Traceless Solid‐Phase Synthesis of Cyclopenta[ c ]quinolines and Cyclopenta[ c ]chromenes via Hetero [6+3] Cycloadditions of Fulvene. A Facile Approach to the 11‐Heterosteroids Framework

The hetero [6+3] cycloaddition of fulvenes to benzoquinones and iodoanilines provides an efficient route to the synthesis of cyclopenta[ c ]‐4H‐chromen‐8‐ol, benzo[ d ]cyclopenta[ e ]‐3H‐3‐azin‐8‐ol and other 11‐hetero steroids. The structure of the cyclopenta[ c ]chromene skeleton was confirmed by the X‐ray structure analysis of the p ‐bromobenzoate of 39 . A small library consisting of 110 examples was prepared by reacting benzoquinones or iodoanilines with resin 17 .