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Wang Y, Du B, Sha W, Mei H, Han J, Pan Y. Transition-metal-free oxidative reaction of hydrazines and potassium metabisulfite for preparation of sulfonohydrazides. Org Chem Front 2017. [DOI: 10.1039/c7qo00168a] [Citation(s) in RCA: 61] [Impact Index Per Article: 8.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A coupling reaction for the synthesis of sulfonohydrazides from two types of hydrazines and K2S2O5 under air was developed.
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Affiliation(s)
- Yang Wang
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
| | - Bingnan Du
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
| | - Wanxing Sha
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
| | - Haibo Mei
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
| | - Jianlin Han
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
| | - Yi Pan
- School of Chemistry and Chemical Engineering
- State Key Laboratory of Coordination Chemistry
- Nanjing University
- Nanjing
- China
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2
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Abstract
Recent advances in the insertion of sulfur dioxide under transition metal catalysis or metal-free conditions via a radical process are presented.
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Affiliation(s)
- Gang Liu
- Jiangxi Key Laboratory of Organic Chemistry
- Jiangxi Science & Technology Normal University
- Nanchang 330013
- China
| | - Congbin Fan
- Jiangxi Key Laboratory of Organic Chemistry
- Jiangxi Science & Technology Normal University
- Nanchang 330013
- China
- Department of Chemistry
| | - Jie Wu
- Department of Chemistry
- Fudan University
- Shanghai 200433
- China
- State Key Laboratory of Organometallic Chemistry
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3
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Ye S, Wang H, Xiao Q, Ding Q, Wu J. Aminosulfonylation of Arenes, Sulfur Dioxide, and Hydrazines Cocatalyzed by Gold(III) Chloride and Palladium Acetate. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400334] [Citation(s) in RCA: 67] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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4
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Meruva SB, Mekala R, Raghunadh A, Raghavendra Rao K, Dahanukar VH, Pratap T, Syam Kumar U, Dubey P. Synthesis of tetrahedral diarylheptanoid ent-diospongin A and epimer-diospongin B by employing Julia–Kocienski olefination. Tetrahedron Lett 2014. [DOI: 10.1016/j.tetlet.2014.06.112] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
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5
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6
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Ye S, Wu J. A palladium-catalyzed three-component coupling of arylboronic acids, sulfur dioxide and hydrazines. Chem Commun (Camb) 2012; 48:7753-5. [DOI: 10.1039/c2cc33725h] [Citation(s) in RCA: 122] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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7
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Ye S, Wu J. A palladium-catalyzed reaction of aryl halides, potassium metabisulfite, and hydrazines. Chem Commun (Camb) 2012; 48:10037-9. [DOI: 10.1039/c2cc34957d] [Citation(s) in RCA: 150] [Impact Index Per Article: 12.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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8
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Reddy PV, Veyron A, Koos P, Bayle A, Greene AE, Delair P. Approach to the hyacinthacines: first non-chiral pool synthesis of (+)-hyacinthacine A1. Org Biomol Chem 2008; 6:1170-2. [DOI: 10.1039/b800445e] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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9
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Abstract
At low temperature and in the presence of an acid catalyst, SO2 adds to 1,3-dienes equilibrating with the corresponding 3,6-dihydro-1,2-oxathiin-2-oxides (sultines). These compounds are unstable above -60 °C and equilibrate with the more stable 2,5-dihydrothiophene 1,1-dioxides (sulfolenes). The hetero-Diels-Alder additions of SO2 are suprafacial and follow the Alder endo rule. The sultines derived from 1-oxy-substituted and 1,3-dioxy-disubstituted 1,3-dienes cannot be observed at -100 °C but are believed to be formed faster than the corresponding sulfolenes. In the presence of acid catalysts, the 6-oxy-substituted sultines equilibrate with zwitterionic species that react with electron-rich alkenes such as enoxysilanes and allylsilanes, generating β,γ-unsaturated silyl sulfinates that can be desilylated and desulfinylated to generate polypropionate fragments containing up to three contiguous stereogenic centers and an (E)-alkene unit. Alternatively, the silyl sulfinates can be reacted with electrophiles to generate polyfunctional sulfones (one-pot, four-component synthesis of sulfones), or oxidized into sulfonyl chlorides and reacted with amines, then realizing a one-pot, four-component synthesis of polyfunctional sulfonamides. Using enantiomerically enriched dienes such as 1-[(R)- or 1-(S)-phenylethyloxy]-2-methyl-(E,E)-penta-1,3-dien-3-yl isobutyrate, derived from inexpensive (R)- or (S)-1-phenylethanol, enantiomerically enriched stereotriads are obtained in one-pot operations. The latter are ready for further chain elongation. This has permitted the development of expeditious total asymmetric syntheses of important natural products of biological interest such as the baconipyrones, rifamycin S, and apoptolidin A.
