Reported is an asymmetric reductive dicarbofunctionalization of unactivated alkenes.U nder the catalysis of aN i/BOXs ystem, various aryl bromides,i ncorporating ap endant olefinic unit, were successfully reacted with an arrayo fp rimary alkylb romides in the presence of Zn as ar eductant, furnishing as eries of benzene-fused cyclic compounds bearing aquaternary stereocenter in high enantioselectivities.N otably,t his reaction avoids the use of pregenerated organometallics and demonstrates high tolerance of sensitive functionalities.T he preliminary mechanistic investigations reveal that this Ni-catalyzed reaction proceeds as acascade consisting of migratory insertion and cross-coupling with an ickel(I)-mediated intramolecular 5-exo cyclization as the enantiodetermining step.Asymmetric difunctionalizations of unactivated alkenes are among the most important reactions in organic synthesis,a s diverse optically active compounds can be accessed in asingle step using simple olefins as precursors.T ransition-metal catalysis has proven to be ap owerful tool for dicarbofunctionalizations of unactivated alkenes including diarylation, dialkylation as well as arylalkylation, and tremendous advances have been achieved recently using both redox-neutral [1][2][3] and reductive strategies. [4] However,a symmetric versions of these reactions are still rare.I nt he field of diarylation, Sigman et al. developed aP d-catalyzed enantioselective diphenylation of 1,3-dienes, [3c] while Brown and his coworker reported aC u-promoted asymmetric diarylation of pendant olefins tethered on aryl boronates. [2d] Recently,L iu et al. achieved Cu-catalyzed enantioselective dicarbofuntionalizations of styrenes involving the installation of aC F 3 moeity. [3d,j] Furthermore,F ue tal. accomplished an enantioselective variant of the two-component arylalkylation. [2b] In this Ni-catalyzed reaction, arylboranes incorporating aterminal olefinic unit were reacted with unactivated alkyl halides, affording various benzofurans and indanes in high enantioselectivities (Scheme 1A). However,a ll the aforementioned asymmetric dicarbofunctionalizations of unactivated olefins require the use of pregenerated organometallics as coupling partners,and is less desirable from the viewpoint of both stepeconomy and functionality tolerance.On the contrary,t he reductive strategy of dicarbofunctionalizations of C À Cd ouble bonds allows the incorporation of two carbo moieties directly from either aryl or alkyl halides with the assistance of ar educing agent, and thus eliminates the additional step of preparation of sensitive organometallics,a sw ell as the related issue of functional-group compatibility.D espite rapid progresses in this area, the asymmetric version of reductive dicarbofunctionalization of unactivated olefins still remains elusive. [5,6] Very recently,o ur group reported ar acemic version of Ni-catalyzed reductive arylalkylation of unactivated alkenes tethered to aryl bromides. [4i] In this context, we report asignificant advance of our method as w...

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Reported is a nickel-catalyzed reductive arylalkylation of unactivated alkenes tethered to aryl iodides with redox active N-hydroxyphthalimide esters as the alkyl source through successful merging of migratory insertion and decarboxylative cross-coupling in a cascade. This new method avoids the use of pregenerated organometallic reagents and thus enables the synthesis of diverse benzene-fused carbo- and heterocyclic compounds with high tolerance of a wide range of functional groups.

The plant cytoskeleton, consisting of actin filaments and microtubules, is a highly dynamic filamentous framework involved in plant growth, development, and stress responses. Recently, research has demonstrated that the plant cytoskeleton undergoes rapid remodeling upon sensing pathogen attacks, coordinating the formation of microdomain immune complexes, the dynamic and turnover of pattern-recognizing receptors (PRRs), the movement and aggregation of organelles, and the transportation of defense compounds, thus serving as an important platform for responding to pathogen infections. Meanwhile, pathogens produce effectors targeting the cytoskeleton to achieve pathogenicity. Recent findings have uncovered several cytoskeleton-associated proteins mediating cytoskeletal remodeling and defense signaling. Furthermore, the reorganization of the actin cytoskeleton is revealed to further feedback-regulate reactive oxygen species (ROS) production and trigger salicylic acid (SA) signaling, suggesting an extremely complex role of the cytoskeleton in plant immunity. Here, we describe recent advances in understanding the host cytoskeleton dynamics upon sensing pathogens and summarize the effectors that target the cytoskeleton. We highlight advances in the regulation of cytoskeletal remodeling associated with the defense response and assess the important function of the rearrangement of the cytoskeleton in the immune response. Finally, we propose suggestions for future research in this area.

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