Classification multiclasses Maxime Benoît-Gagné. Introduction.
Benoît Moreau
description
Transcript of Benoît Moreau
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Benoît Moreau
Organohypervalent Iodine as Mild and Selective Reagents for Multiple Oxidation Processes
Literature MeetingJune 6th, 2005
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www.webelements.com
Iodine
I: [Kr] 4d10 5s2 p5
Oxidation states: 7, 5, 3, 1, and -1Geometry: Orthorhombic
Discovered in 1811, by Bernard Courtois, France
From the Greek word "iodes" meaning "violet"
He isolated iodine from treating seaweed ash with sulphuric acid (H2SO4)while recovering sodium and potassium compounds.
Iodine exhibits some metallic-like properties.
Group 17 (Halogens)
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Iodine: Oxidation States
I(+5)
I(+7)
IO
O
AcOOAc
OAcI
O
O
O O
Dess-Martin periodinane IBX
I(+3)
NaIO4
IOAc
OAc
IO
- 1,2-diol cleavage
- mild alcohol oxidation
- Various purposes!
Commonly used for…
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Hypervalent Iodine: Timeline
1886 Ph-ICl2 prepared by Willgerodt
Since 1990, ‘‘rediscovery’’ of hypervalent organoiodine compounds
- 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), and Pb(IV)- similarities (reductive elimination, ligand exchange, etc.) with organic transition metal complexes- PhI(OAc)2 is commercially available
1914 Nearly 500 compounds known.
Willgerodt, C. J. Prakt. Chem. 1886, 33, 154.Willgerodt, C. Die Organischen Verbindungen mit Mehrwertigen Jod;
Ferdinand Enke Verlag: Stuttgart, 1914.V. V. Zhdankin, P. J. Stang, Chem. Rev. 2002, 102, 2523 – 2584.
1957 First iodonium ylide prepared.
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Preparation of PhI=O and PhI(OAc)2
I
IO
IOAc
OAc
OH , H2O
AcOH, H2O2
Ac2O, H2O2
H2O
H2O
Efficient oxidant
Almost insoluble in most solvents(polymeric structure)
Commercially available ca. 500$/kg
Easily recrystallized and stored forextended periods of time without significant decomposition
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Hypervalent Iodine
Reaction of Ylides Oxidation of CH-OH bondFunctionnalization to carbonyls
1- Various oxidation processes
3- Phenolic oxidation
Seminal workApplication to natural product synthesisWipf’s contributionPorco’s contribution
2- Radical generation
Suarez’s contributionApplication in total synthesis
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Reaction of Ylides Oxidation of CH-OH bondFunctionnalization to carbonyls
Hypervalent Iodine
1- Various oxidation processes
3- Phenolic oxidation
Seminal workApplication to natural product synthesisWipf’s contributionPorco’s contribution
2- Radical generation
Suarez’s contributionApplication in total synthesis
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Iodonium Ylides: Definition
C
I
R R
N
I
RO
I
Ph
Ph
Ph
C
I
R R
N
I
R
Ph
Ph
O
IPh
CR R
H H
NH2R
- H2O
- H2O
Also: P, S, Se iodonium ylides
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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.
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Amination through C-H activation
Du Bois, J. et al, J. Am. Chem. Soc. 2001, 123, 6935 – 6936.
Kohmura, Y.; Katsuki, T. Tetrahedron Lett. 2001, 42, 3339.
Intermolecular
Intramolecular
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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.
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Reaction of Iodonium Ylides:Hoffmann Rearrangement
Zhang, L.-H.; Kauffman, G. S.; Pesti, J. A.; Yin, J. J. Org. Chem. 1997, 62, 6918.
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Alcohol Oxidation by PhI=O
Kita, Y. et al, Synlett 2003, 723
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Alcohol Oxidation by PhI=O: Mechanism
Kita, Y. et al, Synlett 2003, 723
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Alcohol Oxidation with PhI(OAc)2
Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977.
