ReO x /TiO2: A Recyclable Solid Catalyst for Deoxydehydration

Deoxydehydration (DODH) enables the transformation of two adjacent hydroxyl functions into a C–C double bond: e.g., facilitating synthesis of 1,3,5-hexatriene from sorbitol. Here we report the first stable heterogeneous catalyst for DODH based on ReO x supported on TiO2. ReO x /TiO2 exhibits not only catalytic activity and selectivity comparable to those of previously described molecular rhenium catalysts but also excellent stability without deactivation over at least six consecutive runs. X-ray absorption spectroscopy (XAFS) measurements indicate a mixture of Re­(VII), Re­(IV), and Re(0) species at a ratio of 0.47:0.27:0.25, remaining comparatively stable during catalysis.