The Direct Coupling of Phenols and Amines under Rhodium Catalysis
Contributor(s): Martin Oestreich, Hendrik F. T. Klare, Lucie Finck
Chen K, Kang Q.-K, Li Y, Wu W.-Q, Zhu H, Shi H. Westlake University and Westlake Institute for Advanced Study, Hangzhou, P. R. of China
J. Am. Chem. Soc. 2022; 144: 1144-1151
DOI: 10.1021/jacs.1c12622.
Key words
amines - anilines - cross-coupling - phenols - rhodium catalysis
Significance
A redox-neutral strategy for the dehydrative coupling of phenols and amines enabled by a dimeric cyclopentadienyl rhodium(III) complex is disclosed. The reaction proceeds under mild conditions, releasing water as the sole by-product. This method is also applicable to late-stage functionalization.
Comment
Starting from readily available primary or secondary amines and phenols, this transformation provides access to a wide range of valuable anilines in good yields. Mechanistic experiments support a keto–enol tautomerization of phenol as the key step, facilitated by η6-coordination of the aryl ring by the rhodium complex.
