2021-12-16 | Violations. How Nature Circumvents the Woodward–Hoffmann Rules and Promotes the Forbidden Conrotatory 4n + 2 Electron Electrocyclization of Prinzbach’s Vinylogous Sesquifulvalene – J. Am. Chem. Soc. Garrett A. Kukier, Aneta Turlik, Xiao-Song Xue, and K. N. Houk*.