Pd-catalyzed C-H functionalizations promoted by transient directing groups remain largely limited to C-H arylation only. Herein, we report a diverse set of ortho-C(sp)-H functionalizations of benzaldehyde substrates using the transient directing group strategy. Without installing any auxiliary directing group, Pd(II)-catalyzed C-H arylation, chlorination, bromination, and Ir(III)-catalyzed amidation, could be achieved on benzaldehyde substrates. The transient directing groups formed in situ via imine linkage can override other coordinating functional groups capable of directing C-H activation or catalyst poisoning, significantly expanding the scope for metal-catalyzed C-H functionalization of benzaldehydes. The utility of this approach is demonstrated through multiple applications, including late-stage diversification of a drug analogue.

Higher-order cycloadditions, particularly [8+2] cycloadditions, are a straightforward and efficient strategy for constructing significant medium-sized architectures. Typically, configuration-restrained conjugated systems are utilized as 8pcomponents for higher-order concerted cycloadditions. However, for this reason, 10-membered monocyclic skeletons have never been constructed via catalytic asymmetric [8+2] cycloaddition with high peri-and stereoselectivity. Here, we accomplished an enantioselective [8+2] dipolar cycloaddition via the merger of visible-light activation and asymmetric palladium catalysis. This protocol provides a new route to 10membered monocyclic architectures bearing chiral quaternary stereocenters with high chemo-, peri-, and enantioselectivity. The success of this strategy relied on the facile in situ generation of Pd-containing 1,8-dipoles and their enantioselective trapping by ketene dipolarophiles, which were formed in situ via a photo-Wolff rearrangement. Over the past six decades, the importance of higher-order cycloadditions for the construction of medium-sized heterocyclic skeletons has been demonstrated. [1] In this context, since the first work from Doering and Wiley in 1960, [2] a variety of [8+2] cycloadditions have been developed. [3] These transformations usually require configurationrestrained, conjugated 8p-components [4-6] to reduce the reaction complexity and entropic barriers, i.e., to disfavour intramolecular cyclizations and facilitate the periselectivity.

Catalytic asymmetric cycloadditions of ambident Pd-containing dipolar species with nucleophilic dipolarophiles,n amely,i nverse-electron-demand cycloadditions,a re challenging and underdeveloped. Possibly,t he inherent linear selectivity of Pd-catalyzed intermolecular allylations and the lacko fe fficient chiral ligands are responsible for this limitation. Herein, two cycloadditions of such intermediates with deconjugated butenolides and azlactones were accomplished by using anovel chiral hybrid P, S-ligand and hydrogen bonding.B yd oing so,h ighly functionalized, optically active dihydroquinol-2-ones were produced with generally high reaction efficiencies and selectivities.P reliminary DFT calculations were performed to explain the high enantio-and diastereoselectivities.Scheme 1. Reaction development of Pd-containing dipoles with butenolides.Supportinginformation and the ORCID identification number(s) for the author(s) of this article can be found under: https://doi.

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An unprecedented straightforward reductive amidation of chloroalkanes with nitroarenes was readily accomplished by merging iron catalysis with visible light photoredox catalysis. A variety of commercially inexpensive abundant nitroarenes and chloroalkanes...