51
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Diastereo- and enantioselective synthesis of anti-1,3-mercapto alcohols from α,β-unsaturated ketones via tandem Michael addition–MPV reduction. ACTA ACUST UNITED AC 2004. [DOI: 10.1016/j.tetasy.2004.01.020] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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52
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Aggarwal VK, Alonso E, Bae I, Hynd G, Lydon KM, Palmer MJ, Patel M, Porcelloni M, Richardson J, Stenson RA, Studley JR, Vasse JL, Winn CL. A new protocol for the in situ generation of aromatic, heteroaromatic, and unsaturated diazo compounds and its application in catalytic and asymmetric epoxidation of carbonyl compounds. Extensive studies to map out scope and limitations, and rationalization of diastereo- and enantioselectivities. J Am Chem Soc 2003; 125:10926-40. [PMID: 12952474 DOI: 10.1021/ja034606+] [Citation(s) in RCA: 161] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A variety of metalated tosylhydrazone salts derived from benzaldehyde have been prepared and were reacted with benzaldehyde in the presence of tetrahydrothiophene (THT) (20 mol %) and Rh(2)(OAc)(4) (1 mol %) to give stilbene oxide. Of the lithium, sodium, and potassium salts tested, the sodium salt was found to give the highest yield and selectivity. This study was extended to a wide variety of aromatic, heteroaromatic, aliphatic, alpha,beta-unsaturated, and acetylenic aldehydes and to ketones. On the whole, high yields of epoxides with moderate to very high diastereoselectivities were observed. A broad range of tosylhydrazone salts derived from aromatic, heteroaromatic, and alpha,beta-unsaturated aldehydes was also examined using the same protocol in reactions with benzaldehyde, and again, good yields and high diastereoselectivities were observed in most cases. Thus, a general process for the in situ generation of diazo compounds from tosylhydrazone sodium salts has been established and applied in sulfur-ylide mediated epoxidation reactions. The chiral, camphor-derived, [2.2.1] bicyclic sulfide 7 was employed (at 5-20 mol % loading) to render the above processes asymmetric with a range of carbonyl compounds and tosylhydrazone sodium salts. Benzaldehyde tosylhydrazone sodium salt gave enantioselectivities of 91 +/- 3% ee and high levels of diastereoselectivity with a range of aldehydes. However, tosylhydrazone salts derived from a range of carbonyl compounds gave more variable selectivities. Although those salts derived from electron-rich or neutral aldehydes gave high enantioselectivities, those derived from electron-deficient or hindered aromatic aldehydes gave somewhat reduced enantioselectivities. Using alpha,beta-unsaturated hydrazones, chiral sulfide 7 gave epoxides with high diastereoselectivities, but only moderate yields were achieved (12-56%) with varying degrees of enantioselectivity. A study of solvent effects showed that, while the impact on enantioselectivity was small, the efficiency of diazo compound generation was influenced, and CH(3)CN and 1,4-dioxane emerged as the optimum solvents. A general rationalization of the factors that influence both relative and absolute stereochemistry for all of the different substrates is provided. Reversibility in formation of the betaine intermediate is an important issue in the control of diastereoselectivity. Hence, where low diastereocontrol was observed, the results have been rationalized in terms of the factors that contribute to the reduced reversion of the syn betaine back to the original starting materials. The enantioselectivity is governed by ylide conformation, facial selectivity in the ylide reaction, and, again, the degree of reversibility in betaine formation. From experimental evidence and calculations, it has been shown that sulfide 7 gives almost complete control of facial selectivity, and, hence, it is the ylide conformation and degree of reversibility that are responsible for the enantioselectivity observed. A simple test has been developed to ascertain whether the reduced enantioselectivity observed in particular cases is due to poor control in ylide conformation or due to partial reversibility in the formation of the betaine.