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10
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Vogel P, Turks M, Bouchez L, Marković D, Varela-Alvarez A, Sordo JA. New organic chemistry of sulfur dioxide. Acc Chem Res 2007; 40:931-42. [PMID: 17685582 DOI: 10.1021/ar700096h] [Citation(s) in RCA: 100] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Simple 1,3-dienes undergo highly stereoselective hetero-Diels-Alder additions with SO2 at low temperature giving sultines. These reactions that are faster than the more exothermic cheletropic additions of SO2-producing sulfolenes. This has led to the invention of a new C-C bond-forming reaction combining electron-rich dienes and alkenes with SO2. The reaction cascade has been exploited to develop combinatorial, one-pot, four-component syntheses of polyfunctional sulfones, sulfonamides, and sulfonic esters. It also allows us to generate, in one-pot operations, enantiomerically enriched polypropionate fragments containing up to three contiguous stereogenic centers and a (E)-alkene unit. These fragments can be used directly in further C-C bond-forming reactions, such as cross-aldol condensations, thus permitting the expeditious construction of complicated natural products of biological interest (e.g., Baconipyrones, Rifamycin S, Apoptolidinone) and analogues. New ene reactions of SO2 have also been discovered; they open new avenues to organic synthesis.
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Affiliation(s)
- Pierre Vogel
- Laboratoire de glycochimie et synthèse asymétrique (LGSA), Ecole Polytechnique Fédérale de Lausanne (EPFL), Batochime, CH 1015 Lausanne, Switzerland.
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11
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Kar A, Sayyed IA, Lo WF, Kaiser HM, Beller M, Tse MK. A general copper-catalyzed sulfonylation of arylboronic acids. Org Lett 2007; 9:3405-8. [PMID: 17655315 DOI: 10.1021/ol071396n] [Citation(s) in RCA: 133] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A general copper-catalyzed method for the sulfonylation of arylboronic acids with sulfinate salts is described. A variety of alkyl-aryl, diaryl, and alkyl-heteroaryl sulfones were synthesized in good yield.
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Affiliation(s)
- Anirban Kar
- Leibniz-Institut für Katalyse e.V. an der Universität Rostock, Albert-Einstein-Str. 29a, D-18059 Rostock, Germany
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12
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Kuethe JT, Marcoux JF, Wong A, Wu J, Hillier MC, Dormer PG, Davies IW, Hughes DL. Stereoselective Preparation of a Cyclopentane-Based NK1 Receptor Antagonist Bearing an Unsymmetrically Substituted Sec−Sec Ether. J Org Chem 2006; 71:7378-90. [PMID: 16958533 DOI: 10.1021/jo061268x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
A highly efficient synthesis of the potent and selective NK-1 receptor antagonist 1 is described. The key transformation involved the etherification reaction between cyclopentanol 12 and chiral imidate 30 which was catalyzed by HBF4 to initially give ether 14 as a 17:1 mixture of diastereomers and in 75% combined yield. The diastereoselectivity was upgraded to 109:1 by crystallization of the triethylamine solvate 44 which was isolated in 54% yield from 12. Mechanistic studies confirmed that the etherification reaction proceeds through an unprecedented S(N)2 reaction pathway under typical S(N)1 reaction conditions.
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Affiliation(s)
- Jeffrey T Kuethe
- Department of Process Research, Merck and Company, Incorporated, P.O. Box 2000, Rahway, New Jersey 07065, USA.
