Studies in the claisen rearrangement. Part XII . Synthesis of benzofuro[3,2‐c] [l]‐6a,lla‐dihydro‐lla‐methylbenzopyrans from 1,4‐diaryloxy‐2‐butynes

Abstract
Successful Claisen rearrangement of a number of 1,4‐diaryloxy‐2‐butynes is reported. The products of such a rearrangement are the benzofuro[3,2‐c]benzopyrans. This novel rearrangement offers a facile synthetic route to tetracyclic derivatives resembling the naturally occurring pterocarpans.