Cyclopenta benzofurans synthesis

In the total synthesis of ( )-linderol A, the 6, 5-tricyclic cyclopenta[i>]benzofuran was made by a tandem reaction of a 3-ethoxycarbonylcoumarin derivative with dimethyl sulfoxonium methylide <03JOC1216>. 

The synthetic strategy involving an intramolecular hydroxyl epoxide opening was applied to build up the cyclopenta[i)]benzofuran ring for the total synthesis of the naturally occurring rocaglaol <04OL4595>. 

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