In an earlier study directed at the synthesis of pleuromutilin 3, we found that it was possible to construct the bridging eight-membered ring by a radical cyclisation starting with xanthate 1 and leading to product 2 in fairly good yield (Scheme 1). 1,2 Such 8-endo radical ring closures are quite rare, 3 but could nevertheless constitute an interesting approach to various polycyclic terpenes containing a cyclooctane sub-unit. In this respect, we examined the possibility of ...
