6533b826fe1ef96bd1284ede

RESEARCH PRODUCT

ChemInform Abstract: Epoxidation of Olefins with a Silica-Supported Peracid.

Rossella MelloMaría Elena González NúñezAna Alcalde-aragonésGregorio Asensio

subject

chemistry.chemical_classificationSilanolchemistry.chemical_compoundAllylic rearrangementchemistryCarboxylic acidStyrene oxidePolymer chemistryAnhydrousSubstrate (chemistry)General MedicineAcceptorCatalysis

description

Anhydrous [2-percarboxyethyl] functionalized silica (2a) is an advantageous oxidant for performing the epoxidation of olefins 1. Epoxides 3 do not undergo the ring-opening reactions catalyzed by the acidic silica surface, except for particularly activated cases such as styrene oxide. The hydrophilic and acidic character of the silica surface does not interfere with the directing effects exerted by allylic H-bond acceptor substituents. The alkenes 1 carrying hydroxyl groups react with silica-supported peracid 2a faster than unsubstituted alkenes, thus reversing the trend known for reactions with soluble peracids. These results are attributed to the H-bond interactions of substrate 1 with the silanol and carboxylic acid groups bonded to the silica surface.

https://doi.org/10.1002/chin.201251099