M. Shibuya et al., CYCLOAROMATIZATION OF ENEDIYNE MODEL COMPOUNDS VIA A REACTION CASCADETRIGGERED BY HYDROLYSIS OF THE ALPHA-ALKYNYLMALONATES, Tetrahedron letters, 37(6), 1996, pp. 865-868
Diethyl alpha-methoxy-alpha-alkynylmalotate derivatives of cis-enediyn
es were synthesized and they produced toluenebiradicals via the reacti
on cascade triggered by ester hydrolysis. Deuterium labeling studies s
uggested that the reaction involved the self quenching process by fair
ly fast disproportionation of toluene biradicals producing zwitterioni
c species.