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Solladié-Cavallo A, Balaz M, Salisova M, Welter R. New 1,3-oxathianes derived from myrtenal: synthesis and reactivity. J Org Chem 2003; 68:6619-26. [PMID: 12919025 DOI: 10.1021/jo034404w] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
2-Methyl- and 2-phenyl-substituted oxathianes derived from Myrtenal have been synthesized in satisfying yields. Lithiation of 2-methyl-substituted oxathiane could not be done, but lithiation of 2-phenyl-substituted and non-substituted oxathianes could be performed with s-BuLi. Quenching with D(2)O, TMSCl, and/or a carbonyl compound always provides the equatorial product in consistency with a prefered equatorial orientation of the lithium in the lithiated derivatives. A model is proposed to rationalize the diastereoselectivities observed at C5' during reaction of aldehydes with lithiated non-substituted oxathiane. The model is based on the hypothesis that the lithium, being linked simultaneously to the carbon and the oxygen, is shifted toward the oxygen side, making the steric hindrance of this side more effective. Dimeric side products were observed during formation of these oxathianes (condensation of various aldehydes with the corresponding hydroxythiol), which had not been reported for other oxathianes (derived from pulegone and/or camphorsulfonic acid).
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54
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Verdaguer X, Pericàs MA, Riera A, Maestro MA, Mahía J. Design of New Hemilabile (P,S) Ligands for the Highly Diastereoselective Coordination to Alkyne Dicobalt Complexes: Application to the Asymmetric Intermolecular Pauson−Khand Reaction. Organometallics 2003. [DOI: 10.1021/om021008f] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xavier Verdaguer
- Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Parc Científic de Barcelona, and Departament de Química Orgànica, Universitat de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain, and Servicios Xerais de Apoio á Investigación, Campus Zapateria, s/n, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Miquel A. Pericàs
- Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Parc Científic de Barcelona, and Departament de Química Orgànica, Universitat de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain, and Servicios Xerais de Apoio á Investigación, Campus Zapateria, s/n, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Antoni Riera
- Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Parc Científic de Barcelona, and Departament de Química Orgànica, Universitat de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain, and Servicios Xerais de Apoio á Investigación, Campus Zapateria, s/n, Universidade da Coruña, E-15071 A Coruña, Spain
| | - Miguel A. Maestro
- Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Parc Científic de Barcelona, and Departament de Química Orgànica, Universitat de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain, and Servicios Xerais de Apoio á Investigación, Campus Zapateria, s/n, Universidade da Coruña, E-15071 A Coruña, Spain
| | - José Mahía
- Unitat de Recerca en Síntesi Asimètrica (URSA-PCB), Parc Científic de Barcelona, and Departament de Química Orgànica, Universitat de Barcelona, Josep Samitier 1-5, E-08028 Barcelona, Spain, and Servicios Xerais de Apoio á Investigación, Campus Zapateria, s/n, Universidade da Coruña, E-15071 A Coruña, Spain
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55
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Despagnet-Ayoub E, Solé S, Gornitzka H, Rozhenko AB, Schoeller WW, Bourissou D, Bertrand G. (Phosphino)(aryl)carbenes: effect of aryl substituents on their stabilization mode. J Am Chem Soc 2003; 125:124-30. [PMID: 12515513 DOI: 10.1021/ja0281986] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
A broad range of (phosphino)(aryl)carbenes, 1b-d, 10a,b, and 14a,b, were prepared by photolysis of their diazo precursors. The influence of the steric and electronic properties of the aryl ring on the structure and stability of these carbenes was studied both experimentally and theoretically. Among the different stabilization modes investigated, those featuring an acceptor as well as a spectator aryl substituent result in stable or at least persistent carbenes that could be completely characterized by classical spectroscopic methods. In marked contrast, the new substitution pattern featuring a donor aryl ring results in a very fleeting carbene.
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Affiliation(s)
- Emmanuelle Despagnet-Ayoub
- Laboratoire d'Hétérochimie Fondamentale et Appliquée du CNRS (UMR 5069), Université Paul Sabatier, 118 route de Narbonne, F-31062 Toulouse Cedex 04, France
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56
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Zanardi J, Lamazure D, Minière S, Reboul V, Metzner P. First enantioselective synthesis of vinyl oxiranes from aldehydes and ylides generated from allyl halides and chiral sulfides. J Org Chem 2002; 67:9083-6. [PMID: 12467434 DOI: 10.1021/jo026085z] [Citation(s) in RCA: 49] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Asymmetric allylidenation of aldehydes with sulfur ylides is possible with proper substitution of the initial sulfide, to avoid the [2,3] sigmatropic rearrangement of the unsaturated ylides. One-pot reaction of (2R,5R)-dimethylthiolane with allyl halides, aldehydes, and sodium hydroxide in tert-butyl alcohol affords vinyl oxiranes in good yields. Enantiomeric excesses up to 90% and trans selectivities have been achieved with methallyl-type halides.
