Iodine(iii)-mediated oxidative intramolecular arene–alkene coupling exemplified in the synthesis of phenanthrenes

Abstract

An iodine(III)-mediated synthesis of substituted phenanthrenes from ortho-vinylated biaryl derivatives through highly 6-endo-trig selective oxidative intramolecular arene–alkene coupling is reported. The title method allows for the construction of diversely functionalized target compounds under very mild conditions and in yields ranging up to 79%. Preliminary mechanistic investigations indicate that the reaction presumably proceeds via activation of the alkene moiety followed by a Friedel–Crafts-type electrophilic aromatic substitution at the adjacent arene ring.