Amphoteric Borylketenimines: Versatile Intermediates in the Synthesis of Borylated Heterocycles

5 years ago

Amphoteric Borylketenimines: Versatile Intermediates in the Synthesis of Borylated Heterocycles

Kowan T. V. O'Keefe, Rodrigo Mendoza-Sanchez, Andrei K. Yudin, Sherif J. Kaldas

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. Access to novel borylated azetidimines, iminocoumarins, amides, iminooxetanes, and amidines is provided by in situ trapping of amphoteric borylketenimine intermediates with various nucleophiles. The described strategy offers high levels of chemo- and regioselectivity. This work highlights the unexplored utility of borylketenimines in the synthesis of potentially bioactive molecules.

Publisher URL: http://onlinelibrary.wiley.com/resolve/doi

DOI: 10.1002/chem.201702008