ChemRxiv
These are preliminary reports that have not been peer-reviewed. They should not be regarded as conclusive, guide clinical practice/health-related behavior, or be reported in news media as established information. For more information, please see our FAQs.
1/1
0/0

C-H Functionalization Reactions of Unprotected N-Heterocycles by Gold Catalyzed Carbene Transfer

preprint
submitted on 28.03.2020 and posted on 30.03.2020 by Sripati Jana, Claire Empel, Chao Pei, Polina Aseeva, Thanh Vinh Nguyen, Rene Koenigs

The C-H functionalization reaction of N-heterocycles with unprotected N-H group is one of the most step-economic strategies to introduce functional groups without the need of installation and removal of protecting groups. Despite recent significant advances in C-H functionalization chemistry, this strategy remains unsatisfactorily developed. In this report, we disclose a simple and straightforward protocol to allow for the selective C-H functionalization of unprotected double benzannellated N-heterocycles via gold catalyzed carbene transfer reactions (29 examples, up to 86% yield). The scope of the reaction can also be expanded to the corresponding protected heterocycles (37 examples, up to 98% yield), further demonstrating the generality of this method. Mechanistic studies by DFT calculations underpin the importance of the gold catalyst and reveal that the selectivity of this reaction is driven by trace amounts of water present in the reaction mixture.

Funding

Enantioselective transformations and continuous-flow synthesis of fluorinated diazoalkanes

Deutsche Forschungsgemeinschaft

Find out more...

Novel organic architectures and functional materials from tropylium ions

Australian Research Council

Find out more...

History

Email Address of Submitting Author

rene.koenigs@rwth-aachen.de

Institution

RWTH Aachen University

Country

Germany

ORCID For Submitting Author

0000-0003-0247-4384

Declaration of Conflict of Interest

the authors declare no conflict of interest

Exports