Mechanistic investigations of the Ni-catalyzed asymmetric reductive alkenylation of N-hydroxyphthalimide (NHP) esters and benzylic chlorides are reported. Investigations of the redox properties of the Ni-bis(oxazoline) catalyst, the reaction kinetics, and mode of electrophile activation show divergent mechanisms for these two related transformations. Notably, the mechanism of C(sp 3 ) activation changes from a Nimediated process when benzyl chlorides and Mn 0 are used to a reductant-mediated process that is gated by a Lewis acid when NHP esters and tetrakis(dimethylamino)ethylene is used. Kinetic experiments show that changing the identity of the Lewis acid can be used to tune the rate of NHP ester reduction. Spectroscopic studies support a Ni II −alkenyl oxidative addition complex as the catalyst resting state. DFT calculations suggest an enantiodetermining radical capture step and elucidate the origin of enantioinduction for this Ni-BOX catalyst.

The use of a chiral ligand for stereocontrol has assisted the development of a number of asymmetric functionalization of proximal C–H bonds. Herein, we report a chiral ligand-controlled, asymmetric remote meta-C–H activation of arenes, leading to asymmetric C–H olefination and arylation of hydrocinnamic acid derivatives through desymmetrization with Ac-L-Phe-OH as the chiral ligand using a Pd(II) catalyst. The origins of the enantioselectivity were explained with density functional theory calculations. The larger distortion energy of the substrate part in the C–H bond activation transition structure S-TS1 is the major controlling factor that disfavors the formation of the S-enantiomer product.

Rh(iii)-catalyzed coupling of phenylhydrazines with 1-alkynylcyclobutanols was realized through a hydrazine-directed C–H functionalization and [4+1] annulation pathway.

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