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13
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Craita C, Bouchez L, Turks M, Huang X, Fonquerne F, Murcia MC, Vogel P. Total Synthesis of Polypropionate Natural Products: Application of New Sulfur Dioxide Chemistry. PHOSPHORUS SULFUR 2006. [DOI: 10.1080/10426500590910828] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- C. Craita
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - L. Bouchez
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - M. Turks
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - X. Huang
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - F. Fonquerne
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - M. C. Murcia
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
| | - P. Vogel
- a Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology Lausanne , Lausanne-Dorigny, Switzerland
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14
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Ramón DJ, Yus M. Asymmetric multicomponent reactions (AMCRs): the new frontier. Angew Chem Int Ed Engl 2006; 44:1602-34. [PMID: 15719349 DOI: 10.1002/anie.200460548] [Citation(s) in RCA: 1405] [Impact Index Per Article: 78.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Asymmetric multicomponent reactions involve the preparation of chiral compounds by the reaction of three or more reagents added simultaneously. This kind of addition and reaction has some advantages over classic divergent reaction strategies, such as lower costs, time, and energy, as well as environmentally friendlier aspects. All these advantages, together with the high level of stereoselectivity attained in some of these reactions, will force chemists in industry as in academia to adopt this new strategy of synthesis, or at least to consider it as a viable option. The positive aspects as well as the drawbacks of this strategy are discussed in this Review.
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Affiliation(s)
- Diego J Ramón
- Instituto de Síntesis Orgánica y Departamento de Química Orgánica, Facultad de Ciencias, Universidad de Alicante, Apdo. 99, 03080-Alicante, Spain
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15
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Bouchez LC, Turks M, Dubbaka SR, Fonquerne F, Craita C, Laclef S, Vogel P. Sulfur dioxide mediated one-pot, four-component synthesis of polyfunctional sulfones and sulfonamides, including medium-ring cyclic derivatives. Tetrahedron 2005. [DOI: 10.1016/j.tet.2005.08.067] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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16
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Ramón DJ, Yus M. Neue Entwicklungen in der asymmetrischen Mehrkomponenten-Reaktion. Angew Chem Int Ed Engl 2005. [DOI: 10.1002/ange.200460548] [Citation(s) in RCA: 352] [Impact Index Per Article: 18.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
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17
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Bouchez LC, Craita C, Vogel P. Sulfur Dioxide-Mediated Syntheses of Polyfunctional Alkenes and (E,Z)- and (E,E)-2,4-Dien-1-ones. Org Lett 2005; 7:897-900. [PMID: 15727469 DOI: 10.1021/ol050006z] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Efficient methods for the stereoselective synthesis of polyfunctional (E)- and (Z)-alkenes and conjugated (E,E)- and (E,Z)-dienones are presented. They rely upon one-pot, four-component processes that condense 1-oxy-1,3-dienes, silyl enol ethers, SO2, and carbon electrophiles. [structure: see text]
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Affiliation(s)
- Laure C Bouchez
- Laboratoire de Glycochimie et de Synthèse Asymétrique (LGSA), BCH, Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland
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18
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Turks M, Huang X, Vogel P. Expeditious Asymmetric Synthesis of a Stereoheptad Corresponding to the C(19)-C(27)-Ansa Chain of Rifamycins: Formal Total Synthesis of Rifamycin S. Chemistry 2005; 11:465-76. [PMID: 15551311 DOI: 10.1002/chem.200400825] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
In the presence of sulfur dioxide and an acid promoter, (-)-(1E,3Z)-2-methyl-1-((1S)-1-phenylethoxy)penta-1,3-dien-3-yl isobutyrate reacts with (Z)-3-(trimethylsilyloxy)pent-2-ene giving a silyl sulfinate intermediate that undergoes, in the presence of palladium catalyst, a desilylation and retro-ene elimination of SO(2) with formation of (-)-(1Z,2S,3R,4S)-1-ethylidene-2,4-dimethyl-5-oxo-3-((1S)-1-phenylethoxy)-heptyl isobutyrate as major product. This ethyl ketone undergoes cross-aldol reaction with (2S)-2-methyl-3-[(tert-butyldimethylsilyl)oxy]propanal giving an aldol that is reduced into a stereoheptad corresponding to the C(19)-C(27)-segment of Rifamycins with high diastereoselectivity and enantiomeric excess.
