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Published on: November 9, 2019
Amphoteric Borylketenimines: Versatile Intermediates in the Synthesis of Borylated Heterocycles
Sherif J Kaldas1, Kowan T V O'Keefe1, Rodrigo Mendoza-Sanchez1
1Davenport Research Laboratories, Department of Chemistry, University of Toronto, 80 St. George St., Toronto, ON, M5S 3H6, Canada.
Abstract:
We report the first synthesis of amphoteric borylketenimines from ethynyl N-methyliminodiacetic acid (MIDA) boronate and sulfonyl azides via copper catalysis. In situ trapping of these intermediates with various nucleophiles provided access to novel borylated azetidimines, iminocoumarins, amides, iminooxetanes, and amidines. The described strategy based on borylketenimines offers high levels of chemo- and regioselectivity, enabling the synthesis of unprecedented borylated molecules. This work highlights the unexplored utility of borylketenimines in the synthesis of potentially bioactive molecules.
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