Synlett 2010(13): 1883-1908  
DOI: 10.1055/s-0030-1257988
ACCOUNT
© Georg Thieme Verlag Stuttgart ˙ New York

Searching for Untrodden Paths in Organocatalysis Territory

Guillem Valeroa, Xavier Companyóa, Natalia Bravoa, Andrea-Nekane R. Albaa, Albert Moyano*a, Ramon Rios*a,b
a Departament de Química Orgànica, Universitat de Barcelona, Facultat de Química, C. Martí i Franquès 1-11, 08028 Barcelona, Catalonia, Spain
Fax: +34(93)3397878; e-Mail: amoyano@ub.edu; e-Mail: rios.ramon@icrea.cat;
b ICREA, Pg. Lluis Companys 23, 08010 Barcelona, Catalonia, Spain
Further Information

Publication History

Received 16 April 2010
Publication Date:
03 August 2010 (online)

Abstract

In spite of the tremendous growth experienced by the field of asymmetric organocatalysis in the last decade, it is important to realize that we are still far away from having explored all of the possible pathways in organocatalysis ‘territory’; the application of the organocatalysis concept can still provide new catalysts and reactions for a variety of asymmetric organic transformations. To exemplify this assertion, we summarize the research performed in our laboratory over the past two years which has led to the development of new enantioselective approaches to organometallic compounds, to the desymmetrization of prochiral ketones, to functionalized cyclopropanes and piperidines, to fluorinated compounds, and to quaternary α-amino acids, among others.

1 Introduction

2 Enamine Chemistry

2.1 Ferrocenes: Unprecedented Reactants in Organocatalysis

2.1.1 Organocatalytic Mannich Reactions

2.1.2 Planar Chirality

2.2 Aldol Reaction: Proline-Thiourea Catalysis

2.2.1 Desymmetrization of 4-Substituted Cyclohexanones

2.2.2 Unraveling the Role of the Thiourea Co-catalyst

3 Iminium Chemistry

3.1 Tandem Reactions

3.1.1 Highly Enantioselective Synthesis of Piperidines

3.1.2 Cyclopropanation

3.2 Michael Additions

3.2.1 Anthrones

3.2.2 Fluoromalonates

3.2.3 Sulfones: An Interesting New Tool in Organocatalysis

3.2.3.1 Fluoro-Substituted Sulfones

3.2.3.2 Alkyl Sulfones

3.2.4 Oxindoles

4 Oxazolones: Intriguing Reactants in Organocatalyzed Processes

4.1 Asymmetric Michael Addition of Oxazolones to Nitro­styrenes

4.2 Asymmetric Michael Addition of Oxazolones to Vinyl Sulfones

5 Summary and Outlook

15

When, under the same reaction conditions, the N-(4-methoxyphenyl)imine derivative of benzaldehyde was reacted with butanone, a 1:1.2 mixture of diastereomers (linear/branched) was obtained.