Porous Silica Beads Supported TEMPO and Adsorbed NOx (PSB‐TEMPO/NOx): An Efficient Heterogeneous Catalytic System for the Oxidation of Alcohols under Mild Conditions

The combination of NO_x gas which is stored in the pore canals of porous silica beads (PSB) with a heterogeneous catalyst, PSB‐supported 2,2,6,6‐tetramethylpiperdine 1‐oxyl (PSB‐TEMPO, 1 ), afforded a highly efficient, widely applicable, and efficiently recyclable approach for the selective aerobic oxidation of alcohols. This novel catalytic system (PSB‐TEMPO/NO_x) can be employed in the oxidation of a wide range of alcohols to their corresponding aldehydes and ketones with selectivities as high as 99% at complete conversions under mild conditions. O₂ is the terminal oxidant. PSB‐TEMPO can be recycled for more than 10 times without significant loss of activity.