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Organohypervalent Iodine as Mild and Selective Reagents for Multiple Oxidation Processes. Benoît Moreau. Literature Meeting June 6 th , 2005. Iodine. I: [Kr] 4d 10 5s 2 p 5. Oxidation states: 7, 5, 3, 1, and -1. Geometry: Orthorhombic. Group 17 (Halogens).
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Organohypervalent Iodine as Mild and Selective Reagents for Multiple Oxidation Processes Benoît Moreau Literature Meeting June 6th, 2005
Iodine I: [Kr] 4d10 5s2 p5 Oxidation states: 7, 5, 3, 1, and -1 Geometry: Orthorhombic Group 17 (Halogens) Discovered in 1811, by Bernard Courtois, France He isolated iodine from treating seaweed ash with sulphuric acid (H2SO4) while recovering sodium and potassium compounds. From the Greek word "iodes" meaning "violet" Iodine exhibits some metallic-like properties. www.webelements.com
Iodine: Oxidation States Commonly used for… - Various purposes! - mild alcohol oxidation - 1,2-diol cleavage
Hypervalent Iodine: Timeline 1886 Ph-ICl2 prepared by Willgerodt 1914 Nearly 500 compounds known. 1957 First iodonium ylide prepared. Since 1990, ‘‘rediscovery’’ of hypervalent organoiodinecompounds - Applied to total synthesis of a large number of natural products - Many reviews lately - Use extended to various processes Why? - similar reactivity to Hg(II), Tl(III), andPb(IV) - similarities (reductive elimination,ligand exchange, etc.) with organic transitionmetal complexes - PhI(OAc)2 is commercially available Willgerodt, C. J. Prakt. Chem. 1886, 33, 154. Willgerodt, C. Die Organischen Verbindungen mit MehrwertigenJod; Ferdinand Enke Verlag: Stuttgart, 1914. V. V. Zhdankin, P. J. Stang, Chem. Rev. 2002, 102, 2523 – 2584.
Preparation of PhI=O and PhI(OAc)2 Efficient oxidant Almost insoluble in most solvents (polymeric structure) Commercially available ca. 500$/kg Easily recrystallized and stored for extended periods of time without significant decomposition
Hypervalent Iodine 1- Various oxidation processes Reaction of Ylides Oxidation of CH-OH bond Functionnalization a to carbonyls 2- Radical generation Suarez’s contribution Application in total synthesis 3- Phenolic oxidation Seminal work Application to natural product synthesis Wipf’s contribution Porco’s contribution
Hypervalent Iodine 1- Various oxidation processes Reaction of Ylides Oxidation of CH-OH bond Functionnalization a to carbonyls 2- Radical generation Suarez’s contribution Application in total synthesis 3- Phenolic oxidation Seminal work Application to natural product synthesis Wipf’s contribution Porco’s contribution
Iodonium Ylides as Precursors for Epoxidation, Aziridination and Cyclopropanation Daly, A. M. et al, Org. Lett. 2001, 3, 663. Dauban, P. et al, J. Am. Chem. Soc. 2001, 123, 7707-7708 Koskinen, A. M. P.et al,Acta Chem. Scand.1996, 50, 323-327. Muller, P. Acc. Chem. Res. 2004, 37, 243-251.
Amination through C-H activation Intermolecular Kohmura, Y.; Katsuki, T. Tetrahedron Lett. 2001, 42, 3339. Intramolecular Du Bois, J. et al, J. Am. Chem. Soc. 2001, 123, 6935 – 6936.
Non-catalyzed C-H activation of Aromatics Misu, Y. et al, Org. Biomol. Chem. 2003, 1, 1342 – 1346. Kita, Y. et al, Tetrahedron Lett. 2004, 45, 2293 – 2295. Kikugawa, Y.et al, J. Org. Chem. 2003, 68, 6739 – 6744.
Reaction of Iodonium Ylides: Hoffmann Rearrangement Zhang, L.-H.; Kauffman, G. S.; Pesti, J. A.; Yin, J. J. Org. Chem.1997, 62, 6918.
Alcohol Oxidation by PhI=O Kita, Y. et al, Synlett 2003, 723
Alcohol Oxidation by PhI=O: Mechanism Kita, Y. et al, Synlett 2003, 723
Alcohol Oxidation with PhI(OAc)2 Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977.
Alcohol Oxidation with PhI(OAc)2 - Primary alcohol is oxidated selectively over secondary (competition experiment) - Reaction works best when performed in polar solvents - This selective oxidation was used twice by Paterson during Discodermolide synthesis Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977. Paterson I. et al, Org. Lett. 2003, 5,35-38.
Alcohol Oxidation with TEMPO/PhI(OAc)2: Mechanism Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977.
Halogenation a to Carbonyls Motherwell, W. B. et al, Tetrahedron Lett 2000, 41, 4463-4466. tolI(F)2 synthesis: Hara, S. et al, Synthesis 2002, 13, 1802–1803.
Halogenation a to Carbonyls: Mechanism Motherwell, W. B. et al, Tetrahedron Lett 2000, 41, 4463-4466.
Halogenation a to Carbonyls: Asymmetric Induction Challenge: suppress uncatalyzed background reaction betweenthehypervalent iodine reagent and thesubstrate. Togni, A. et al, Helv. Chim. Acta 2004, 87,605 – 610.
