CC BY-ND-NC 4.0 · Synthesis 2019; 51(01): 185-193
DOI: 10.1055/s-0037-1610412
short review
Copyright with the author

7-Azaindoline Auxiliary: A Versatile Attachment Facilitating Enantioselective­ C–C Bond-Forming Catalysis

Institute of Microbial chemistry (BIKAKEN), 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan   Email: nkumagai@bikaken.or.jp   Email: mshibasa@bikaken.or.jp
,
Institute of Microbial chemistry (BIKAKEN), 3-14-23 Kamiosaki, Shinagawa-ku, Tokyo 141-0021, Japan   Email: nkumagai@bikaken.or.jp   Email: mshibasa@bikaken.or.jp
› Author Affiliations
This work was financially supported by ACT-C (JPMJCR12YO) from JST, and KAKENHI (25713002, 17H03025, and JP16H01043 in Precisely Designed Catalysts with Customized Scaffolding) from JSPS. NK thanks The Naito Foundation for financial support.
Further Information

Publication History

Received: 14 November 2018

Accepted: 16 November 2018

Publication Date:
30 November 2018 (online)


Published as part of the 50 Years SYNTHESIS – Golden Anniversary Issue

Abstract

This short review provides an overview of 7-azaindoline auxiliaries in asymmetric catalysis. 7-Azaindoline serves as a useful attachment to carboxylic acids, and the thus-formed 7-azaindoline amides are amenable to atom-economical C–C bond-forming reactions with high stereoselectivity. The attachment is used for the sake of gaining traction in promoting the reaction of interest and can be easily removed after enantioselective reactions. Both nucleophilic and electrophilic catalyses are realized with broad tolerance for functional groups, showcasing the usefulness of 7-azaindoline auxiliaries for practical and streamlined synthesis of a wide range of acyclic chiral building blocks.

1 Introduction

2 7-Azaindoline as a Key Auxiliary

3 7-Azaindoline Amide as a Pronucleophile

3.1 α-Carbon-Substituted 7-Azaindoline Amide

3.2 α-Nitrogen-Substituted 7-Azaindoline Amide

3.3 α-Oxygen-Substituted 7-Azaindoline Amide

3.4 α-Fluorocarbon-Substituted 7-Azaindoline Amide

3.5 α-Halogen-Substituted 7-Azaindoline Amide

3.6 α-Sulfur-Substituted 7-Azaindoline Amide

4 7-Azaindoline Amide as an Electrophile

4.1 Conjugate Addition of Butenolides

4.2 1,3-Dipolar Cycloaddition of Nitrones

5 Transformation of 7-Azaindoline Amide

6 Conclusion