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Updated: Aug 28, 2025

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Transformable Transient Directing Group-Assisted C(sp2)-H Activation: Synthesis and Late-Stage Functionalizations of
Bubul Das1, Anjali Dahiya1, Ashish Kumar Sahoo1
1Department of Chemistry, Indian Institute of Technology Guwahati, Guwahati 781039, India.
Abstract:
The isocyanate group in aryl isocyanates serves as a transformable transient directing group in a Ru(II)-catalyzed ortho olefination leading to o-alkenylanilines. In alcoholic solvents, aryl isocyanates are transformed into carbamates, which initiate the insertion of acrylates via o-C-H activation. In particular, AmOH serves the dual role of solvent-cum transient directing mediator. The o-alkenylanilines are converted into azacoumarins and subsequently into C-4 aryl-substituted azacoumarins using aryl iodides as coupling partners via Pd(II)-catalyzed C-H functionalizations.
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