Enhanced catalytic performance in dehydration of sorbitol to isosorbide over a superhydrophobic mesoporous acid catalyst

Synthesis of Isosorbide Esters from Sorbitol with Heterogeneous Catalysts

“…However, with 5 mol% of catalyst, 76 % yield is obtained after only 4 h and the successive side‐reactions are not observed, given that isosorbide yield is not reduced after 24 h (78 %). Hence, the result after 2 h can be considered as representative for TOF calculation, that leads to 4.1 h −1 , better than that previously reported under similar conditions, that probably was underestimated due to the long reaction time. It is also possible to use even only 1 mol% SO 3 H, but the reaction is much slower, with 68 % yield after 24 h, increased to 77 % after 48 h. Under these not fully optimized conditions, 1 mol% catalyst and 24 h reaction time, several sulfonic solids were tested, including different nature of the active sites, alkyl sulfonic, aryl sulfonic and perfluoroalkyl sulfonic.…”

“…On the other hand, the sorbitol dehydration has been also tested in molten state under solvent free conditions, with water elimination under reduced pressure. Different sulfated metal oxides, namely tin oxide, titania and zirconia, have been used as catalysts, as well as some sulfonic solids, either polymeric or silica‐based solids . Whereas the sulfated metal oxides require temperatures in the 180–210 °C range to reach the optimal results of catalytic activity and isosorbide selectivity (75 % with sulfated zirconia at 210 °C), the sulfonic solids allow working at lower temperature (140‐170 °C).…”

Arenesulfonic acid functionalized ordered mesoporous silica as solid acid catalyst for solvent free dehydration of sorbitol to isosorbide

“…The use of sulfonic acid modified OMS as catalyst has been increased for the conversion of biomass-derived carbohydrates due their ordered porous structure and number of accessible Brönsted acid sites [19,20]. However, the proper studies on cyclodehydration of sorbitol to isosorbide using functionalized mesoporous materials are limited [21]. Herein, we synthesized sulfonic acid functionalized OMS having different organic moieties and evaluated their catalyst performance in solvent free cyclodehydration of sorbitol to isosorbide.…”

Isosorbide and dimethyl carbonate: a green match

“…As a result current research on new synthetic approaches for the cyclic sugar isosorbide has been focussed on less toxic and easy to recover heterogeneous acidic catalysts. In particular, mixed oxides [49], phosphated or sulfated oxides [50–56], sulfonic resins [57–59] and bimetallic catalysts [60] have been investigated.…”