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Großkopf J, Kratz T, Rigotti T, Bach T. Enantioselective Photochemical Reactions Enabled by Triplet Energy Transfer. Chem Rev 2021; 122:1626-1653. [PMID: 34227803 DOI: 10.1021/acs.chemrev.1c00272] [Citation(s) in RCA: 160] [Impact Index Per Article: 53.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022]
Abstract
For molecules with a singlet ground state, the population of triplet states is mainly possible (a) by direct excitation and subsequent intersystem crossing or (b) by energy transfer from an appropriate sensitizer. The latter scenario enables a catalytic photochemical reaction in which the sensitizer adopts the role of a catalyst undergoing several cycles of photon absorption and subsequent energy transfer to the substrate. If the product molecule of a triplet-sensitized process is chiral, this process can proceed enantioselectively upon judicious choice of a chiral triplet sensitizer. An enantioselective reaction can also occur in a dual catalytic approach in which, apart from an achiral sensitizer, a second chiral catalyst activates the substrate toward sensitization. Although the idea of enantioselective photochemical reactions via triplet intermediates has been pursued for more than 50 years, notable selectivities exceeding 90% enantiomeric excess (ee) have only been realized in the past decade. This review attempts to provide a comprehensive survey on the various photochemical reactions which were rendered enantioselective by triplet sensitization.
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Affiliation(s)
- Johannes Großkopf
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thilo Kratz
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thomas Rigotti
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, D-85747 Garching, Germany
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Kinoshita T, Imai Y, Fukuhara G. Hydrostatic Pressure-Controllable Chiroptical Properties of Chiral Perylene Bisimide Dyes: A Chiral Aggregation Case. J Phys Chem B 2021; 125:5952-5958. [PMID: 34032446 DOI: 10.1021/acs.jpcb.1c02112] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
Abstract
Hydrostatically pressurized spectroscopic and lifetime decay analyses of optically active perylene bisimides were demonstrated in the pressure range of 0.1-320 MPa to show a π-stacked aggregation. The hydrostatic pressure-induced excitation and circular dichroism spectral changes of the fluorescence perylene dye enabled us to differentiate the slight pressure-sensitive aggregates. This work will lead to a new strategy for creating a pressure-responsive supramolecular polymerization material.
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Affiliation(s)
- Tomokazu Kinoshita
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan
| | - Yoshitane Imai
- Department of Applied Chemistry, Faculty of Science and Engineering, Kindai University, 3-4-1 Kowakae, Higashi-Osaka, Osaka 577-8502, Japan
| | - Gaku Fukuhara
- Department of Chemistry, Tokyo Institute of Technology, 2-12-1 Ookayama, Meguro-ku, Tokyo 152-8551, Japan.,JST, PRESTO, 4-1-8 Honcho, Kawaguchi, Saitama 332-0012, Japan
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Li X, Kutta RJ, Jandl C, Bauer A, Nuernberger P, Bach T. Photochemically Induced Ring Opening of Spirocyclopropyl Oxindoles: Evidence for a Triplet 1,3‐Diradical Intermediate and Deracemization by a Chiral Sensitizer. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.202008384] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Affiliation(s)
- Xinyao Li
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Roger J. Kutta
- Institut für Physikalische und Theoretische Chemie Universität Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Christian Jandl
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Andreas Bauer
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie Universität Regensburg Universitätsstr. 31 93053 Regensburg Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC) Technische Universität München Lichtenbergstraße 4 85747 Garching Germany
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Li X, Kutta RJ, Jandl C, Bauer A, Nuernberger P, Bach T. Photochemically Induced Ring Opening of Spirocyclopropyl Oxindoles: Evidence for a Triplet 1,3-Diradical Intermediate and Deracemization by a Chiral Sensitizer. Angew Chem Int Ed Engl 2020; 59:21640-21647. [PMID: 32757341 PMCID: PMC7756555 DOI: 10.1002/anie.202008384] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2020] [Revised: 07/23/2020] [Indexed: 12/17/2022]
Abstract
The photochemical deracemization of spiro[cyclopropane‐1,3′‐indolin]‐2′‐ones (spirocyclopropyl oxindoles) was studied. The corresponding 2,2‐dichloro compound is configurationally labile upon direct irradiation at λ=350 nm and upon irradiation at λ=405 nm in the presence of achiral thioxanthen‐9‐one as the sensitizer. The triplet 1,3‐diradical intermediate generated in the latter reaction was detected by transient absorption spectroscopy and its lifetime determined (τ=22 μs). Using a chiral thioxanthone or xanthone, with a lactam hydrogen bonding site as a photosensitizer, allowed the deracemization of differently substituted chiral spirocyclopropyl oxindoles with yields of 65–98 % and in 50–85 % ee (17 examples). Three mechanistic contributions were identified to co‐act favorably for high enantioselectivity: the difference in binding constants to the chiral thioxanthone, the smaller molecular distance in the complex of the minor enantiomer, and the lifetime of the intermediate 1,3‐diradical.
