Optically active organoboronic acids and their derivatives are an important family of target compounds in organic chemistry, catalysis, and medicinal chemistry. Yet there are rare asymmetric catalytic examples reported for the synthesis of these compounds via atom and step economic ways. Herein, we report a chelate-directed iridium-catalyzed asymmetric C(sp 2 )−H borylation of aromatic C−H bonds directed by free amine groups. The success of these transformations relies on a novel family of chiral bidentate boryl ligands (L). They can be synthesized straightforwardly in three steps starting from readily available (S,S)-1,2diphenyl-1,2-ethanediamie ((S,S)-DPEN). The Ir-catalyzed C(sp 2 )−H borylation comprises two parts. The first part is desymmetrization of prochiral diarylmethylamines. In the presence of L3/Ir, a vast array of corresponding borylated products were obtained with high regioselectivity and good to excellent enantioselectivities (26 examples, up to 96% ee). The second part, kinetic resolution of racemic diarylmethylamines, was also conducted. Good selectivity values (up to 68%, 11 examples) were obtained when L8 was used. We also demonstrated the synthetic utility of the current method on gram-scale reaction for several transformations.

Ferrocenes with planar chirality are an important class of privileged scaffolds for diverse chiral ligands and organocatalysts. The development of efficient catalytic asymmetric methods under mild reaction conditions is a long-sought goal in this field. Though many transition-metal-catalyzed asymmetric C–H activation methods have been recorded during the last decade, most of them are related to C–C bond-forming reactions. Owing to the useful attribute of the C–B bond, we herein report an amide-directed iridium-catalyzed enantioselective dual C–H borylation of ferrocenes. The key to the success of this transformation relies on a chiral bidentate boryl ligand and a judicious choice of a directing group. The current reaction could tolerate a vast array of functionalities, affording a variety of chiral borylated ferrocenes with good to excellent enantioselectivities (35 examples, up to 98% enantiomeric excess). We also demonstrated the synthetic utility by preparative-scale reaction and transformations of a borylated product. Finally, on the basis of the observed experimental data, we performed DFT calculations to understand its reaction pathway and chiral induction, which reveals that methyl C­(sp3)-H borylation is crucial to conferring high enantioselectivity through an amplified steric effect caused by an interacted B–O fragment in the transition state.

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