Copper-Catalyzed Dehydrogenative Amidation of Light Alkanes

The functionalization of C-H bonds in light alkanes, particularly to form C-N bonds, remains a challenge. We report the dehydrogenative coupling of amides with C1-C4 hydrocarbons to form N-alkyl amide products with tBuOOtBu as oxidant, and a copper complex of a phenanthroline-type ligand as catalyst. The reactions occurred in good yields in benzene or supercritical carbon dioxide as solvents. This strategy allowed for the determination of the relative reactivity of these alkane C-H bonds toward this amination process and showed, in contrast to prior work with larger alkanes, that the reactivity correlated with bond dissociation energies.

Automated summary

This study reports a dehydrogenative coupling reaction to form N-alkyl amides by reacting amides with C1-C4 hydrocarbons, using tBuOOtBu as oxidant and a copper complex as catalyst. The reactions showed good yields in benzene or supercritical carbon dioxide as solvents. Compared to previous studies on larger alkanes, the reactivity in this amination process correlated with bond dissociation energies.