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Affiliation(s)
- Xinyao Li
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Roger J Kutta
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Christian Jandl
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Andreas Bauer
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
| | - Patrick Nuernberger
- Institut für Physikalische und Theoretische Chemie, Universität Regensburg, Universitätsstr. 31, 93053, Regensburg, Germany
| | - Thorsten Bach
- Department Chemie and Catalysis Research Center (CRC), Technische Universität München, Lichtenbergstraße 4, 85747, Garching, Germany
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Achiral Zeolites as Reaction Media for Chiral Photochemistry. Molecules 2019; 24:molecules24193570. [PMID: 31581744 PMCID: PMC6804131 DOI: 10.3390/molecules24193570] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/18/2019] [Revised: 09/27/2019] [Accepted: 09/30/2019] [Indexed: 11/17/2022] Open
Abstract
Obtaining enantiomerically-enriched photoproducts from achiral reactants has been a long-sought goal. The various methods developed to achieve chiral induction in photoproducts during the last fifty years still suffer from a lack of predictability, generality, and simplicity. With the current emphasis on green chemistry, obtaining enantiomerically enriched products via photochemistry is a likely viable alternative for the future. Of the various approaches developed during the last three decades, the one pioneered in the author's laboratory involved the use of commercially-available and inexpensive achiral zeolites as the media. This approach does not use any solvent for the reaction. Examples from these studies are highlighted in this article. Since no chiral zeolites were available, when the work was initiated in the author's laboratory, commercially-available zeolites X and Y were modified with chiral inductors so that the reaction space becomes chiral. The results obtained established the value of chirally-modified, commercial zeolites as media for achieving chiral induction in photochemical reactions. A recent report of the synthesis of a chiral zeolite is likely to stimulate zeolite-based chiral photochemistry in synthesizing enantiomerically-pure organic molecules. The availability of chiral zeolites in future is likely to energize research in this area. Our earlier observations on this topic, we believe, would be valuable for progress of the field. Keeping this in mind, I have summarized the work carried out in our laboratory on chiral photochemistry on chirally-modified zeolites. This review does not include examples where high chiral induction has been obtained via a strategy that examines molecules appended with chiral auxiliary within achiral and chirally-modified zeolites. The latter approach yields products with diastereomeric excess >80%.
