Cycloaddition of Benzothiete to 4-Substituted Styrenes
By thermal ring opening benzothiete (1) generates an 8-? electron system 2, which forms the cycloadducts 4/5a-j with 4-substituted styrenes 3a-j.The enhancement of the reactivity by electron-donating as well as electron-withdrawing substituents and their influence on the regioselectivity are discussed by applying frontier orbital calculations. - Key Words: Cycloaddition; Substituent effects; Reactivity; Regioselectivity; FMO calculations