Novel direct amination of glycerol over heteropolyacid-based catalysts†
The direct amination of glycerol with dimethylamine (DMA) was studied over catalysts based on salts of phosphomolybdic acid. The highest yield of (dimethylamino)acetone (33%) was observed over a catalyst containing 50 wt% of Cs2.5H0.5PMo12O40 supported on a mesoporous silica. The corresponding sample showed good dispersion of the active phase leading to an increased number of available acid sites. With respect to the observed products, a reaction scheme was established explaining notably that the formation of 1,3-bis-dimethylamine-2-propanol and (dimethylamino)propanol was not possible due to the blocking of the required strong acid sites by DMA under reaction conditions.