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Shailaja J, Sivaguru J, Ramamurthy V. Zeolite matrix assisted decomposition of singlet oxygen sensitizers during photooxidation. J Photochem Photobiol A Chem 2016. [DOI: 10.1016/j.jphotochem.2016.02.010] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Matsui Y, Oishi T, Ohta E, Ikeda H. Adiabatic process of higher electronically excited states: luminescence from an excited state biradical generated by irradiation of benzophenone-substituted cyclopropanes. J PHYS ORG CHEM 2016. [DOI: 10.1002/poc.3636] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Yasunori Matsui
- Department of Applied Chemistry, Graduate School of Engineering; Osaka Prefecture University; Sakai Osaka 599-8531 Japan
- The Research Institute for Molecular Electronic Devices (RIMED); Osaka Prefecture University; Sakai Osaka 599-8531 Japan
| | - Toru Oishi
- Department of Applied Chemistry, Graduate School of Engineering; Osaka Prefecture University; Sakai Osaka 599-8531 Japan
| | - Eisuke Ohta
- Department of Applied Chemistry, Graduate School of Engineering; Osaka Prefecture University; Sakai Osaka 599-8531 Japan
- The Research Institute for Molecular Electronic Devices (RIMED); Osaka Prefecture University; Sakai Osaka 599-8531 Japan
| | - Hiroshi Ikeda
- Department of Applied Chemistry, Graduate School of Engineering; Osaka Prefecture University; Sakai Osaka 599-8531 Japan
- The Research Institute for Molecular Electronic Devices (RIMED); Osaka Prefecture University; Sakai Osaka 599-8531 Japan
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Ramamurthy V, Mondal B. Supramolecular photochemistry concepts highlighted with select examples. JOURNAL OF PHOTOCHEMISTRY AND PHOTOBIOLOGY C-PHOTOCHEMISTRY REVIEWS 2015. [DOI: 10.1016/j.jphotochemrev.2015.04.002] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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Ayitou AJL, Clay A, Kumarasamy E, Jockusch S, Sivaguru J. Enantiospecific photochemical 6π-ring closure of α-substituted atropisomeric acrylanilides – role of alkali metal ions. Photochem Photobiol Sci 2014; 13:141-4. [DOI: 10.1039/c3pp50278c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Bürli RW, Luckhurst CA, Aziz O, Matthews KL, Yates D, Lyons KA, Beconi M, McAllister G, Breccia P, Stott AJ, Penrose SD, Wall M, Lamers M, Leonard P, Müller I, Richardson CM, Jarvis R, Stones L, Hughes S, Wishart G, Haughan AF, O'Connell C, Mead T, McNeil H, Vann J, Mangette J, Maillard M, Beaumont V, Munoz-Sanjuan I, Dominguez C. Design, synthesis, and biological evaluation of potent and selective class IIa histone deacetylase (HDAC) inhibitors as a potential therapy for Huntington's disease. J Med Chem 2013; 56:9934-54. [PMID: 24261862 DOI: 10.1021/jm4011884] [Citation(s) in RCA: 114] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/17/2022]
Abstract
Inhibition of class IIa histone deacetylase (HDAC) enzymes have been suggested as a therapeutic strategy for a number of diseases, including Huntington's disease. Catalytic-site small molecule inhibitors of the class IIa HDAC4, -5, -7, and -9 were developed. These trisubstituted diarylcyclopropanehydroxamic acids were designed to exploit a lower pocket that is characteristic for the class IIa HDACs, not present in other HDAC classes. Selected inhibitors were cocrystallized with the catalytic domain of human HDAC4. We describe the first HDAC4 catalytic domain crystal structure in a "closed-loop" form, which in our view represents the biologically relevant conformation. We have demonstrated that these molecules can differentiate class IIa HDACs from class I and class IIb subtypes. They exhibited pharmacokinetic properties that should enable the assessment of their therapeutic benefit in both peripheral and CNS disorders. These selective inhibitors provide a means for evaluating potential efficacy in preclinical models in vivo.
