Oxidative heck - University of Wisconsin
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Transcript Oxidative heck - University of Wisconsin
CATALYTIC FUJIWARA-MORITANI
REACTION. CHALLENGES IN C-H
ACTIVATION AND CATALYST
OXIDATION.
Laura Ruiz Espelt
Yoon Group
University of Wisconsin-Madison
Literature Seminar
April 7, 2011
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• Discovered in 1968 independently by Mizoroki and Heck
• Attractive transformation for C-C bond formation
• Richard F. Heck obtained the Nobel Prize on 2010
• Intensively developed from synthetic and mechanistic point of view
Oestrich, M. The Mizoroki-Heck Reaction; John Wiley & Sons, 2009
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Garg, N.K.; Caspi, D.D.; Stoltz, B.M. Synlett 2006, 18, 3081
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Garg, N.K.; Caspi, D.D.; Stoltz, B.M. Synlett 2006, 18, 3081
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Garg, N.K.; Caspi, D.D.; Stoltz, B.M. Synlett 2006, 18, 3081
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Moritani, I.; Fujiwara, Y. Tetrahedron Lett. 1967, 12, 1119
Fujiwara, Y.; Moritani, I.; Matsuda, M.; Teranishi, S. Tetrahedron Lett. 1968, 5, 633
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Fujiwara, Y.;Asano, R.; Moritani, I.; Teranishi, S. J. Org. Chem. 1976, 41, 1681
Fujiwara, Y.;Asano, R.; Moritani, I.; Teranishi, S.
J. Org. Chem. 1976, 41, 1681
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Fujiwara, Y.; Moritani, I.; Danno, S.; Asano, R.; Teranishi, S. J. Am. Chem. Soc. 1969, 7166
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Oestrich, M. The Mizoroki-Heck Reaction; John Wiley & Sons, 2009, p. 14
Fujiwara, Y.; Moritani, I.; Danno, S.; Asano, R.; Teranishi, S.
J. Am. Chem. Soc. 1969, 7166
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Challenge 1: C-H Activation
Challenge 2: Pd(0) Oxidation
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1.
2.
C-H bonds easier to activate
Complete ortho regioselectivity for symmetrical substrates
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Satoh and Miura (2009)
Umeda N.; Hirano, K.; Satoh, T.; Miura, M. J. Org. Chem. 2009, 74, 7094
Shi (2007)
Cai, G.; Fu, Y.; Li, Y.; Wan, X.; Shi, Z. J. Am. Chem. Soc. 2007, 129, 7666
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-
Entry into phthalide core
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Reaction catalyzed by [Pd] cyclizes after first vinylation
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Reaction catalyzed by [Rh] suffers a second vinylation before the cyclization step
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No mechanistic insight
Ueura, K.; Satho, T.; Miura, M. Org. Lett. 2007, 9, 1407-1409
Miura, M.; Tsuda, T.; Satoh, T.; Pivsa-Art, S.; Nomura, M. J. Org. Chem. 1998, 63, 5211-5215
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Ryabov, A.D.; Sakodinskaya, I.K.; Yatsimirsky, A.K. J. Chem. Soc. Dalton Trans. 1985, 2629
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BP86 / 6-31G**
Davies, D.; Donald, S.M.A.; Macgregor, S.T. J. Am. Chem. Soc. 2005, 127, 13754
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Short distance between Pd and H
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Elongated C-H bond
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No charge change in aromatic ring
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Maehara, A.; Tsurugi, H.; Satoh, T.; Miura, M. Org. Lett. 2008, 10, 1159
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Ferreira, E.; Stoltz, B.M. J. Am. Chem. Soc. 2003, 125, 9578
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Zhang, Y.; Shi, B.; Yu, J.Q. J. Am. Chem. Soc. 2009, 131, 5072
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0.05 Å
longer than
Pd(Pyr)2(OAc)2
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Origin of meta selectivity still unclear
Zhang, Y.; Shi, B.; Yu, J.Q. J. Am. Chem. Soc. 2009, 131, 5072
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Wang, D.; Engle, K.; Shi, B.; Yu, J.Q. Science. 2010, 327, 315
