Cascade radical-mediated cyclisations with conjugated ynone electrophores. An approach to the synthesis of steroids and other novel ring-fused polycyclic carbocycles
作者:Gerald Pattenden、Davey A. Stoker、Nicholas M. Thomson
DOI:10.1039/b703373g
日期:——
A cascade radical-mediated Diels-Alder reaction with the iododienynone 16b produced the tricyclic ketone 17 (22%). By contrast, treatment of the substituted furans 36 and 47 with Bu(3)SnH-AIBN, instead led to the tetracycles 44 and 58 respectively, rather than the anticipated oestranes, i.e. 38 and 48. In a separate study, attempted cascade radical-mediatedcyclisations from the ortho-aryl substituted