| Summary: | Solketal is derived from the reaction of acetone with glycerol, a by-product product of the biodiesel industry. We report here the continuous reaction of solketal with anilines over a solid acid niobium phosphate (NbP), for the continuous generation of quinolines in the the well-established Skraup reaction. This study shows that NbP can catalyse all stages of this multistep reaction at 250 °C and 10 MPa pressure, with a selectivity for quinoline of up to 60%. We found that the catalyst eventually deactivates, most probably via a combination of coking and reduction processes but nevertheless we show the promise of this approach. We demonstrated here the application of our approach to synthesize both mono- and bis-quinolines from the commodity chemical, 4,4’-methylenedianiline.
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