A Pd-catalyzed carboxamide-directed enantioselective 1,2-carboboration reaction of unactivated alkenes with C−H nucleophiles and B 2 Pin 2 has been developed using a second generation of chiral monodentate oxazoline (MOXca) ligand. The MOXca ligand featuring a modular design of a Nlinked carbazole side arm can be readily synthesized from serine and NH-carbazoles and provided further improved enantiocontrol of the AQ-directed nucleopalladation over MOXin ligand. The use of KTFA additive and TFE solvent was critical to obtain high reactivity in this difunctionalization reaction system. Preliminary study showed that 1,2-aminoboration of 3-butenamide with imide N-nucleophiles and B 2 Pin 2 under the same conditions proceeded in good yield and high enantioselectivity.

Palladium-catalyzed enantioselective C(sp 3 )−H functionalization could provide valuable reactions for organic synthesis. While significant progress has been made on monodentate directing-group-mediated (DG-mediated) enantioselective C−H functionalization using amino acid or N-heterocyclebased chiral ligands, methods for enantioselective C(sp 3 )−H functionalization mediated by bidentate DGs have lagged far behind. For Pd-catalyzed C(sp 3 )−H functionalization reactions, 8aminoquinoline (AQ) is a powerful N,N-bidentate auxiliary. The bidentate binding mode of AQ can stabilize high-valent Pd intermediates, enabling challenging transformations through a Pd II/IV catalytic manifold. Recently, Duan reported an enantioselective Pd-catalyzed AQ-directed benzylic C−H arylation of 3arylpropanamides using Pd II catalyst and the BINOL phosphoramide (P V ) ligand. Herein, we report a protocol for Pd-catalyzed AQ-mediated enantioselective benzylic C−H arylation of 3-arylpropanamides using Pd 0 catalyst and the BINOLphosphoramidite (P III ) ligand. These reactions give good to high yield and improved enantioselectivity (up to 95% ee). Mechanistic studies indicate that the reactions proceed via a Pd 0/II catalytic cycle, unprecedented for AQ-directed reactions. DFT calculations suggest that both the phosphoramidite ligand and cesium carbonate base are involved in the enantiodetermining C−H palladation step, and that the AQ directing group converts between binding modes to accommodate the C−H palladation and reductive elimination steps.

Chiral molecules with multiple stereocenters are widely present in natural products and pharmaceuticals, whose absolute and relative configurations are both critically important for their physiological activities. In spite of the fact that a series of ingenious strategies have been developed for asymmetric diastereodivergent catalysis, most of these methods are limited to the divergent construction of point chirality. Here we report an enantioselective and diastereodivergent synthesis of trisubstituted allenes by asymmetric additions of oxazolones to activated 1,3-enynes enabled by chiral phosphoric acid (CPA) catalysis, where the divergence of the allenic axial stereogenicity is realized by modifications of CPA catalysts. Density functional theory (DFT) calculations are performed to elucidate the origin of diastereodivergence by the stacking- and stagger-form in the transition state (TS) of allene formation step, as well as to disclose a Münchnone-type activation mode of oxazolones under Brønsted acid catalysis.

A chiral aluminum complex controlled, enantioselective nickel-catalyzed domino reaction of aryl nitriles and alkynes proceeding by CÀCN bond activation was developed. The reaction provides various indenes, bearing chiral allcarbon quaternary centers, under mild reaction conditions in yields of 32 to 91 % and ee values within the 73-98 % range. The reaction mechanism and aspects of stereocontrol were investigated by DFT calculations.

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Enantiopure monohydrosilanes are versatile chiral reagents for alcohol resolution and mechanistic investigation. Herein, we have demonstrated the asymmetric synthesis of monohydrosilanes via an intramolecular hydrosilylation strategy.This protocol is suitable for the synthesis of five-and sixmembered cyclic monohydrosilanes,including aclass of chiral oxasilacycles,w ith excellent diastereo-, regio-, and enantioselectivities.N otably,t he catalyst loading could be reduced to 0.1 mol %which makes this one of the most efficient methods to access chiral monohydrosilanes.M echanistic studies and DFT calculations indicate this Rh-catalyzed intramolecular asymmetric hydrosilylation reaction might proceed via aChalk-Harrod mechanism, and the enantio-determining step was predicted to be oxidative addition of Si À Hb ond.

A chiral Lewis acid accelerated asymmetric Pudovik addition/[1,2]‐phospha‐Brook rearrangement is described by Shunxi Dong, Qian Peng, Xiaoming Feng, and co‐workers in their Research Article (e202203650). Control experiments and theoretical calculations revealed that a synergistic effect of the counterion and water was critical for the regio‐ and enantioselective protonation after the [1,2]‐phospha‐Brook rearrangement.

A highly enantioselective tandem Pudovik addition/[1,2]‐phospha‐Brook rearrangement of α‐alkynylketoamides with diarylphosphine oxides was achieved with a N,N′‐dioxide/ScIII complex as the catalyst. This protocol features broad substrate scope, high regio‐ and enantioselectivity, and good functional‐group compatibility, providing a straightforward route to various trisubstituted allenes with a diarylphosphinate functionality in good yields with high enantioselectivities (up to 97 % yield, 96 % ee). Control experiments and theoretical calculations revealed that a synergistic effect of the counterion and water was critical for the regio‐ and enantioselective protonation after [1,2]‐phospha‐Brook rearrangement. The synthetic utility of this methodology was demonstrated by the conversion of products into complex bridged polycyclic architectures through intramolecular dearomatizing arene/allene cycloaddition.