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Updated: Jul 31, 2026
Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents
Xiao-Yang Chen1, Erik J Sorensen1
1Frick Chemistry Laboratory , Department of Chemistry , Princeton University , Princeton , New Jersey 08544 , USA . Email: xc3@princeton.edu ; Email: ejs@princeton.edu ; http://chemists.princeton.edu/sorensen/.
Abstract:
Transition-metal-catalyzed C-H alkylation reactions directed by aldehydes or ketones have been largely restricted to electronically activated alkenes. Herein, we report a general protocol for the Ir(iii)-catalyzed ortho C-H alkylations of (hetero)aromatic aldehydes using alkyl boron reagents as the coupling partner. Featuring aniline as an inexpensive catalytic ligand, the method was compatible with a wide variety of benzaldehydes, heterocyclic aldehydes, potassium alkyltrifluoroborates as well as a few α,β-unsaturated aldehydes. An X-ray crystal structure of a benzaldehyde ortho C-H iridation intermediate was also successfully obtained.
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