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Affiliation(s)
- Jacques Zanardi
- Laboratoire de Chimie Moléculaire et Thio-organique (UMR CNRS 6507), ISMRA-Université de Caen, 6 Boulevard du Maréchal Juin, F-14050 Caen, France
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57
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58
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Aggarwal VK, Harvey JN, Richardson J. Unraveling the mechanism of epoxide formation from sulfur ylides and aldehydes. J Am Chem Soc 2002; 124:5747-56. [PMID: 12010049 DOI: 10.1021/ja025633n] [Citation(s) in RCA: 108] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Sulfur ylides R(2)S(+)-C(-)HR' react with aldehydes R' '-CHO to form epoxides, predominantly as the trans isomers, in a synthetically useful reaction which is increasingly used in its asymmetric variant with chiral sulfides. The mechanisms of the "model" reaction (R = Me, R' = R' ' = H) and the reaction forming stilbene oxide (R = Me, R' = R' ' = Ph) have been studied in detail using density functional theory, the B3LYP density functional, and flexible basis sets. It has been shown that for this reaction involving highly polar intermediates, continuum solvation models need to be used throughout to obtain reasonable results. For the reaction of benzaldehyde with dimethylsulfonium benzylide, the key steps are shown to be quasi [2 + 2] addition of the ylide to the aldehyde to form a betaine R'-CH(S(+)Me(2))-CH(O(-))-R' ' in which the charged groups are gauche to one another, and torsional rotation around the C-C single bond of the betaine to form its rotamer with the two charged groups anti. The final step, elimination of sulfide from this second rotamer of the betaine, is found to be facile. In the case of the anti pathway, leading to trans-stilbene epoxide, the initial addition is found to be rate-determining, whereas for the diastereomeric syn pathway, leading to the cis-epoxide, it is instead the torsional rotation which is slowest. These results are in excellent agreement with experiment, unlike previous computational work. The unexpected and apparently unprecedented (for C-C bond-forming reactions) importance of the torsional rotation step, especially in the syn case, is due to the fact that all the barriers involved are low-lying. This novel picture of the mechanism provides a sound basis for the future development of chiral sulfides for enantioselective epoxide synthesis.
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Affiliation(s)
- Varinder K Aggarwal
- School of Chemistry, University of Bristol, Cantock's Close, Bristol BS8 1TS, U.K
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59
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Catasús M, Moyano A, Aggarwal VK. Sulphur ylide-mediated stereoselective synthesis of a stable ferrocenyl epoxide. Tetrahedron Lett 2002. [DOI: 10.1016/s0040-4039(02)00578-6] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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60
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Nakamura S, Furutani A, Toru T. Highly Enantioselective Reaction of α-Lithio 2-Quinolyl Sulfide Using Chiral Bis(oxazoline)s: A New Synthesis of Enantioenriched Thiols. European J Org Chem 2002. [DOI: 10.1002/1099-0690(200205)2002:10<1690::aid-ejoc1690>3.0.co;2-9] [Citation(s) in RCA: 38] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
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61
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Martı́nez-Ramos F, Vargas-Dı́az ME, Chacón-Garcı́a L, Tamariz J, Joseph-Nathan P, Zepeda L. Highly diastereoselective nucleophilic additions using a novel myrtenal-derived oxathiane as a chiral auxiliary. ACTA ACUST UNITED AC 2001. [DOI: 10.1016/s0957-4166(01)00545-6] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
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62
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63
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Abstract
The last few years have witnessed a spectacular advancement in new catalytic methods based on metal-free organic molecules. In many cases, these small compounds give rise to extremely high enantioselectivities. Preparative advantages are notable: usually the reactions can be performed under an aerobic atmosphere with wet solvents. The catalysts are inexpensive and they are often more stable than enzymes or other bioorganic catalysts. Also, these small organic molecules can be anchored to a solid support and reused more conveniently than organometallic/bioorganic analogues, and show promising adaptability to high-throughput screening and process chemistry. Herein we focus on four different domains in which organocatalysis has made major advances: 1) The activation of the reaction based on the nucleophilic/electrophilic properties of the catalysts. This type of catalysis has much in common with conventional Lewis acid/base activation by metal complexes. 2) Transformations in which the organic catalyst forms a reactive intermediate: the chiral catalyst is consumed in the reaction and requires regeneration in a parallel catalytic cycle. 3) Phase-transfer reactions: The chiral catalyst forms a host-guest complex with the substrate and shuttles between the standard organic solvent and the second phase (i.e. a solid, aqueous, or fluorous phase in which the organic transformation takes place). 4) Molecular-cavity-accelerated asymmetric transformations: the catalyst can select between competing substrates, depending on size and structure criteria. The rate acceleration of a given reaction is similar to the Lewis acid/base activation and is the consequence of the simultaneous action of different polar functions. Herein it is shown that organocatalysis complements rather than competes with current methods. It offers something conceptually novel and opens new horizons in synthesis.
