Scope of the Thermal Cyclization of Nonconjugated Ene–Yne–Nitrile System: A Facile Synthesis of Cyanofluorenol Derivatives

Thermal cyclizations of nonconjugated ene–diyne–nitrile 1 and ene–triyne–nitrile 2 systems were examined and proved to yield not azafluorenol, but cyanofluorenol derivatives (9 and 11, respectively), indicating that the cyano groups do not participate in the radical cycloaromatization but do play important roles to determine the mode of cyclization.