Abstract
Ring-opening of epoxide involves two major subjects of study, positional selectivity and stereochemistry. It appears that the reactions with nucleophiles under basic conditions proceed through SN2 type substitution and no serious problem on both mechanism and stereochemistry remains unsolved. In contrast, the results under acidic conditions are confusing. We have critically discussed the mechanisms proposed so far and shown our conclusion. On the basis of this conclusion together with a new concept of microscopic structure of solvation, the wide range changes of stereochemistry of acid catalyzed solvolysis of stilbene oxide from inversion to retention in binary solvents have been explained. This idea might be applicable to the other types of solvolysis.
