Synthesis of 7a‐aryl‐5‐t‐butyl‐3‐methyleneoctahydrobenzofuran possessing partial skelotons of some santonin analogue and furanolignans by intramolecular radical cyclisation reaction

Abstract

Bicyclic octahydrobenzofuran derivatives (1c‐6c) possessing the partial skeletons of santonin (7), 11,13‐dehydroisohyposantonin (8), dihydrosesamin (9) and lariciresinol (10) have been synthesised by intramolecular radical cyclisation in good yield via the precursors viz., the trans diaxial bromopropynyl ethers (1b‐6b) obtained in highly regio/stereoselective manner.