Nickel-Catalyzed Reductive Alkylation of Heteroaryl Imines
Abstract
A Ni-catalyzed reductive cross-coupling of heteroaryl imines with C(sp³) electrophiles for the preparation of heterobenzylic amines is reported. This umpolung-type alkylation proceeds under mild conditions, avoids the pre-generation of organometallic reagents, and ex-hibits good functional group tolerance. Mechanistic studies are consistent with the imine substrate acting as a redox-active ligand upon coordination to a low-valent nickel center. The resulting Ni-bis(2-imino)heterocycle complexes can engage in alkylation reactions with a variety of C(sp³) electrophiles, giving the heterobenzylic amine products in good yields.
Additional Information
The content is available under CC BY NC ND 4.0 License. This paper is dedicated in memory of our colleague and friend Prof. Robert H. Grubbs. Dr. Scott Virgil and the Caltech Center for Catalysis and Chemical Synthesis are gratefully acknowledged for access to analytical equipment. Fellowship support was provided by the Swiss National Science Foundation (M. B.). S.E.R. is a Heritage Medical Research Institute Investigator and acknowledges financial support from the NIH (R35GM118191). The authors would also like to thank Dr. Nathan Dalleska and the Resnick Sustainability Institute's Water and Environmental Lab for elemental analysis of commercial manganese; Dr. Mona Shahgholi for assistance with mass spectrometry measurements; Dr. Paul Oyala for assistance with X-band EPR measurements; Dr. David E. Hill for invaluable assistance with electroanalytical and spectroelectrochemical experiments; as well as Z. Jaron Tong for helpful discussions on DFT calculations and non-innocent ligand complexes.Attached Files
Submitted - nickel-catalyzed-reductive-alkylation-of-heteroaryl-imines.pdf
Supplemental Material - supporting-information.pdf
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Additional details
- Eprint ID
- 109655
- Resolver ID
- CaltechAUTHORS:20210629-203340595
- Swiss National Science Foundation (SNSF)
- Heritage Medical Research Institute
- R35GM118191
- NIH
- Created
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2021-06-29Created from EPrint's datestamp field
- Updated
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2023-03-24Created from EPrint's last_modified field
- Caltech groups
- Heritage Medical Research Institute, Resnick Sustainability Institute