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The Pd-catalyzed, Cu I Àcarboxylate-mediated crosscoupling reactiono fo rganosulfur compounds with nucleophilic organometallic reagents is knowna st he Liebeskind-Srogl cross-coupling reaction. Owing to the readily available starting materials and neutral reactionc onditions, it has become an attractive procedure for the formation of carbonÀcarbon bonds, in particularf or cases in whicht radi-tional methods had failed. Since the seminal work of Liebeskind and Srogl in 2000, this reactionh as received intense attentionf rom the synthetic community.I nt his Focus Review,w eh ighlight recent advances in this intriguing cross-coupling reactiona nd its applications in organic synthesis.Scheme1.Liebeskind-Srogl cross-coupling reaction.Scheme2.The original Liebeskind-Sroglc ross-coupling reaction.d ba = dibenzylideneacetone, TFP = tri-2-furanylphosphine [a] Dr.Scheme4.Cross-coupling reaction between a-amino acid thiol esters and organostannanes. Cbz = benzyloxycarbonyl.Scheme5.Cross-coupling reaction between thiol esters and B-alkyl-9-BBN. 9-BBN = 9-borabicyclo[3.3.1]nonane.Scheme6.One-pothydroboration/intramolecular-cross-couplingr eaction between thiol esters and B-alkyl-9-BBN. DIPEA = N,N-diisopropylethylamine.Scheme7.Cross-coupling reaction between thiol esters andorganoindium reagents.Scheme8.Cross-coupling reaction between thiol esters andorganosilicon reagents. TBAF = tetra-n-butylammonium fluoride.Scheme9.Intramolecular cross-coupling reaction between thiol esters and olefins.Scheme38. Cross-coupling reaction between diaryld isulfides and boronicacids/terminal-alkynes.Scheme55. Synthesis of the C 15 ÀC 36 segment of goniodomin A. TBS = tert-butyldimethylsilyl, TBDPS = tert-butyldiphenylsilyl.Scheme56. To talsynthesis of verbenachalcone. MOM = methoxymethyl.Scheme57. Synthesis of enigmol and its stereoisomers. Boc = tert-butyloxycarbonyl.Scheme58. To talsynthesis of (À)-agelastatins A-F.Scheme59. Synthesis of quinone-containing salvinorin Aa nalogues.Scheme60. Synthesis of Soai-type aldehydes.

We report a dual-tasked methylation that is based on cooperative palladium/norbornene catalysis. Readily available (hetero)aryl halides (39 iodides and 4 bromides) and inexpensive MeOTs or trimethylphosphate are utilized as the substrates and methylating reagent, respectively. Six types of "ipso" terminations can modularly couple with this "ortho" C−H methylation to constitute a versatile methylation toolbox for preparing diversified methylated arenes. This toolbox features inexpensive methyl sources, excellent functional-group tolerance, simple reaction procedures, and scalability. Importantly, it can be uneventfully extended to isotope-labeled methylation by switching to the corresponding reagents CD 3 OTs or 13 CH 3 OTs. Moreover, this toolbox can be applied to late-stage modification of biorelevant substrates with complete stereoretention. We believe these salient and practical features of our dual-tasked methylation toolbox will be welcomed by academic and industrial researchers.

The direct difunctionalization of alkenes, a cheap and abundant feedstock, represents one of the most attractive strategies for increasing molecular complexity in synthetic organic chemistry. In contrast with the 1,2‐difunctionalization of alkenes, recent advances showcase alkene 1,n‐difunctionalizations (n≠2) involving metal migration is an emerging and rapidly growing area of research. This promising strategy not only opens a novel avenue for future development of alkene transformations, but also significantly expands upon the bond disconnections available in modern organic synthesis. This Minireview summarizes recent progress in the migratory difunctionalization of alkenes, with an emphasis on the driving force for metal migration.