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Engle, K.M.; Wang, D.; Yu, J.Q. J. Am. Chem. Soc. 2010, 132, 14137
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Engle, K.M.; Wang, D.; Yu, J.Q. J. Am. Chem. Soc. 2010, 132, 14137
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Engle, K.M.; Wang, D.; Yu, J.Q. J. Am. Chem. Soc. 2010, 132, 14137
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Many improvements achieved since Fujiwara’s initial observations
Two main tactics used to achieve regioselectivity:
1. Directing groups- site selective palladation
2. Ligands- not fully understood
More “synthetically appealing” directing groups design: traceless directing groups
Future of ligands to direct reactivity and selectivity
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Fujiwara (1968)
Fujiwara, Y.; Moritani, I.; Matsuda, M.; Teranishi, S. Tetrahedron Lett. 1968, 35, 3863
Itahara (1983)
Itahara, T.; Ikeda, M.; Sakakibara, T. J. Chem. Soc. Perkin Trans 1. 1983, 1361
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“Green Oxidants”: O2
Pros: - Environmentally friendly
- Lower cost
- Increase in atom efficiency
- Facilitate product isolation
Stahl, S. Angew. Chem. Int. Ed. 2004, 43, 3400
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“Green Oxidants”: O2
Cons: - O2 requires rigorous safety handling
- Slow electron transfer compared to
decomposition of the reduced metal
Solution: - Use of ligands to stabilize Pd0 so that is stable under oxidative conditions
- Use an electron-transfer mediator to carry the electrons from Pd0 to terminal
“green oxidant’
Piera, J.; Backvall, J.E. Angew. Chem. Int. Ed. 2008, 47, 350610
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Yokota, T.; Tani, M.; Sakaguchi, S. Ishii, Y. J. Am. Chem. Soc. 2003, 125, 1476
Want, J.; Yang, C.; Liu, L.; Guo, Q. Tet. Letters. 2007, 48, 5449
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Shue, R.S. Chem. Commun. 1971, 1510
Dams, M.; De Vos, D.E.; Celen, S.; Jacobs, P.A. Angew. Chem. Int. Ed. 2003, 42, 3512
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Ferreira, E.; Stoltz, B.M. J. Am. Chem. Soc. 2003, 125, 9578
2 equiv
Engle, K.M.; Wang, D.; Yu, J.Q. J. Am. Chem. Soc. 2010, 132, 14137
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Challenge: Use a Directing Group that
acts also as the Oxidant:
OXIDIZING DIRECTING GROUPS
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Rakshit, S.; Grohmann, C.; Besset, T.; Glorius, F. J. Am. Chem. Soc. 2011, 133, 2350
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Wu,J.; Cui, X.; Chen, L.; Jiang, G.; Wu, Y. J. Am. Chem. Soc. 2009, 131, 13888
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Rakshit, S.; Grohmann, C.; Besset, T.; Glorius, F. J. Am. Chem. Soc. 2011, 133, 2350
Wu,J.; Cui, X.; Chen, L.; Jiang, G.; Wu, Y. J. Am. Chem. Soc. 2009, 131, 13888
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Cho, S.H.; Hwang, S.J.; Chang, S.
J. Am. Chem. Soc. 2008, 130, 9254
Wu,J.; Cui, X.; Chen, L.; Jiang, G.; Wu, Y.
J. Am. Chem. Soc. 2009, 131, 13888
Pauterau, F.W.; Besset, T.; Glorius, F.
Angew. Chem. Int. Ed. 2011, 50, 1064
Rakshit, S.; Grohmann, C.; Besset, T.; Glorius, F.
. Am. Chem. Soc. 2011, 133, 2350-2353
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Two main tactics used to achieve
regioselectivity:
1.Directing groups
2. Ligands
Oxidation on catalyst achieved by:
1. Stoichiometric oxidants such as Cu(OAc)2
or AgOAc
2. Oxygen in the presence of electrontransfer-mediators such as Cu(OAc)2 or
polyoxometallate acids
3. Oxygen as sole oxidant in the presence
of ligands to stabilize the metal
Oxidizing directing group opens new avenues for this chemistry
Advantages/ disadvantages have to be evaluated individually
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Thank you!
Professor Tehshik Yoon
Kat Myhre
The Yoon Group
Practice Talk Attendees:
Travis Blum
Jamie Chen
Megan Cismesia
Juana Du
Olga Dykhno
Elliot Farney
Anna Hurtley
Shishi Lin
Zic Lu
Jon Parrish
Derek Salter
Liz Tyson
Kevin Williamson
Adam Weinstein