On the Importance of an Acid Additive in the Synthesis of Pyrido[1,2‐a]benzimidazoles by Direct Copper‐Catalyzed Amination

Chemistry – A European JournalVolume 17, Issue 23 p. 6315-6320 Communication On the Importance of an Acid Additive in the Synthesis of Pyrido[1,2-a]benzimidazoles by Direct Copper-Catalyzed Amination Dr. Kye-Simeon Masters, Dr. Kye-Simeon Masters Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorTom R. M. Rauws, Tom R. M. Rauws Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorDr. Ashok K. Yadav, Dr. Ashok K. Yadav Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorProf. Dr. Wouter A. Herrebout, Prof. Dr. Wouter A. Herrebout Cryospectroscopy, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)Search for more papers by this authorProf. Dr. Benjamin Van der Veken, Prof. Dr. Benjamin Van der Veken Cryospectroscopy, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)Search for more papers by this authorProf. Dr. Bert U. W. Maes, Corresponding Author Prof. Dr. Bert U. W. Maes [email protected] Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this author Dr. Kye-Simeon Masters, Dr. Kye-Simeon Masters Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorTom R. M. Rauws, Tom R. M. Rauws Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorDr. Ashok K. Yadav, Dr. Ashok K. Yadav Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this authorProf. Dr. Wouter A. Herrebout, Prof. Dr. Wouter A. Herrebout Cryospectroscopy, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)Search for more papers by this authorProf. Dr. Benjamin Van der Veken, Prof. Dr. Benjamin Van der Veken Cryospectroscopy, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium)Search for more papers by this authorProf. Dr. Bert U. W. Maes, Corresponding Author Prof. Dr. Bert U. W. Maes [email protected] Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Organic Synthesis, University of Antwerp, Groenenborgerlaan 171, 2020 Antwerp (Belgium), Fax: (+32) 32653233Search for more papers by this author First published: 20 April 2011 https://doi.org/10.1002/chem.201100574Citations: 125Read the full textAboutPDF ToolsRequest permissionExport citationAdd to favoritesTrack citation ShareShare Give accessShare full text accessShare full-text accessPlease review our Terms and Conditions of Use and check box below to share full-text version of article.I have read and accept the Wiley Online Library Terms and Conditions of UseShareable LinkUse the link below to share a full-text version of this article with your friends and colleagues. Learn more.Copy URL Share a linkShare onEmailFacebookTwitterLinkedInRedditWechat Graphical Abstract Not just an acid! An expedient and highly modular synthesis of 6-, 7-, and 8-substituted pyrido[1,2-a]benzimidazoles (4) has been developed by a direct intramolecular CH amination of N-phenylpyridin-2-amines (3). Efficient CH amination of 3 could only be achieved in the presence of catalytic copper and an acid additive. The type of acid (pKa) proved to be crucial for the catalysis. CCl aminations in N-(2-chloroaryl)pyridin-2-amines allow access to 9-substituted pyrido[1,2-a]benzimidazoles. Supporting Information Detailed facts of importance to specialist readers are published as "Supporting Information". Such documents are peer-reviewed, but not copy-edited or typeset. They are made available as submitted by the authors. Filename Description chem_201100574_sm_miscellaneous_information.pdf1.3 MB miscellaneous_information Please note: The publisher is not responsible for the content or functionality of any supporting information supplied by the authors. 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Soc. 2010, 132, 13217–13219. Citing Literature Volume17, Issue23May 27, 2011Pages 6315-6320 ReferencesRelatedInformation