[EN] The pyrochlores (HO)SbTeO (x = 1, 1.1 and 1.25) obtained by ion exchange from KSbTeO oxides were used as catalysts for the conversion of fructose to 5-hydroxymethylfurfural (HMF) in HO/Methyl isobutyl ketone (MIBK). The structure of the resulting compounds as well as the location of the HO units inside the three-dimensional network, were determined by XRD from powder samples. The effect of factors such as reaction time and temperature on the formation of HMF was studied. A fructose conversion of 99% and a yield of 59% were achieved after 120 min of reaction time and at 150 °C temperature. The percentage of substitution of the cations Sb and Te in the position B of the pyrochlore was determinant to achieve the maximum incorporation of HO ions in the pyrochlore structure, which allowed to correlate the density of acidic sites present in the materials and their catalytic activity.

The authors acknowledge financial support from Comunidad de Madrid(Spain) (RESTOENE-2-CMS2013/MAE-2882project) and CSIC(Spain) (201880E029 project). The financial support of Spanish MINECO to the project MAT2017-84496-R