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Affiliation(s)
- Roland W Bürli
- BioFocus , Chesterford Research Park, Saffron Walden, Essex, CB10 1XL, United Kingdom
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11
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Bhella SS, Elango M, Ishar MPS. Design, synthesis and conformational analysis of turn inducer cyclopropane scaffolds: microwave assisted amidation of unactivated esters on catalytic solid support to obtain γ-turn mimic scaffolds. Tetrahedron 2009. [DOI: 10.1016/j.tet.2008.10.058] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Solomon MR, Sivaguru J, Jockusch S, Adam W, Turro NJ. Physical and chemical quenching rates and their influence on stereoselective photooxygenation of oxazolidinone-functionalized enecarbamates. Photochem Photobiol Sci 2009; 8:912-5. [DOI: 10.1039/b903848e] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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13
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Muehling O, Wessig P. Stereoselective Synthesis of Cyclopropanes Based on a 1,2-Chirality Transfer. Chemistry 2008; 14:7951-60. [DOI: 10.1002/chem.200801002] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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14
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Fraile JM, García JI, Jiménez-Osés G, Mayoral JA, Roldán M. Surface Confinement Effects on Enantioselective Cyclopropanation. Reactions with Supported Chiral 8-Oxazolinylquinoline−Copper Complexes. Organometallics 2008. [DOI: 10.1021/om7010408] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Affiliation(s)
- José M. Fraile
- Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón and Instituto Universitario de Catálisis Homogénea, Facultad de Ciencias, Universidad de Zaragoza−CSIC, E-50009 Zaragoza, Spain
| | - José I. García
- Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón and Instituto Universitario de Catálisis Homogénea, Facultad de Ciencias, Universidad de Zaragoza−CSIC, E-50009 Zaragoza, Spain
| | - Gonzalo Jiménez-Osés
- Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón and Instituto Universitario de Catálisis Homogénea, Facultad de Ciencias, Universidad de Zaragoza−CSIC, E-50009 Zaragoza, Spain
| | - José A. Mayoral
- Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón and Instituto Universitario de Catálisis Homogénea, Facultad de Ciencias, Universidad de Zaragoza−CSIC, E-50009 Zaragoza, Spain
| | - Marta Roldán
- Departamento de Química Orgánica, Instituto de Ciencia de Materiales de Aragón and Instituto Universitario de Catálisis Homogénea, Facultad de Ciencias, Universidad de Zaragoza−CSIC, E-50009 Zaragoza, Spain
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15
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Arumugam S. Nafion as an efficient reaction medium for diastereoselective photochemical reactions. Tetrahedron Lett 2008. [DOI: 10.1016/j.tetlet.2008.02.041] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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16
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Solomon M, Sivaguru J, Jockusch S, Adam W, Turro NJ. Vibrational deactivation of singlet oxygen: does it play a role in stereoselectivity during photooxygenation? Photochem Photobiol Sci 2008; 7:531-3. [DOI: 10.1039/b719387d] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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17
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Wang Y, Ma J, Inagaki S. Stable silicon-centered localized singlet 1,3-diradicals XSi(GeY2)2SiX: theoretical predictions. J PHYS ORG CHEM 2007. [DOI: 10.1002/poc.1221] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Sivasubramanian K, Kaanumalle LS, Uppili S, Ramamurthy V. Value of zeolites in asymmetric induction during photocyclization of pyridones, cyclohexadienones and naphthalenones. Org Biomol Chem 2007; 5:1569-76. [PMID: 17571186 DOI: 10.1039/b702572f] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Two strategies, namely chiral inductor and chiral auxiliary approaches, have been examined within zeolites with the aim of achieving asymmetric induction during the photocyclization of cyclohexadienone, naphthalenone and pyridone derivatives. Within zeolites, enantioselectivity as high as 55% and diastereoselectivity as high as 88% have been obtained. The observed stereoselectivities are significant given the fact that these reactions gave very little stereoselectivities in isotropic solution media. The results obtained on the photocyclization of dienones, naphthalenones and N-alkyl pyridones within zeolites compliment our earlier investigations on the photocyclization of tropolone derivatives, the geometric isomerization of 1,2-diphenylcyclopropanes and 2,3-diphenyl-1-benzoyl cyclopropanes, and the Norrish type II reaction of alpha-oxoamides, phenyl adamantyl ketones, phenyl norbornyl ketones and phenyl cyclohexyl ketones. With the help of these examples, we have established the importance of zeolite and its charge compensating cations in effecting asymmetric induction in photochemical reactions.
