64E) 642) be formed in either the E or 2 geometry. We will provide evidence supporting the formation of 6-(E), but ruling out the possible formation of 642) is a difficult problem for which only indirect arguments can be made. A further interesting point concerns the possible electrocyclic closure of 6 to a-methoxybenzocyclobutene (7). Sammes and coworkers7 have studied the reactions of optically active 7 in the presence of maleic anhydride (MA), as ...
