An attempted cascade radical-mediated cyclisation approach to ring-D aromatic steroids

摘要

A synthetic approach to ring-D aromatic steroids, viz. 5, based on a cascade of radical-mediated cyclisations from the orthoaryl-substituted iododienynones 12 and 13, instead led to the macrocyclic ketone 16 or to the novel bridged tricycle 17, respectively, as the major products.