Preparation of polysubstituted isochromanes by addition of ortho-lithiated aryloxiranes to enaminones.

The reaction of ortho-lithiated aryloxiranes with various enaminones straightforwardly affords new functionalized isochromanes as mixtures of two epimeric stereoisomers in reasonable to very good yields (50-90%). The two diastereomers, which show a high structural variability, can be easily separated by column chromatography.