds, edited by Armin de Meijere. Stuttgart: Georg Thieme Verlag, 1997. http://dx.doi.org/10.1055/b-0035-110784.

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"A. Synthesis : 3. By Ring Enlargement (III)." In Carbocyclic Three- and Four-Membered Ring Compounds, edited by Armin de Meijere. Stuttgart: Georg Thieme Verlag, 1997. http://dx.doi.org/10.1055/b-0035-110785.

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