Catalytic cascade conversion of furfural to 1,4-pentanediol in a single reactor

The synthesis of bio-based linear diols is the subject of many research studies. However, one of the main obstacles in industrial development is the difficulty in controlling product selectivity. Here, we report the catalytic conversion of furfural to 1,4-pentanediol (PD) in the presence of Ru supported on an ordered mesoporous carbon (CMK-3) under pressure of H-2 and CO2 in water. In contrast to previous catalytic pathways, this work is distinct in that it yields 1,4-PD as an exclusive product, instead of a mixture of 1,2-and 1,5-PD as usual. Under optimized conditions, 1,4-PD was obtained in 90% yield, and in a one-pot reaction, directly from furfural. We disclose that the conversion of furfural to 1,4-PD followed an unusual catalytic route. It implies a bifunctional catalytic pathway based on sequential catalytic hydrogenation reactions and an acid-catalyzed Piancatelli's rearrangement.