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Affiliation(s)
- Māris Turks
- Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology, BCH 1015, Lausanne-Dorigny, Switzerland
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19
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Bouchez LC, Dubbaka SR, Turks M, Vogel P. Sulfur Dioxide Mediated One-Pot, Three- and Four-Component Syntheses of Polyfunctional Sulfonamides and Sulfonic Esters: Study of the Stereoselectivity of the Ene Reaction of Sulfur Dioxide. J Org Chem 2004; 69:6413-8. [PMID: 15357602 DOI: 10.1021/jo049047j] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The ene reaction of sulfur dioxide with enoxysilanes or with allylsilanes generates silyl sulfinates that can be brominated (Br(2) or NBS) or chlorinated (NCS or Cl(2)) to produce the corresponding sulfonyl halides. They react with primary and secondary amines or alcohols to give the corresponding sulfonamides and sulfonic esters, respectively. The hetero-Diels-Alder addition of sulfur dioxide to 1-oxy- or 1,3-dioxy-1,3-dienes generates zwitterions that add to enoxysilanes or allylsilanes giving silyl sulfinates that can be converted in situ into polyfunctional sulfonamides or sulfonic esters. This realizes quick access to libraries of complicated sulfonamides and sulfonic esters applying one-pot, three- and four-component methods.
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Affiliation(s)
- Laure C Bouchez
- Institute of Chemical Sciences and Engineering, Swiss Federal Institute of Technology (EPFL), BCH, CH-1015 Lausanne-Dorigny, Switzerland
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20
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Turks M, Murcia MC, Scopelliti R, Vogel P. First Asymmetric Synthesis of the Cyclohexanone Subunit of Baconipyrones A and B. Revision of Its Structure. Org Lett 2004; 6:3031-4. [PMID: 15330580 DOI: 10.1021/ol048988f] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] An asymmetric synthesis of the 3,5-dihydroxycyclohexanone subunit of baconipyrones A and B, as well as that of the hydroxydiketone subunit of baconipyrones C and D ((-)-(4S,6S)-4,6-dimethyl-5-hydroxynonan-3,7-dione), is described. Key steps include sulfur dioxide-induced additions of enoxysilanes to 1,3-dioxy-1,3-dienes, followed by retro-ene desulfitations (retro-ene elimination of SO(2)).
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Affiliation(s)
- Māris Turks
- Laboratory of Glycochemistry and Asymmetric Synthesis, BCH, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland
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21
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Huang X, Craita C, Vogel P. Palladium-Catalyzed Conversion of β,γ-Unsaturated Silyl Sulfinates into (E)-Alkenes: Asymmetric Synthesis of Polypropionate Fragments. J Org Chem 2004; 69:4272-5. [PMID: 15176859 DOI: 10.1021/jo0357622] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
At low temperature, 1-alkoxy-1,3-dienes add to sulfur dioxide activated by a Lewis or protic acid generating zwitterionic intermediates that can be quenched by enoxysilanes. The resulting beta,gamma-unsaturated silyl sulfinates can be desilylated by 1:1 Pd(OAc)(2)/PPh(3) catalyst, liberating the corresponding beta,gamma-unsaturated sulfinic acids that undergo smooth and highly stereoselective retro-ene eliminations of sulfur dioxide. The method has been applied to generate enantiomerically pure polypropionate fragments.
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Affiliation(s)
- Xiaogen Huang
- Laboratory of Glycochemistry and Asymmetric Synthesis, Swiss Federal Institute of Technology, EPFL-BCH, CH-1015 Lausanne-Dorigny, Switzerland
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22
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Turks M, Fonquerne F, Vogel P. Synthesis of Long-Chain Polyketide Fragments by Reaction of 1,3-Dioxy-1,3-dienes with Allylsilanes: Umpolung with Sulfur Dioxide. Org Lett 2004; 6:1053-6. [PMID: 15012098 DOI: 10.1021/ol0498646] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
[reaction: see text] In the presence of a Lewis or protic acid and at low temperature, 1,3-dioxy-1,3-dienes add to sulfur dioxide generating zwitterionic intermediates that can react with carbon nucleophiles such as allylsilanes. After a retro-ene elimination of SO(2), valuable polyketide precursors are obtained.
