Recent Advances in Asymmetric [3,3]-Sigmatropic Rearrangements

Udo Nubbemeyer

doi:10.1055/s-2003-39171

REVIEW

Recent Advances in Asymmetric [3,3]-Sigmatropic Rearrangements

Udo Nubbemeyer
Institut für Organische Chemie und Abteilung für Lehramtskandidaten, Fachbereich Chemie und Pharmazie, Johannes Gutenberg-Universität, Duesbergweg 10-14, 55099 Mainz, Germany
Fax: +49(6131)3924533; e-Mail: nubbemey@mail.uni-mainz.de;

Abstract

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Abstract

The synthesis of new complex structures is still a challenge in preparative organic chemistry. Focusing on the generation of defined stereogenic centers, the [3,3]-sigmatropic rearrangements are known as reliable reactions. Always, a highly ordered transition state must be passed through, which allows the shift of chiral information from the reactant into the nascent product. Generally, the complete [1,3]- and, frequently, the [1,4]-chirality transfer enables one to predict the configuration of the new centers.

This review focuses on Claisen and Cope rearrangements, which adopt the chiral information via a so termed asymmetric induction. This means, that the directing chiral subunit is placed outside of the six centers of the rearrangement system being reorganized during the course of the [3,3]-sigmatropic reaction.

Reviewing the literature since 1995, enantioselective Claisen rearrangements have been widely investigated. The unique sense of the reaction allows the conversion of an easily accessible C atom-heteroatom bond into a new C-C bond making this rearrangement useful for constructing complex molecules. In contrast, the Cope rearrangement is reversible. One crucial requirement is to force the process to completion with respect to the desired product. Hence ‘enantioselective Cope rearrangements’ are always included as one step in a reaction cascade to guarantee the unique sense of the process. Analyzing such reactions in more detail, the chirality-inducing step is run prior to the Cope rearrangement. Thus, the [3,3]-sigmatropic rearrangement is conducted under the well-known [1,3]-chirality transfer conditions.

1 Introduction
2 Asymmetric Claisen Rearrangements: Classification
3 Remote Stereocontrol in Claisen Rearrangements
3.1 Stereogenic Center at C1
3.2 Stereogenic Center at C6
3.3 Stereogenic Center in Other Positions
4 Auxiliary Control in Claisen Rearrangements
4.1 Auxiliary Attached to Position X
4.2 Auxiliary Attached to Position Y
4.3 Auxiliary Attached to Position Z
4.4 Miscellaneous
5 Chiral Metal Complex Directed Claisen Rearrangements
6 Enantioselective Catalyzed Claisen Rearrangements
7 Asymmetric Cope Rearrangements
7.1 Remote Stereocontrol in Cope Rearrangements
7.2 Auxiliary Control in Cope Rearrangements
7.3 Catalyst Control in Cope Rearrangements
8 Summary

Key words

asymmetric Claisen rearrangement - Cope rearrangement - chiral auxiliary - chiral metal complex - chiral catalyst

Full Text

References

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<A NAME="RE08002SS-68">68</A> Kang J. Yew KH. Kim TH. Choi DH. Tetrahedron Lett. 2002, 43: 9509

<A NAME="RE08002SS-69A">69a</A> Jiang Y. Lougmire JM. Zhang X. Tetrahedron Lett. 1999, 40: 1449

<A NAME="RE08002SS-69B">69b</A> Leung P.-H. Ng K.-H. Li Y. White AJP. Williams DJ. J. Chem. Soc., Chem. Commun. 1999, 2435

<A NAME="RE08002SS-69C">69c</A> Uozumi Y. Kato K. Hayashi T. Tetrahedron: Asymmetry 1998, 9: 1065

<A NAME="RE08002SS-70">70</A> Gais H.-J. Böhme A. J. Org. Chem. 2002, 67: 1153

For an aza-Cope-Mannich tandem process see:

<A NAME="RE08002SS-71A">71a</A> Knight SD. Overman LE. Pairaudeau G. J. Am. Chem. Soc. 1995, 117: 5776

