Directed Iron-Catalyzedortho-Alkylation and Arylation: Toward the Stereoselective Catalytic Synthesis of 1,2-Disubstituted Planar-Chiral Ferrocene Derivatives

The iron-catalyzed directed ortho -functionalization of arenes developed to an important method in the field of C–H activation. On the other hand, the iron-catalyzed ortho -functionalization of ferrocenes bearing ortho -directing groups (ODGs) has scarcely been investigated. Herein we present the iron-catalyzed ortho -alkylation and -arylation of ODG-substituted ferrocenes bearing a bidentate ODG with the formation of racemic 1,2-disubstituted ferrocenes in up to 94% yield. The approach toward an enantioselective iron-catalyzed C–H activation resulted in an ortho -phenylation with a promising enantiomeric excess of 46%. The first iron-catalyzed diastereoselective ortho -methylation gave an excellent diastereomeric excess of ≥99%.