Mesoporous Structured Silica - An improved catalyst for direct amide synthesis and its application to continuous flow processing

We recently published details of an effective, reusable and benign heterogeneous amidation catalyst based on thermal treatment of amorphous K60 silica, however the loading of catalyst required was high for some reactions. We report herein our further development of a series of heterogeneous catalysts based on structured silica (SBA) that retain all the green credentials of the previously described amorphous silica, but with increased efficiency. These catalysts were then utilised in continuous flow systems, achieving excellent conversions with dramatically reduced reaction times.