Stereoinduction in the Tosyl Radical-Mediated Cyclization of Polysubstituted 1,6-Dienes Derived from D-Glucose and D-Mannose

Radical cyclizations offer an easy access to five- and six-membered rings, and their applications to the synthesis of complex molecules are now incredibly numerous.1 The control of stereochemistry in theses processes is generally high and models have been designed which allow to make fairly good predictions.2-3 Carbohydrates have been used as chiral template for the construction of highly substituted cyclopentane derivatives and they provide a variety of stereochemically well defined starting materials which could be used to evaluate the influence of polysubstituted ethylenic tethers on the stereochemical balance of 5-exo ring closures.