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Rhodium Catalyzed Alkene and Alkyne Hydroacylation. Wu Hua 2011-4-23. Content. Intramolecular Alkene Hydroacylation. Intermolecular Alkene Hydroacylation. Intramolecular Alkyne Hydroacylation. Intermolecular Alkyne Hydroacylation. First reported:.

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Wu Hua 2011-4-23

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Wu hua 2011 4 23

Rhodium Catalyzed Alkene and

Alkyne Hydroacylation

Wu Hua

2011-4-23


Wu hua 2011 4 23

Content

Intramolecular Alkene Hydroacylation

Intermolecular Alkene Hydroacylation

Intramolecular Alkyne Hydroacylation

Intermolecular Alkyne Hydroacylation


Wu hua 2011 4 23

First reported:

The reaction was discovered by K. Sakai in 1972 as part in a synthetic route to certain prostanoids

Proposed mechanism:

Sakai, K.; Ide, J.; Oda, O.; Nakamura, N. Tetrahedron Lett. 1972,1287.


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Milstein, D. J. Chem. Soc., Chem. Commun. 1982, 1357.

Lochow, C. F.; Miller, R. G. J. Am. Chem. Soc. 1976, 98, 1281.

Larock, R. C.; Oertle, K.; Potter, G. F. J. Am. Chem. Soc. 1980, 102, 190.


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Pluth, J. J. J. Am. Chem.Soc. 1977, 99, 8055.

Inactive [Rh(diphos)(CO)2]+.

Inactive [Rh(diphos)(CHCN)2]+.

Fairlie, D. P.; Bosnich, B. Organometallics 1988, 7, 936.


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Eilbracht, P.; Gersmeir, A.; Lennartz, D.; Huber, T. Synthesis 1995, 330


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Larger Ring Systems

a. Ring closure of these larger rings is generally slower than for five-ring formation

b. Decarbonylation can become problematic.

c. If a five-membered closure is possible, then this pathway will usually be followed.


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The authors reasoned that cyclopentanone formation is disfavored due to the ring strain that would be present in the resulting 5,5,5-tricyclic product.

Gable, K.; Benz, G. A. Tetrahedron Lett. 1991, 32, 3473.


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Sato, Y.; Oonishi, T.; Mori, M. Angew. Chem., Int. Ed. 2002, 41, 1218.

Oonishi, Y.; Mori, M.; Sato, Y. Synthesis 2007, 2323.


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Shair, M. D. J. Am. Chem. Soc. 2000, 122, 12610.


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The experiments led to two D-containing products in a ratio that exactly matched the E/Z ratio of the

substrates. The authors proposed that the E isomer generated the expected cyclooctenone directly, via the mechanism. However, to account for the unexpected scrambling of the D-label, they proposed

isomerization of the Z alkene via five-membered rhodacycles leading to intermediate, featuring an E-configured alkene.


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Stereoselective Reactions

Sakai, K. Tetrahedron Lett. 1984, 25, 961.


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Enantioselective Systems

James, B. R.; Young, C. G. J. Chem. Soc., Chem. Commun. 1983, 1215.

Sakai, K. Tetrahedron Lett. 1989, 30, 6349.


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Bosnich, B. J. Am. Chem. Soc. 1994, 116, 1821.


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Intermolecular Alkene Hydroacylation

Their success was attributed to intramolecular coordination of the alkene to aid in catalyst stabilization. The use of heteroatom chelation has emerged as a successful strategy for intermolecular hydroacylation and a number of systems have been reported.

Miller, R. G. J. Organomet. Chem. 1980, 192, 257.


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Suggs first isolated acyl rhodium(III) complexfrom the reaction of quinoline-8-carboxaldehyde and Wilkinson’s complex, and found that after treatment with AgBF4 and octene, the hydroacylation adduct could be isolated.

Suggs, J. W. J. Am. Chem. Soc. 1978, 100, 640.


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Lee, H.; Jun, C.-H. Bull. Korean Chem. Soc. 1995, 16, 66.

Suggs, J. W. J. Am. Chem. Soc. 1979, 101, 489.


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Jun, C.-H.; Hong, J.-B. Angew. Chem., Int. Ed. 2000, 39, 3070.


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Jun, C.-H. J. Org. Chem. 2002, 67, 3945.


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The rhodium complex first catalyzes the oxidation of the alcohol to the aldehyde, using an equivalent of alkene as the oxidant, before promoting the hydroacylation reaction as described previously.

Jun, C.-H.; Na, S.-J. Angew. Chem., Int. Ed. 1998, 37, 145.


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Nomura, M. Bull. Chem. Soc. Jpn. 1999, 72, 303.


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Salicylaldehydes in combination with diene substrates

Suemune, H. Org. Lett. 2003, 5, 1365.


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Willis, M. C. Angew. Chem., Int. Ed. 2004, 43, 340.


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Tanaka, K.; Hagiwara, Y.; Hirano, M. Org. Lett. 2007, 9, 1215.


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Roy, A. H.; Lenges, C. P.; Brookhart, M. J. Am. Chem. Soc. 2007, 129, 2082.


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Intramolecular Alkyne Hydroacylation

Perhaps due to the desire to generate organic molecules containing stereogenic centers, the study of alkynes in hydroacylation reactions has received significantly less attention than the alkene-based process.

In order to achieve the 4-alkynal to cyclopentenone

conversion, the hydroacylation mechanism must involve an unusual trans addition of the rhodium hydride across the alkyne.

An impressive range of substituents could be tolerated, including pendent alkene and alkyne functionalities. The choice of catalyst and solvent was found to be crucial to the success of these reactions.

Tanaka, K.; Fu, G. C. J. Am. Chem. Soc. 2001, 123, 11492.


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Tanaka, K. Chem--Eur. J. 2004, 10, 5681.


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Because no sp3 centers are generated in these reactions, the group has investigated kinetic resolution and desymmetrization procedures.

Tanaka, K.; Fu, G. C. J. Am. Chem. Soc. 2002, 124, 10296.


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Tanaka, K.; Fu, G. C. J. Am. Chem. Soc. 2003, 125, 8078.


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Kokobu, K.; Matsumasa, K.; Miura, M.; Nomura, M. J. Org. Chem. 1997, 62, 4564.

Willis, M. C.; McNally, S. J.; Beswick, P. J. Angew. Chem., Int. Ed. 2004, 43, 340.


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Vy M. Dong. J. AM. CHEM. SOC. 2010, 132, 16330–16333


Wu hua 2011 4 23

Vy M. Dong. J. AM. CHEM. SOC. 2010, 132, 16354–16355


Wu hua 2011 4 23

Tanaka, Ken (8)

Dong, Vy M. (6)

Brookhart, Maurice (5)

Jun, Chul-Ho (5)

Krische, Michael J. (5)

Lenges, Christian P. (5)

Tanaka, Ken (8)

Dong, Vy M. (6)

Brookhart, Maurice (5)

Jun, Chul-Ho (5)

Krische, Michael J. (5)

Lenges, Christian P. (5)

Summary

Tanaka, Ken

Dong, Vy M

Brookhart, Maurice

Jun, Chul-Ho

Krische, Michael J

Lenges, Christian

Glorius, Frank

However, limitations still remain to the transformations that can be achieved; intramolecular reactions to generate rings other than five-membered systems are not

trivial, and the development of an intermolecular process with wide substrate scope has still not been achieved. The development of regio- and enantio-control in intermolecular

reactions is also in its infancy.


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