In probing of cycloaromatization of 7-phenylsulfonyl-3-hepten-1, 5-diyne systems to generate biradical intermediates under an alkaline condition suggested that the aryl moiety on C3–C4 also plays an important role to switch the Myers cyclization to Schmittel cyclization in the allen–enyne system, although the aryl group on the alkyne terminus does not work in the proceeding of the cycloaromatization. For example, treatment of 1-phenyl-7 ...