The Nazarov cyclization is a cationic electrocyclic reaction that, although initially found to be promoted by strong protic acids, has since been shown to be promoted by milder, Lewis acids (the reaction may also be promoted photochemically). 1 Since this discovery, the scope of the reaction has been increased, most notably by Denmark's silicon-directed reaction 2 and West's “interrupted” Nazarov reaction. 3 However, asymmetric induction has not been widely ...