For oxy-Cope-aldol tandem process see ref. [1i]

<A NAME="RE08002SS-72">72</A> Low stereoselectivities were observed in several anionic oxy-Cope rearrangements: Lee Y. Lee YR. Moon O. Kwon O. Shim MS. Yun JS. J. Org. Chem. 1994, 59: 1444

For an example where a chiral chromium arene complex did not affect the stereochemical outcome of a Cope rearrangement see:

<A NAME="RE08002SS-73A">73a</A> Mandal SK. Sarkar A. J. Chem. Soc., Perkin Trans. 1 2002, 669

<A NAME="RE08002SS-73B">73b</A> For an aza-Cope rearrangement via chromium carbene complexes see: Barluenga J. Tomas M. Ballesteros A. Santamaria J. Suarez-Sobrino A. J. Org. Chem. 1997, 62: 9229

<A NAME="RE08002SS-74A">74a</A> Kuehne ME. Xu F. J. Org. Chem. 1997, 62: 7950

<A NAME="RE08002SS-74B">74b</A> Kuehne ME. Xu F. J. Org. Chem. 1998, 63: 9427

<A NAME="RE08002SS-74C">74c</A> Kuehne ME. Xu F. J. Org. Chem. 1998, 63: 9434

<A NAME="RE08002SS-75">75</A> Deloisy S. Kunz H. Tetrahedron Lett. 1998, 39: 791

<A NAME="RE08002SS-76A">76a</A> Cardoso AS. Lobo AM. Prabhakar S. Tetrahedron Lett. 2000, 41: 3611

<A NAME="RE08002SS-76B">76b</A> Depew KM. Danishefsky SJ. Rosen N. Sepp-Lorenzino L. J. Am. Chem. Soc. 1996, 118: 12463

The 3,5-rearrangement can be described as an iminium salt olefin addition and a subsequent fragmentation (cation stabilization). No new stereogenic center was constructed.

<A NAME="RE08002SS-78">78</A> Román E. Baños M. Higes FJ. Serrano JA. Tetrahedron: Asymmetry 1998, 9: 449

<A NAME="RE08002SS-79">79</A> Agami C. Couty F. Puchot-Kadouri C. Synlett 1998, 449

<A NAME="RE08002SS-80A">80a</A> Nokami J. Ohga M. Nakamoto H. Matsubara T. Hussain I. Kataoka K. J. Am. Chem. Soc. 2002, 123: 9168

<A NAME="RE08002SS-80B">80b</A> For preliminary publications see: Nokami J. Anthony L. Sumida S. Chem.-Eur. J. 2000, 6: 2909 ; concept

<A NAME="RE08002SS-80C">80c</A> See also: Sumida S. Ohga M. Mitani J. Nokami J. J. Am. Chem. Soc. 2000, 122: 1310

<A NAME="RE08002SS-80D">80d</A> Nokami J. Yoshizane K. Matsuura H. Sumida S. J. Am. Chem. Soc. 1998, 120: 6609

<A NAME="RE08002SS-80E">80e</A> Semeyn C. Blaauw RH. Hiemstra H. Speckamp WN. J. Org. Chem. 1997, 62: 3426

<A NAME="RE08002SS-80F">80f</A> For a recent publication (1,3 chirality transfer in 2-oxonia Cope rearrangements see: Loh T.-P. Hu Q.-Y. Ma L.-T. Org. Lett. 2002, 4: 2389

The reversibility of the Cope rearrangement might cause some racemization - the avoiding of such a process was recommended. Alternatively a Prins cyclization could be discussed as the basic reaction mechanism. Cope rearrangements were found to be much faster than the Prins reaction. For the role of oxonia Cope rearrangements in Prins cyclizations see:

<A NAME="RE08002SS-81A">81a</A> Rychnovsky SD. Marumoto S. Jaber JJ. Org. Lett. 2001, 3: 3815