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Affiliation(s)
- Māris Turks
- Institute of Molecular and Biological Chemistry, Swiss Federal Institute of Technology (EPFL), BCH CH-1015 Lausanne, Switzerland
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23
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Monnat F, Vogel P, Rayón VM, Sordo JA. Ab initio and experimental studies on the hetero-Diels-Alder and cheletropic additions of sulfur dioxide to (E)-1-methoxybutadiene: a mechanism involving three molecules of SO(2). J Org Chem 2002; 67:1882-9. [PMID: 11895406 DOI: 10.1021/jo010998w] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Kinetics on the cheletropic addition of sulfur dioxide to (E)-1-methoxybutadiene (1) to give the corresponding sulfolene 2 (2-methoxy-2,5-dihydrothiophene-1,1-dioxide) gave the rate law d[2]/dt = k[1][SO(2)](x)() with x = 2.6 +/- 0.2 at 198 K. Under these conditions, no sultine 3 [(2RS,6RS)-6-methoxy-3,6-dihydro-1,2-oxathiin-2-oxide] resulting from a hetero-Diels-Alder addition was observed, and the cheletropic elimination 2 --> 1 + SO(2) did not occur. Ab initio and DFT quantum calculations confirmed that the cheletropic addition 1 + SO(2) --> 2 follows two parallel mechanisms, one involving two molecules of SO(2) and the transition structure with DeltaG(++) = 18.2 +/- 0.2 kcal/mol at 198 K (exptl); 22.5-22.7 kcal/mol [B3LYP/6-31G(d,p)], the other one involving three molecules of SO(2) with DeltaG(++) = 18.9 +/- 0.1 kcal/mol at 198 K (exptl); 19.7 kcal/mol [B3LYP/6-31G(d,p)]. The mechanism involving only one molecule of SO(2) in the transition structure requires a higher activation energy, DeltaG(++) = 25.2 kcal/mol [B3LYP/6-31G(d,p)]. Comparison of the geometries and energetics of the structures involved into the 1 + SO(2) --> 2, 3 and 1 + 2SO(2) --> 2, 3 + SO(2) reactions obtained by ab initio and DFT methods suggest that the latter calculation techniques can be used to study the cycloadditions of sulfur dioxide. The calculations predict that the hetero-Diels-Alder addition 1 + SO(2) --> 3 also prefers a mechanism in which three molecules of SO(2) are involved in the cycloaddition transition structure. At 198 K and in SO(2) solutions, the entropy cost (TDeltaS(++)) is overcompensated by the specific solvation by SO(2) in the transition structures of both the cheletropic and hetero-Diels-Alder reactions of (E)-1-methoxybutadiene with SO(2).
