Catalytic access to anhydrohexitols and their isomerization

Anhydrohexitols are industrially relevant and agro-based polyhydroxylated derivatives. Isosorbide and sorbitans are obtained from sorbitol and are used for the production of surfactants, plasticizers and solvents. Isomannide and isoidide are stereoisomers of isosorbide with a high industrial potential which is hampered essentially by their poor accessibility. The efficient chemical access to these key molecules is an issue for further industrial developments and this has prompted academics and industrials to search for efficient processes. This chapter gives an overview of the industrial interest of anhydrohexitols and more particularly focuses on their synthesis by catalytic means from biobased molecules. Dehydration and isomerization reactions that involve polyols or biopolymers are presented and discussed from the point of view of selectivity issues.