Functionnalization a to Carbonyls: Hydroxylation I(III) source preparation: Moriarty, R. M.; Condeiu, C.; Tao, A.; Prakash, O. TetrahedronLett. 1997, 38, 2401.
Olefin Functionnalization Mechanism: Hara, S.et al,Synlett 1998, 495.
Styrene Rearrangement Miki, Y.; Fujita, R.; Matsushita, K.-I. J. Chem. Soc., PerkinTrans. 1 1998, 2533.
Olefin functionnalization: Styrene Rearrangement Over 25 examples, 70-92% Mechanism: M.W. Justik, G. F. Koser, Tetrahedron Lett. 2004, 45, 6159 –6163.
Hypervalent Iodine 1- Various oxidation processes Reaction of Ylides Oxidation of CH-OH bond Functionnalization a to carbonyls 2- Radical Generation Suarez’s contribution Application in total synthesis 3- Phenolic oxidation Seminal work Application to natural product synthesis Wipf’s contribution Porco’s contribution
Hemiacetal Oxidation with PhI(OAc)2 Posner, G. H. et al, Tetrahedron Lett. 2003, 44, 5407-5409. N. G. Ramesh, A. Hassner, Synlett2004, 975 – 978.
Hemiacetal Oxidation with PhI(OAc)2: Rationale for Selectivity ‘‘The high stereoselectivityin favor of 10 may be due to the presence of the vicinal tert-butoxycarboxymethyl side chain.’’ N. G. Ramesh, A. Hassner, Synlett2004, 975 – 978.
Formation of Alkoxy Radicals Mechanism? Suarez, E.et al,J. Org. Chem.1998, 63, 2099.
Formation of Alkoxy Radicals Mechanism: Suarez, E.et al,J. Org. Chem.1998, 63, 2099.
Formation of Alkoxy Radicals Suarez, E.et al,J. Org. Chem. 2001, 66, 1861.
Formation of Radicals: Further Extension of Methodology Suarez, E. et al, Tetrahedron: Asymmetry2000, 11, 3879.
Formation of Radicals: Further Extension of Methodology Suarez, E. et al, Tetrahedron Letters2000, 41, 7869–7873.
Alkoxy Radical Generation: Application to Total Synthesis of Avermectin Danishefsky, S. J. et al, J. Am. Chem. Soc. 1989, 111, 2961-2980.
Alkoxy Radical Generation: Application to Total Synthesis of Dumsin Dumsin Paquette, L. A.; Hong, F.-T. J. Org. Chem. 2003, 68, 6905.
Hypervalent Iodine 1- Various oxidation processes Reaction of Ylides Oxidation of CH-OH bond Functionnalization a to carbonyls 2- Radical Generation Suarez’s contribution Application in total synthesis 3- Phenolic oxidation Seminal work Application to natural product synthesis Wipf’s contribution Porco’s contribution
Phenol oxidation General Scheme Nucleophiles: water, alcohols, amines, acids
Phenol oxidation: Seminal Work Kita, Y. et al, J. Org. Chem. 1987,52, 3927-3930 Pelter, A.; Elgendy, S. J. Chem. Soc., Perkin Trans. 1, 1993, 1891.
Phenol oxidation: Extension of the Methodology Mitchell, A. S.; Russell, R. A. Tetrahedron Lett. 1993, 34,545. Barret, R.; Daudon, M. Tetrahedron Lett. 1991, 32, 2133.
Phenol oxidation: Extension of the Methodology Abrams, S. R. et al, Phytochemistry 1994, 37, 289. Breuning, M.; Corey, E. J. Org. Lett. 2001, 3, 1559.
Phenol oxidation: Application to Miroestrol Synthesis Miroestrol Corey, E. J.; Wu, L. I. J. Am. Chem. Soc. 1993, 115, 9327.
Phenol Oxidation: Application to Natural Product Synthesis Kita, Y. et al, J. Am. Chem. Soc. 2003, 125, 11235 – 11240.
Asymmetric Synthesis of p-Quinols Pettus, T. R. R. et al, Org. Lett. 2004, 6,1535-1538.
Asymmetric Synthesis of p-Quinols: Proposed Model Pettus, T. R. R. et al, Org. Lett. 2004, 6,1535-1538.
Tuberostemonine: Natural Product of Interest Isolated in 1934 and in 1936, fromStemona tuberosa and Stemona sessifolia roots. Extracts from these plantshave been used for centuries in easterncultures for the treatmentof various respiratory problems, such aspertussis, bronchitis,and tuberculosis Suzuki, K. J. Pharm. Soc. Jpn. 1934, 54, 573. Kondo, H.; Suzuki, K.; Satomi, M. J. Pharm. Soc. Jpn.1939, 59, 443. Schild, H. Ber. Dtsch. Chem. Ges. 1936, 69B, 74.
Stemona Alkaloids Family Kondo, H.; Suzuki, K.; Satomi, M. J. Pharm. Soc. Jpn.1939, 59, 443.
Wipf’s Contribution to Stemona Alkaloids Synthesis Key Reaction: - This motif was used as building block to access various natural products Wipf, P.; Kim, Y. Tetrahedron Lett. 1992, 33, 5477. Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
Oxidative Spirocyclization ofl-Tyrosine Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
Total Synthesis of Tuberostemonine Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
Synthesis of Tuberostemonine: Metathesis and Lactone Introduction Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.