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Affiliation(s)
- Peter I. Dalko
- Laboratoire de Recherches Organiques associé au CNRS, ESCPI 10 rue Vauquelin, 75231 Paris Cedex 05 (France)
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64
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65
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Zanardi J, Leriverend C, Aubert D, Julienne K, Metzner P. A catalytic cycle for the asymmetric synthesis of epoxides using sulfur ylides. J Org Chem 2001; 66:5620-3. [PMID: 11485494 DOI: 10.1021/jo015588m] [Citation(s) in RCA: 76] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- J Zanardi
- Laboratoire de Chimie Moléculaire et Thioorganique, UMR CNRS 6507, ISMRA-Université de Caen, 6 Boulevard du Maréchal Juin, 14050 Caen, France
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66
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Lebel H, Paquet V, Proulx C. Methylenation of Aldehydes: Transition Metal Catalyzed Formation of Salt-Free Phosphorus Ylides. Angew Chem Int Ed Engl 2001; 40:2887-2890. [DOI: 10.1002/1521-3773(20010803)40:15<2887::aid-anie2887>3.0.co;2-q] [Citation(s) in RCA: 87] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2001] [Revised: 05/07/2001] [Indexed: 11/08/2022]
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67
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Lebel H, Paquet V, Proulx C. Methylenation of Aldehydes: Transition Metal Catalyzed Formation of Salt-Free Phosphorus Ylides. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010803)113:15<2971::aid-ange2971>3.0.co;2-p] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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68
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Myllymäki VT, Lindvall MK, Koskinen AM. Computer-assisted discovery of novel amino acid derived sulfides for enantioselective epoxidation of aldehydes. Tetrahedron 2001. [DOI: 10.1016/s0040-4020(01)00396-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
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69
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Aggarwal VK, Alonso E, Hynd G, Lydon KM, Palmer MJ, Porcelloni M, Studley JR. Katalytische asymmetrische Epoxidierung von Aldehyden mit Schwefel-Yliden und in situ hergestellten Diazoverbindungen. Angew Chem Int Ed Engl 2001. [DOI: 10.1002/1521-3757(20010417)113:8<1479::aid-ange1479>3.0.co;2-u] [Citation(s) in RCA: 46] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
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70
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Aggarwal VK, Alonso E, Hynd G, Lydon KM, Palmer MJ, Porcelloni M, Studley JR. Catalytic Asymmetric Synthesis of Epoxides from Aldehydes Using Sulfur Ylides with In Situ Generation of Diazocompounds. Angew Chem Int Ed Engl 2001; 40:1430-1433. [PMID: 29712341 DOI: 10.1002/1521-3773(20010417)40:8<1430::aid-anie1430>3.0.co;2-w] [Citation(s) in RCA: 168] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2000] [Revised: 01/23/2001] [Indexed: 11/10/2022]
Abstract
A practical, general, and convergent route to epoxides with control of the relative and absolute stereochemistry has been achieved by generating the reactive intermediate (the diazo compound) in situ from tosylhydrazone salts (see scheme, PTC=phase-transfer catalyst, Ts=toluene-4-sulfonyl). High yields (58-82 %), high d.r. (88:12-98:2), and high ee values (87-94 %) have been obtained using a new class of stable chiral sulfides at low catalyst loading (5 mol %) and [Rh2 (OAc)4 ] (0.5 mol %).
