Synlett 2014; 25(2): 179-192
DOI: 10.1055/s-0033-1340165
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© Georg Thieme Verlag Stuttgart · New York

The Synthesis of Alkaloids Using Transition-Metal-Catalyzed Intramolecular Amination Reactions

Hiroaki Ohno*
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan   Fax: +81(75)7534570   Email: hohno@pharm.kyoto-u.ac.jp   Email: nfujii@pharm.kyoto-u.ac.jp
,
Hiroaki Chiba
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan   Fax: +81(75)7534570   Email: hohno@pharm.kyoto-u.ac.jp   Email: nfujii@pharm.kyoto-u.ac.jp
,
Shinsuke Inuki
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan   Fax: +81(75)7534570   Email: hohno@pharm.kyoto-u.ac.jp   Email: nfujii@pharm.kyoto-u.ac.jp
,
Shinya Oishi
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan   Fax: +81(75)7534570   Email: hohno@pharm.kyoto-u.ac.jp   Email: nfujii@pharm.kyoto-u.ac.jp
,
Nobutaka Fujii*
Graduate School of Pharmaceutical Sciences, Kyoto University, Sakyo-ku, Kyoto 606-8501, Japan   Fax: +81(75)7534570   Email: hohno@pharm.kyoto-u.ac.jp   Email: nfujii@pharm.kyoto-u.ac.jp
› Author Affiliations
Further Information

Publication History

Received: 14 August 2013

Accepted after revision: 02 October 2013

Publication Date:
10 December 2013 (online)


Abstract

Transition-metal-catalyzed reactions have the potential to provide significant improvements to the syntheses of complex target molecules. These reactions can be used to achieve a variety of different atom-economical transformations and cascade reactions and, therefore, provide access to synthetic strategies that would otherwise be unavailable using classical organic chemistry. To exemplify the utility of the latest transition-metal-catalyzed reactions for the construction of important target structures, we have been involved in the total synthesis of natural products bearing widely known chemical scaffolds. In this account, we report our recent studies on the use of a palladium-catalyzed cascade cyclization reaction and a gold(I)-catalyzed hydroamination reaction for the construction of the core structures of alkaloids, as well as their application to the total syntheses of lysergic acid, lysergol, isolysergol, and quinocarcin.

1 Introduction

2 Ergot Alkaloid Synthesis

2.1 Construction of the Core Structure by Palladium-Catalyzed Cascade Cyclization

2.2 Asymmetric Total Syntheses of (+)-Lysergic Acid and ­Related Alkaloids

3 Quinocarcin Synthesis

3.1 Construction of the Core Structure by Gold-Catalyzed ­Hydroamination

3.2 Asymmetric Total Synthesis of (–)-Quinocarcin

4 Concluding Remarks

 
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