Investigation of the Diastereoselective Cyclization of Bis-sulfonyl Esters

The diastereoselective cyclization of bissulfonyl esters was investigated by varying both the size and the placement of the substituent on the tether adjoining the reacting centers. Substitution at either the α or β position relative to the ester moiety gave diastereomeric ratios of (1−3):1, while γ substitution dramatically increased the diastereomeric ratios to (6−20):1.