Bipyridyl-Containing Cadmium–Organic Frameworks for Efficient Photocatalytic Oxidation of Benzylamine

Metal–organic
frameworks (MOFs) have attracted increased
research attention in photocatalysis due to their great potential
in light harvest and conversion. However, the organic transformations
as photocatalyzed by MOFs under mild conditions yet remain a challenge.
Herein, three bipyridyl-containing cadmium–organic frameworks
Cd­(dcbpy) (dcbpy = 2,2′-bipyridine-5,5′-dicarboxylate),
Cd­(bdc)­(bpy) (bdc = 1,4-benzenedicarboxylate; bpy = 2,2′-bipyridyl),
and Cd­(bdc)­(2Me-bpy) (2Me-bpy = 4,4′-dimethyl-2,2′-bipyridyl)
were synthesized for the first time. The bpy-containing Cd-MOFs have
strong light harvest abilities and suitable photocatalysis energy
potentials, making them highly active and selective for the photo-oxidation
of benzylamine to N-benzylbenzaldimine under mild
conditions, i.e., using atmospheric air as oxidant, at room temperature,
and in the absence of any photosensitizer or cocatalyst. It provides
an efficient, economical, and green way for the direct oxidation of
amines to produce imines.