Synthesis of Nemorosone via a Difficult Bridgehead Substitution Reaction

The synthesis of nemorosone, a polyprenylated acylphloroglucinol isolated from Clusia rosea, was achieved by means of a bridgehead substitution process, involving initial iodination and subsequent lithium-iodine exchange followed by acylation. The difficulties in the bridgehead substitution are discussed, and a probable explanation proposed, based on molecular modelling.