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- 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
Paterson I. et al, Org. Lett. 2003, 5, 35-38.
Alcohol Oxidation with PhI(OAc)2
Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977.
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Alcohol Oxidation with TEMPO/PhI(OAc)2: Mechanism
Margarita, R. et al, J. Org. Chem. 1997, 62, 6974 – 6977.
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tolI(F)2 synthesis: Hara, S. et al, Synthesis 2002, 13, 1802–1803.
Halogenation to Carbonyls
Motherwell, W. B. et al, Tetrahedron Lett 2000, 41, 4463-4466.
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Halogenation to Carbonyls: Mechanism
Motherwell, W. B. et al, Tetrahedron Lett 2000, 41, 4463-4466.
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Togni, A. et al, Helv. Chim. Acta 2004, 87, 605 – 610.
Halogenation to Carbonyls: Asymmetric Induction
Challenge: suppress uncatalyzed background reaction between the hypervalent iodine reagent and the substrate.
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Functionnalization to Carbonyls: Hydroxylation
Moriarty, R. M.; Condeiu, C.; Tao, A.; Prakash, O. Tetrahedron Lett. 1997, 38, 2401.
I(III) source preparation:
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Olefin Functionnalization
Mechanism:
Hara, S. et al, Synlett 1998, 495.
R R
F F
IF2
53-70%
R = C10H21, HOC9H18, AcOC9H18, AcOC4H8, MeO2CC8H18, ClC9H18, etc.
Et3N.5HF, CH2Cl2, -78 to 0 oC, 2h
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Styrene Rearrangement
Miki, Y.; Fujita, R.; Matsushita, K.-I. J. Chem. Soc., Perkin Trans. 1 1998, 2533.
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Olefin functionnalization: Styrene Rearrangement
M.W. Justik, G. F. Koser, Tetrahedron Lett. 2004, 45, 6159 –6163.
Over 25 examples, 70-92%
Mechanism:
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Reaction of Ylides Oxidation of CH-OH bondFunctionnalization to carbonyls
2- Radical Generation
Suarez’s contributionApplication in total synthesis
Hypervalent Iodine
1- Various oxidation processes
3- Phenolic oxidation
Seminal workApplication to natural product synthesisWipf’s contributionPorco’s contribution
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Hemiacetal Oxidation with PhI(OAc)2
Posner, G. H. et al, Tetrahedron Lett. 2003, 44, 5407-5409.
N. G. Ramesh, A. Hassner, Synlett 2004, 975 – 978.
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Hemiacetal Oxidation with PhI(OAc)2: Rationale for Selectivity
‘‘The high stereoselectivity in favor of 10 may be due to the presence of the vicinaltert-butoxycarboxymethyl side chain.’’
N. G. Ramesh, A. Hassner, Synlett 2004, 975 – 978.
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Suarez, E. et al, J. Org. Chem. 1998, 63, 2099.
Formation of Alkoxy Radicals
O
ORRO
HO2C OH O
ORHOCO
O ORPhI(OAc)2/I2
43-70%
Mechanism?
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Suarez, E. et al, J. Org. Chem. 1998, 63, 2099.
Formation of Alkoxy Radicals
O
ORRO
HO2C OH O
ORHOCO
O ORPhI(OAc)2/I2
43-70%
Mechanism:
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Formation of Alkoxy Radicals
Suarez, E. et al, J. Org. Chem. 2001, 66, 1861.
O
ORRO
OH N
ORHOCO
ORPhI(OAc)2/I2
RHN R
R= Boc or P(O)Ph2
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Formation of Radicals: Further Extension of Methodology
O R O RPhI(OAc)2 or PhI=ORN
I2O O
NR
O O
Suarez, E. et al, Tetrahedron: Asymmetry 2000, 11, 3879.
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O R O RPhI(OAc)2 or PhI=OHO
I2O O
O
O O
Formation of Radicals: Further Extension of Methodology
Suarez, E. et al, Tetrahedron Letters 2000, 41, 7869–7873.