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Affiliation(s)
- Frédéric Monnat
- Section de Chimie de l'Université de Lausanne, CH-1015 Lausanne-Dorigny, Switzerland
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24
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Roversi E, Scopelliti R, Solari E, Estoppey R, Vogel P, Braña P, Menéndez B, Sordo JA. The hetero-Diels-Alder addition of sulfur dioxide to 1-fluorobuta-1,3-dienes: the sofa conformations preferred by 6-fluorosultines (6-fluoro-3,6-dihydro-1,2-oxathiin-2-oxides) enjoy enthalpic and conformational Anomeric effects. Chemistry 2002; 8:1336-55. [PMID: 11921217 DOI: 10.1002/1521-3765(20020315)8:6<1336::aid-chem1336>3.0.co;2-r] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
The reactivity of (E)- and (Z)-1-fluorobuta-1,3-diene ((E)- and (Z)-11), 2-fluorobutadiene (12), (E)- and (Z)-1-(fluoromethylidene)-2-methylidenecyclohexane ((E)- and (Z)-13) toward SO(2) has been explored and compared with that of (Z)- and (E)-1-(fluoromethylidene)-2-methylidene-3,4-dihydronaphthalene ((Z)-8 and (E)-8). In agreement with quantum calculations, 12 is unreactive toward SO(2) (no cycloaddition, only polymerization), whereas (E)-1-fluoro-1,3-dienes react more rapidly than their (Z)-isomers to give the corresponding 6-fluorosultines following the endo (Alder rule) mode of hetero-Diels-Alder addition. No sulfolene has been observed following the cheletropic mode of addition with the fluorodienes, in contrast to other substituted dienes. In agreement with the calculations, cis-2-fluoro-3,4-oxathiabenzobicyclo[4.4.0]dec-1(6),9-diene-4-oxide (cis-9, the sultine obtained by SO(2) addition to (Z)-8 under conditions of kinetic control) adopts a sofa conformation with the oxygen atom of the ring lying in the average plane of the four carbon atoms of its sultine moiety when it is in the crystalline state at -100 degrees C. A similar sofa conformation was found for its trans-isomer, trans-9, obtained by isomerization of cis-9 or by hetero-Diels-Alder addition of SO(2) to (E)-8. Experiments (equilibrium constant for hetero-Diels-Alder additions, bond lengths, and bond angles in crystalline fluorosultines cis-9 and trans-9) and high-level quantum calculations on cis- and trans-6-fluoro-3,6-dihydro-1,2-oxathiin-2-oxide (cis- and trans-20) confirm the existence of a stabilizing, enthalpic, anomeric (gem-disubstitution by sulfinyloxy and fluoro groups) effect, which is interpreted in terms of (lone pair) n(O1)-->sigma*(C-F) hyperconjugative interactions. This effect is strongest in the sofa conformers with a gauche arrangement of the sigma(O1,S2) and sigma(C6,F) bonds. The calculations suggest also that n(O1)-->sigma*(S2,O2'), pi*(S=O), and n(S2)-->sigma*(O1,C6) interactions intervene and affect the relative stability of the conformers (sofa, boat, pseudo-chair) found for 6-fluorosultines cis- and trans-20.
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Affiliation(s)
- Elena Roversi
- Section de Chimie de l'Université, BCH, 1015 Lausanne-Dorigny, Switzerland
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Narkevitch V, Megevand S, Schenk K, Vogel P. Development of a new carbon-carbon bond forming reaction. new organic chemistry of sulfur dioxide. Asymmetric four-component synthesis of polyfunctional sulfones. J Org Chem 2001; 66:5080-93. [PMID: 11463260 DOI: 10.1021/jo0101712] [Citation(s) in RCA: 36] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
At low temperature 1-alkoxy-1,3-dienes add to sulfur dioxide activated by a Lewis or Brønstedt acid and generate zwitterionic intermediates that can be quenched by enoxysilanes. The resulting beta,gamma-unsaturated silyl sulfinates can be desilylated and reacted with methyl iodide to provide polyfunctional sulfones. Exploratory studies of this four-component synthesis of sulfones are reported. Enantiomerically pure derivatives containing up to three new stereogenic centers can be obtained using enantiomerically pure (E,E)-1-alkoxy-2-methylpenta-1,3-dienes derived from alpha-methyl benzyl alcohols, including the Greene's chiral auxiliary. The stereochemistry of the reactions is consistent with a mechanism involving the suprafacial hetero-Diels-Alder addition of sulfur dioxide to the 1-alkoxy-1,3-dienes that are rapidly ionized into zwitterionic intermediates.
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Affiliation(s)
- V Narkevitch
- Section de Chimie, Université de Lausanne, BCH, CH-1015 Lausanne-Dorigny, Switzerland
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Megevand S, Moore J, Schenk K, Vogel P. Four component synthesis of (Z)-4-alkoxy-1,3-dimethylalk-2-enyl methyl sulfones: on the intermediacy of sultines (3,6-dihydro-1,2-oxathiin-2-oxides) arising from suprafacial hetero-Diels–Alder additions of sulfur dioxide. Tetrahedron Lett 2001. [DOI: 10.1016/s0040-4039(00)02102-x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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