Highly regio- and enantioselective rhodium-catalyzed allylic alkylation of 1,3-diketones with racemic secondary allylic alcohols is reported. In the presence of a Rh-catalyst derived from the Carreira (P, olefin)-ligand and TFA as an additive, chiral branched α-allylated 1,3-diketones could be obtained in good to excellent yields, with excellent regio- and enantioselectivity ( b/ l > 19/1, 86-98% ee). The direct utilization of allyl alcohols as electrophiles represents an improvement from the viewpoint of an atom economy. Both aryl- and aliphatic-substituted allyl alcohols are suitable substrates with excellent reaction outcomes. This reaction features mild conditions, broad substrate scope, and readily available substrates.

A novel rhodium‐catalyzed dearomatization of O‐substituted pyridines to access N‐substituted 2‐pyridones has been developed. A computational study suggests a mechanism involving the formation of a pyridinium ylide followed by an unprecedented 1,4‐acyl migratory rearrangement from O to C. Furthermore, the chiral dirhodium complexes serve as the catalyst for the asymmetric transformation with excellent enantioselective control. DFT calculations indicate the chirality is transferred from axial chirality to the central stereogenic centre. The stronger π–π interaction and CH–π interaction account for the high enantioselectivity.

Asymmetric carbene insertion reactions represent one of the most important protocols to construct carbonheteroatom bonds. The use of donor-acceptor diazo compounds bearing an ester group is however a prerequisite for achieving high enantioselectivity. Herein, we report a chemoand enantioselective formal N À H insertion of 2-pyridones that has been accomplished for the first time with enynones as the donor-donor carbene precursors. DFT calculations indicate an unprecedented enantioselective 1,4-proton transfer from O to C. The rhodium catalyst provides a chiral pocket in which the steric repulsion and the p-p interaction of the propeller ligand play a critical role in determining the selectivities.

A rhodium-catalyzed reaction of N-hydroxyanilines with diazo compounds to produce α-imino esters was developed. Distinct from the commonly accepted 1,2-H transfer for normal X−H insertion reactions, density functional theory calculations indicate that this transformation proceeds via a novel rebound hydrolysis mechanism. Furthermore, a three-component reaction was explored to synthesize highly functionalized β-lactams in good yields and diastereoselectivities.