Radical reactions of epoxy esters induced by titanocene chloride

The reductive radical cyclizations of several epoxy esters have been achieved using titanocene chloride. The tether length from the initial radical to the carbonyl acceptor is the key of the reactions. We obtained products from radical cyclization onto carbonyl formate and products from formate and hydrogen elimination. The stereochemical outcome of the 5-exo radical cyclization of two diastereomers is reported. A radical cascade cyclization of an unsaturated epoxy formate is also described.