<A NAME="RE08002SS-81B">81b</A> Marumoto S. Jaber JJ. Vitale JP. Rychnovsky SD. Org. Lett. 2002, 4: 3919

<A NAME="RE08002SS-82A">82a</A> Allin SM. Baird RD. Lins RJ. Tetrahedron Lett. 2002, 43: 4195

<A NAME="RE08002SS-82B">82b</A> Allin SM. Button MAC. Baird RD. Synlett 1998, 1117

<A NAME="RE08002SS-82C">82c</A> Allin SM. Button MAC. Tetrahedron Lett. 1998, 39: 3345-3348

<A NAME="RE08002SS-82D">82d</A> For preliminary publications see: Allin SM. Button MAC. Shuttleworth SJ. Synlett 1997, 725

n-BuLi was found to be the base of choice to induce the anionic amino Cope rearrangements. Experiments using alternative strong bases such as LDA and KHMDS failed.

<A NAME="RE08002SS-84A">84a</A> Young Yoo H. Houk KN. Lee JK. Scialdone MA. Meyers AI. J. Am. Chem. Soc. 1998, 120: 205

<A NAME="RE08002SS-84B">84b</A> Dobson HK. LeBlanc R. Perrier H. Stephenson C. Welch TR. Macdonald D. Tetrahedron Lett. 1999, 40: 3119

<A NAME="RE08002SS-84C">84c</A> Allin SM. Button MAC. Tetrahedron Lett. 1999, 40: 3801

<A NAME="RE08002SS-85">85</A> Tomooka K. Nagasawa A. Wei S.-Y. Nakai T. Tetrahedron Lett. 1996, 37: 8899

In contrast to the Oppolzer sultams the corresponding Evans auxiliary gave only moderate chiral induction of about 50% de building-up the new stereogenic center.

<A NAME="RE08002SS-87">87</A> Tomooka K. Nagasawa A. Wei S.-Y. Nakai T. Tetrahedron Lett. 1996, 37: 8995

<A NAME="RE08002SS-88A">88a</A> Schneider C. Rehfeuter M. Tetrahedron Lett. 1998, 39: 9

<A NAME="RE08002SS-88B">88b</A> Black WC. Giroux A. Greidanus G. Tetrahedron Lett. 1996, 37: 4471

<A NAME="RE08002SS-89">89</A> Paquette LA. Tae J. J. Org. Chem. 1998, 63: 2022

<A NAME="RE08002SS-90">90</A> Davies HML. Ahmed G. Churchill MR. J. Am. Chem. Soc. 1996, 118: 10774

For potential catalysts see:

<A NAME="RE08002SS-91A">91a</A> Helmchen G. Pfaltz A. Acc. Chem. Res. 2000, 33: 336

<A NAME="RE08002SS-91B">91b</A> Fache F. Schulz E. Tommasino ML. Lemaire M. Chem. Rev. 2000, 100: 2159

<A NAME="RE08002SS-92A">92a</A> Davies HWL. Hodges ML. J. Org. Chem. 2002, 65: 5683

<A NAME="RE08002SS-92B">92b</A> Davies HML. Doan BD. J. Org. Chem. 1999, 64: 8501

<A NAME="RE08002SS-92C">92c</A> Davies HML. Stafford DG. Doan BD. Houser JH. J. Am. Chem. Soc. 1998, 120: 3326

<A NAME="RE08002SS-92D">92d</A> Davies HML. Doan BD. Tetrahedron Lett. 1996, 37: 3967

<A NAME="RE08002SS-92E">92e</A> For a racemic series synthesizing azabicyclo[3,2,2]nonanes see: Davies HML. Hodges LM. Thornley CT. Tetrahedron Lett. 1998, 39: 2707

<A NAME="RE08002SS-92F">92f</A> Syntheses of tremulenolides: Davies HML. Doan BD. J. Org. Chem. 1998, 63: 657

For a mechanistic discussion concerning the stereochemical outcome of the asymmetric catalyzed cyclopropanation see the original references.

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