文摘
Iron-catalyzed divergent tandem radical annulations of aldehydes with olefins are reported. The new strategy allows the rapid and efficient construction of various multifunctionlized indolines (R = Ar) and dihydropyrans (R = Me), which are significant skeletons in bioactive natural products and pharmaceuticals. The substituents of tertiary amines play vital roles to facilitate the desired transformation. Mechanistic studies on indoline formation disclose that the homolytic cleavage of the carbonyl C鈥揌 bond might be involved in the rate-determining step, while dissociation of the aromatic C鈥揌 bond was most likely included in the product-determining step.