Volume 54, Issue 23 pp. 6862-6866
Communication

Organocatalyzed CO2 Trapping Using Alkynyl Indoles

Dr. Zhuo Xin

Dr. Zhuo Xin

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.com

Search for more papers by this author
Dr. Camille Lescot

Dr. Camille Lescot

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.com

Search for more papers by this author
Dr. Stig D. Friis

Dr. Stig D. Friis

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.com

Search for more papers by this author
Prof. Dr. Kim Daasbjerg

Prof. Dr. Kim Daasbjerg

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.com

Search for more papers by this author
Prof. Dr. Troels Skrydstrup

Corresponding Author

Prof. Dr. Troels Skrydstrup

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.com

Carbon Dioxide Activation Center (CADIAC), Interdisciplinary Nanoscience Center (iNANO) and Department of Chemistry, Aarhus University, Gustav Wieds Vej 14, 8000 Aarhus (Denmark) http://www.skrydstrup-group.comSearch for more papers by this author
First published: 23 April 2015
Citations: 84

We are grateful to Dr. Jacob Overgaard for the X-ray crystallographic analysis. We are deeply appreciative of generous financial support from the Danish National Research Foundation, (grant no. DNRF118), the Villum Foundation, the Danish Council for Independent Research: Technology and Production Sciences, the Lundbeck Foundation, the Carlsberg Foundation, and Aarhus University. We also thank the Chinese Scholarship Council for a grant to Z.X.

Graphical Abstract

Caught in a trap: The first trapping of CO2 through organocatalyzed CC and CO bond formation is reported. By using alkynyl indoles, this method generates novel indole lactone derivatives by using as little as 5 mol % of the simple organic base 1,5,7-triazabicyclo-[4.4.0]dec-5-ene as an organocatalyst. The transformation shows excellent atom economy and a broad substrate scope, including aromatic, heteroaromatic, and aliphatic 2-alkynyl indoles.

Abstract

The first organocatalyzed trapping of CO2 through CC and CO bond formation is reported. Alkynyl indoles together with catalytic amounts of an organic base and five equivalents of CO2 resulted in the formation new heterocyclic structures. These tricyclic indole-containing products were successfully prepared under mild reaction conditions from aromatic, heteroaromatic, and aliphatic alkynyl indoles with complete regioselectivity. Further investigations suggest that CC bond formation is the initial intermolecular step, followed by lactone-forming CO bond formation.

The full text of this article hosted at iucr.org is unavailable due to technical difficulties.