Free or unfunctionalized benzylamines are well known to participate in C–H activation
in the presence of palladium salts. Despite the ease with which these complexes can
be activated, subsequent functionalization of the dimeric cyclometalates can be challenging.
We demonstrate herein a free primary amine based C–H activation/functionalization
protocol that allows for the ortho-C–H chlorination and bromination of unprotected benzylamines. We also demonstrate
how use of fluorine-based oxidants gives rise to a unique acetoxylation/cyclization
owing to the nucleophilicity of the free primary amine directing group.
Key words
amines - catalysis - halogenation - palladacycles - palladium - oxidation - cyclization
- condensation