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Formation of Alkoxy Radicals: Mechanism
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Alkoxy Radical Generation: Application to Total Synthesis of Avermectin
OOH Me
MeH
OP
RMe
OO Me
MeH
OP
RMe
H
OO
Me
MeH
O
MeH
O
O
OH
HMe
OMe
Me
OMeOO
OMeMe
OHOOMe
Me
Avermectin A1a
HgO
Danishefsky, S. J. et al, J. Am. Chem. Soc. 1989, 111, 2961-2980.
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Paquette, L. A.; Hong, F.-T. J. Org. Chem. 2003, 68, 6905.
Dumsin
Alkoxy Radical Generation: Application to Total Synthesis of Dumsin
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Reaction of Ylides Oxidation of CH-OH bondFunctionnalization to carbonyls
3- Phenolic oxidation
Seminal workApplication to natural product synthesisWipf’s contributionPorco’s contribution
2- Radical Generation
Suarez’s contributionApplication in total synthesis
Hypervalent Iodine
1- Various oxidation processes
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Phenol oxidation
OH O
Nu
PhI(OAc)2
OI
Ph
OAc
NuH
- AcOH - AcOH- Ph-I
R R R
General Scheme
Nucleophiles: water, alcohols, amines, acids
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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.
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Phenol oxidation: Extension of the Methodology
Barret, R.; Daudon, M. Tetrahedron Lett. 1991, 32, 2133.
Mitchell, A. S.; Russell, R. A. Tetrahedron Lett. 1993, 34, 545.
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Phenol oxidation: Extension of the Methodology
Breuning, M.; Corey, E. J. Org. Lett. 2001, 3, 1559.
Abrams, S. R. et al, Phytochemistry 1994, 37, 289.
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O
OH
OH
HOHO
O
H
Corey, E. J.; Wu, L. I. J. Am. Chem. Soc. 1993, 115, 9327.
Phenol oxidation: Application to Miroestrol Synthesis
Miroestrol
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Phenol Oxidation: Application to Natural Product Synthesis
Kita, Y. et al, J. Am. Chem. Soc. 2003, 125, 11235 – 11240.
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Asymmetric Synthesis of p-Quinols
Pettus, T. R. R. et al, Org. Lett. 2004, 6, 1535-1538.
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Asymmetric Synthesis of p-Quinols: Proposed Model
Pettus, T. R. R. et al, Org. Lett. 2004, 6, 1535-1538.
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Extracts from these plants have been used for centuries in eastern cultures for the treatment of various respiratory problems, such as pertussis, bronchitis, and tuberculosis
Isolated in 1934 and in 1936, from Stemona tuberosa and Stemona sessifolia roots.
Tuberostemonine: Natural Product of Interest
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.
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Stemona Alkaloids Family
N
OHOH
O
HO O
H
N
O
O
O
O
HO
HO
Oxotuberostemonine Tuberostemonone
N HO O
H
N HO O
H
OO H
Stemoninine
O
O H
HH
H
H
O
Parvistemonine
Kondo, H.; Suzuki, K.; Satomi, M. J. Pharm. Soc. Jpn.1939, 59, 443.
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Wipf’s Contribution to Stemona Alkaloids Synthesis
- This motif was used as building block to access various natural products
Key Reaction:
Wipf, P.; Kim, Y. Tetrahedron Lett. 1992, 33, 5477.Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
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Oxidative Spirocyclization of l-Tyrosine
Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
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Total Synthesis of Tuberostemonine
Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
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Synthesis of Tuberostemonine: Metathesis and Lactone Introduction
Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
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Total Synthesis of Tuberostemonine: End Game
Wipf, P.; Spencer, S. R. J. Am. Chem. Soc. 2005, 127, 225.
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Epoxyquinoids: Natural Products of Interest
- Isolated in 1996 from Pestalotiopsis spp., a fungal genus also producing Taxol. Fongus grows on Florida torreya tree.
