Electro-Generated Acids Catalyzed Epoxyolefin Cyclizations via Cationic Chain Reactions

抄録

We show that a catalytic amount of electro-generated acid (EGA) prepared from the oxidation of a Bu₄NB(C₆F₅)₄/CH₂Cl₂ solution catalyzes effectively the tandem cyclization of epoxyolefins, producing the corresponding polycyclized compounds in 23%–57% yields. The scope and limitations of the substrates are examined, and we compare the stability of the intermediates through theoretical calculations. The success of the current reactions might be due to the high reactivity of EGA, because the counter anion is bulky and stabilized B(C₆F₅)₄⁻ derived from Bu₄NB(C₆F₅)₄ as the supporting electrolyte.