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Affiliation(s)
- Varinder K Aggarwal
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - Emma Alonso
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - George Hynd
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - Kevin M Lydon
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - Matthew J Palmer
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - Marina Porcelloni
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
| | - John R Studley
- Department of Chemistry University of Sheffield Brook Hill, Sheffield, S3 7HF (UK)
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71
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A simple, user-friendly process for the homologation of aldehydes using tosylhydrazone salts. Tetrahedron Lett 2000. [DOI: 10.1016/s0040-4039(00)01856-6] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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72
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Nakamura S, Nakagawa R, Watanabe Y, Toru T. Highly Enantioselective Reactions of Configurationally Labile α-Thioorganolithiums Using Chiral Bis(oxazoline)s via Two Different Enantiodetermining Steps. J Am Chem Soc 2000. [DOI: 10.1021/ja0025191] [Citation(s) in RCA: 102] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Shuichi Nakamura
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Ryo Nakagawa
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Yoshihiko Watanabe
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
| | - Takeshi Toru
- Contribution from the Department of Applied Chemistry, Nagoya Institute of Technology, Gokiso, Showa-ku, Nagoya 466-8555, Japan
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73
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Garcı́a Martı́nez A, Teso Vilar E, Moreno Jiménez F, Garcı́a Amo M. Enantiospecific synthesis of substituted 1-norbornanesulfonic acids and 1-norbornanesulfenic and sulfonic acid derivatives. ACTA ACUST UNITED AC 2000. [DOI: 10.1016/s0957-4166(00)00122-1] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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74
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Zhang J, Koizumi T. OPTICALLY PURE CHALCOGENURANES: SYNTHESIS AND STEREOCHEMISTRY OF THEIR REACTIONS. PHOSPHORUS SULFUR 2000. [DOI: 10.1080/10426500008040525] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
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75
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Verdaguer X, Moyano A, Pericàs MA, Riera A, Alvarez-Larena A, Piniella JF. Alkyne Dicobalt Carbonyl Complexes with Sulfide Ligands. Synthesis, Crystal Structure, and Dynamic Behavior. Organometallics 1999. [DOI: 10.1021/om9903036] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
- Xavier Verdaguer
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Albert Moyano
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Miquel A. Pericàs
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Antoni Riera
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Angel Alvarez-Larena
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
| | - Joan-F. Piniella
- Unitat de Recerca en Síntesi Asimètrica, Departament de Química Orgànica, Universitat de Barcelona, c/ Martí i Franquès, 1-11, 08028 Barcelona, Spain, and Unitat de Cristal·lografia, Facultat de Ciències, Universitat Autònoma de Barcelona, 08193 Barcelona, Spain
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76
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77
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Lindvall MK, Koskinen AMP. Origins of Stereoselectivity in the Corey-Chaykovsky Reaction. Insights from Quantum Chemistry. J Org Chem 1999; 64:4596-4606. [PMID: 11674528 DOI: 10.1021/jo9818935] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Reaction pathways of the Corey-Chaykovsky epoxidation reaction have been compared quantum chemically. Of the concerted, torsional rotation and anti addition pathways the latter two were found to be favored both in the gas phase and in CH(2)Cl(2) in a model system. Several theoretically previously uncharacterized stationary points were located, and selective solvent effects were observed. On the anti addition pathway the C-C bond formation transition state A, suitably substituted to allow comparison with published experimental data, was able to predict both the absolute stereochemistry of the main product and, qualitatively, the distribution of its other stereoisomers. The quantum chemical protocol reported here is useful in designing new sulfides for the Corey-Chaykovsky reaction.
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Affiliation(s)
- Mika K. Lindvall
- Department of Chemistry, University of Oulu, P.O. Box 3000, FIN-90401 Oulu, Finland
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78
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Cieplak AS. Inductive and Resonance Effects of Substituents on pi-Face Selection. Chem Rev 1999; 99:1265-336. [PMID: 11749447 DOI: 10.1021/cr980381n] [Citation(s) in RCA: 129] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- A S Cieplak
- Department of Chemistry, Yale University, New Haven, Connecticut 06517, and Department of Chemistry, State University of New York at Stony Brook, Stony Brook, New York 11794
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Chapter 4.1 Three-membered ring systems. ACTA ACUST UNITED AC 1999. [DOI: 10.1016/s0959-6380(99)80006-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/05/2023]
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