-Inhibitor of the phosphorylation of the NF-kB inhibitory protein IkB. Potent antiangiogenic activity.
Lee, J. C.; Strobel, G. A.; Lobkovsky, E.; Clardy, J. J. Org. Chem. 1996, 61, 3232.
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Epoxiquinoids: Porco’s Contribution
OMe
OH
R
O
RMeO OMe
O
RMeO OMe
OPhI(OAc)2, MeOH Directed epoxidation
General Scheme
- This motif is a common building block to access various natural products
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Torreyanic Acid Synthesis
Li, C.; Lobkovsky, E.; Porco, J. A. Jr. J. Am. Chem. Soc. 2000, 122, 10484.
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Li, C.; Lobkovsky, E.; Porco, J. A. Jr. J. Am. Chem. Soc. 2000, 122, 10484.
Torreyanic Acid Synthesis
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Tandem Oxidation/Electrocyclization/Dimerization Process
Endo cyclization
This is also the proposed biosynthesis of Torreyanic Acid
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Asymmetric Syntheses of Torreyanic Acid
Li, C.; Johnson, R. P.; Porco, J. A. Jr. J. Am. Chem. Soc. 2003, 125, 5095.
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Asymmetric Syntheses of Torreyanic Acid and Ambuic Acid
Li, C.; Johnson, R. P.; Porco, J. A. Jr. J. Am. Chem. Soc. 2003, 125, 5095.
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Common Intermediate to Torreyanic Acid and Ambuic Acid
Li, C.; Johnson, R. P.; Porco, J. A. Jr. J. Am. Chem. Soc. 2003, 125, 5095.
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(-)-Jesterone Synthesis
MeO
O
HOO
Me
Me
MeO
OH
HOO
Me
Me
MeO
OH
HOO
Me
Me
a
b
Porco, J. A. Jr. et al, Org. Lett. 2001, 3, 1649.
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(-)-Cycloepoxydon Synthesis
Porco, J. A. Jr. Et al, J. Am. Chem. Soc. 2001, 123, 11308.
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(+)-Panepophenanthrin Synthesis
10% HF, CH3CN/
CH2Cl2, RT, 1 h.
40%
Lei, X.; Johnson, R. P.; Porco, J. A. Jr. Angew. Chem. Int. Ed. 2003, 42, 3913
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Takeuchi, T. et al, J. Nat. Prod. 2002, 65, 1491.Xiang Wang and John A. Porco, Jr., Angew. Chem. Int. Ed. 2005, 44, 3067 –3071.
Phenol oxidation: Porco’s Synthesis of the Tetrapetalone Core
Isolated from the mushroom strain Panus rudis Fr. IFO8994.
First naturally occurring inhibitor of ubiquitin-activating enzyme
(abnormal ubiquitination-mediated protein degradation may be associated with human cancers, inflammation, and neurodegenerative disease.)
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[O]
Phenol oxidation: Strategy for Access to the Tetrapetalone Core
Xiang Wang and John A. Porco, Jr., Angew. Chem. Int. Ed. 2005, 44, 3067 –3071.
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Tetracyclic Core of the Tetrapetalones
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Xiang Wang and John A. Porco, Jr., Angew. Chem. Int. Ed. 2005, 44, 3067 –3071.
Phenol Oxidation: Transannular [4+3] Cyclization
42% yield over 2 steps
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Tetracyclic Core of the Tetrapetalones
Xiang Wang and John A. Porco, Jr., Angew. Chem. Int. Ed. 2005, 44, 3067 –3071.
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Hypervalent Iodine: Summary
- Cyclopropanation, Aziridination, Epoxidation- Hoffmann Rearrangement - C-H insertion- Alcohol Oxidation - Functionnalization to carbonyls
1- Various oxidation processes
2- Radical generation
OH O
Nu
PhI(OAc)2
OI
Ph
OAc
NuH
- AcOH - AcOH- Ph-I
R R R
3- Phenolic oxidation