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Natarajan A, Ramamurthy V. Asymmetric induction during photocyclization of chiral and achiral α-oxoamides within achiral zeolites. Org Biomol Chem 2006; 4:4533-42. [PMID: 17268650 DOI: 10.1039/b611387g] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
The photochemistry of 31 alpha-oxoamides capable of undergoing gamma-hydrogen transfer has been examined within zeolites. These molecules, upon excitation, yield two products--a beta-lactam and oxazolidinone--in solution, both resulting from gamma-hydrogen transfer. While in benzene the major product is oxazolidinone, within an MY zeolite, the main product is a beta-lactam. In this investigation, we have focused our attention on asymmetric induction in the formation of the beta-lactam product. Two approaches--using a chiral inductor and chiral auxiliary--have been employed. While in solution, in the presence of chiral inductors, achiral alpha-oxoamides yield beta-lactams with zero enantioselectivity; within zeolites, an ee of up to 44% has been achieved. Alpha-oxoamides appended with a chiral auxiliary gave beta-lactams with less than 5% diastereoselectivity in solution while within zeolites, the same alpha-oxoamides gave the products with de's of up to 83%. Such a remarkable influence of zeolites is attributed to an alkali ion interaction with the reactant alpha-oxoamides and to the confined environment of the zeolite interior. At this stage, we have not been able to provide a model with predictive power and further work is needed to understand this valuable asymmetric induction strategy.
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Sivaguru J, Saito H, Solomon MR, Kaanumalle LS, Poon T, Jockusch S, Adam W, Ramamurthy V, Inoue Y, Turro NJ. Control of Chirality by Cations in Confined Spaces: Photooxidation of Enecarbamates Inside Zeolite Supercages†. Photochem Photobiol 2006; 82:123-31. [PMID: 16076247 DOI: 10.1562/2005-06-15-ra-573] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022]
Abstract
On photooxygenation of the optically active Z/E enecarbamates 1 (X = i-Pr) and 2 (X = Me) equipped with the oxazolidinone chiral auxiliary in methylene-blue (MB)-incorporated, alkali-metal (M = Li, Na, K, Cs, Rb), exchanged Y-type zeolites (MY-MB), oxidative cleavage of the alkenyl functionality releases the enantiomerically enriched methyldesoxybenzoin (MDB) product. The extent (%ee) and/or the sense (R or S) of the stereoselectivity in the formation of the MDB product depends on the choice of the alkyl substiuent (i-Pr or Me) at the C-4 position of the oxazolidinone chiral auxiliary, the Z/E configuration of the alkene functionality in the enecarbamates, and the type of alkali metal in the zeolite. Most significantly-the highlight of this study-is the reversed sense (R or S) in the stereoselection when the photooxygenation is run in CDCl3 solution versus inside the MY-MB zeolite. As a mechanistic rationale for this novel stereochemical behavior, we propose the combined action of spatial confinement and metal-ion coordination (assessed by density-functional calculations) of the substrate within the zeolite supercage, both of which greatly reduce the freedom of the substrate and entropically manipulate the stereochemical outcome.
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Affiliation(s)
- J Sivaguru
- The Department of Chemistry, Columbia University, New York, NY, USA
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Furutani A, Katayama K, Uesima Y, Ogura M, Tobe Y, Kurosawa H, Tsutsumi K, Morimoto T, Kakiuchi K. Asymmetric [2+2] photocycloaddition of cycloalkenone–cyclodextrin complexes to ethylene. Chirality 2006; 18:217-21. [PMID: 16432915 DOI: 10.1002/chir.20232] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
The enantioselective [2+2] photocycloaddition of cycloalkenone-cyclodextrin complexes to ethylene was examined. Photoreaction of alpha-, beta-, and gamma-cyclodextrin complexes of various cyclohexenonecarboxylates and cyclopentenonecarboxylates in the presence of ethylene in the solid state or in aqueous suspension gave corresponding photocycloadducts with chiral induction.
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Affiliation(s)
- Akinori Furutani
- Graduate School of Materials Science, Nara Institute of Science and Technology (NAIST), Nara, Japan
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22
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Wang Y, Ma J, Inagaki S. Theoretical design of singlet localized σ-diradicals: C(MH2)3C (M=Si, Ge, Sn, Pb). Tetrahedron Lett 2005. [DOI: 10.1016/j.tetlet.2005.06.064] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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