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Updated: Aug 5, 2026

Protocol for the Synthesis of Ortho-trifluoromethoxylated Aniline Derivatives
Published on: January 19, 2016
Synthesis and Reactions of Hydrazine Trifluoroborate Salts
Lorenzo Ballerini1,2, Wenhao Zhao1, Anika Tarasewicz2
1The University of Sheffield, Sheffield, S3 7HF, U.K.
Abstract:
We report a new class of hydrazine trifluoroborate salts that undergo chemoselective reactions to deliver a range of new functionalized building blocks for organic synthesis. In particular, we show that a wide range of pyrazole N-methylboronates can be prepared by condensation reactions with 1,3-dicarbonyl compounds and conjugated ynones with high regiocontrol. Finally, the synthetic potential of these pyrazole derivatives is demonstrated by SEAr, three-component alkyl Petasis Boron-Mannich reaction, and through the synthesis of palovarotene analogs.
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