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Despite the paramount importance of the Suzuki–Miyaura coupling (SMC) in academia and industry, and the great promise of iron to offer sustainable catalysis, iron‐catalyzed SMC involving sp3‐hybridized partners is still in its infancy. We herein report the development of a versatile, well‐defined electron‐deficient anilido‐aldimine iron(II) catalyst. This catalyst effectively performed C(sp3)−C(sp2) and C(sp3)−C(sp3) SMC of alkyl halide electrophiles and (hetero)aryl boronic ester and alkyl borane nucleophiles respectively, in the presence of a lithium amide base. These couplings operated under mild reaction conditions and displayed wide functional group compatibility including various medicinally relevant N‐, O‐ and S‐based heterocycles. They also tolerated primary, secondary and tertiary alkyl halides (Br, Cl, I), electron‐neutral, ‐rich and ‐poor boronic esters and primary and secondary alkyl boranes. Our methodology could be directly and efficiently applied to synthesize key intermediates relevant to pharmaceuticals and a potential drug candidate. For C(sp3)−C(sp2) couplings, radical probe experiments militated in favor of a carbon‐centered radical derived from the electrophile. At the same time, reactions run with a pre‐formed activated boron nucleophile coupled to competition experiments supported the involvement of neutral, rather than an anionic, (hetero)aryl boronic ester in the key transmetalation step. [ABSTRACT FROM AUTHOR]

Photo‐release of triphenylphosphine from a sulfonamide azobenzene ruthenium–arene complex was exploited to activate PdIICl2 into Pd0 catalyst, for the photo‐initiation of Sonogashira cross‐coupling. The transformation was initiated on demand – by using simple white LED strip lights – with a high temporal response and the ability to control reaction rate by changing the irradiation time. Various substrates were successfully applied to this photo‐initiated cross‐coupling, thus illustrating the wide functional‐group tolerance of our photo‐caged catalyst activator, without any need for sophisticated photochemistry apparatus. [ABSTRACT FROM AUTHOR]

The synthesis and solid‐state characterization of an array of well‐defined low‐coordinate C1‐symmetric β‐diketiminatoiron(II) alkyl complexes B3–B6 featuring steric and electronic variations on one of the N‐aryl substituents of the β‐diketiminate ligand scaffold are reported. All complexes display unique catalytic abilities of promoting the selective exo‐cyclohydroamination of unprotected 2,2‐diphenylpent‐4‐en‐1‐amine (1 a) under mild reactions conditions. The incorporation of a potentially coordinative ortho‐methoxy substituent on one of the N‐aryl rings of the β‐diketiminate skeleton, in conjunction with a more crowded 2,6‐diisopropylphenyl group on the other, affords a far more active catalyst (B3) than our previously reported C2‐symmetric β‐diketiminatoiron(II) alkyl complex B (Ar1=Ar2=2,4,6‐(Me)3C6H2)/cyclopentylamine system. Comparative studies let us postulate that this superior activity of B3, when compared with B4‐B6, is likely arising from steric effects and/or the coordinating ability of the ortho‐methoxy substituent. The scope and limitations of this novel C1‐symmetric β‐diketiminatoiron(II) alkyl complex B3 are also presented. [ABSTRACT FROM AUTHOR]

We describe herein the photoredox‐initiated 1,2‐difunctionalization of alkene derivatives with N‐chloro S‐fluoroalkyl sulfoximines yielding novel fluoroalkyl sulfoximine scaffolds. The reaction is proposed to proceed through an atom‐transfer radical addition (ATRA) mechanism involving the generation of fluorinated nitrogen‐centered sulfoximidoyl radicals. [ABSTRACT FROM AUTHOR]

We report herein the preparation of ortho‐vinylaryl S‐trifluoromethylated sulfoximines through cross‐coupling reactions. Two efficient palladium‐catalyzed procedures (Stille and Suzuki) were developed, with use of ortho‐iodo aryl sulfoximines as substrates, to give various vinyl derivatives in good yields. The difference in reactivity of the fluorinated derivatives, compared to nonfluorinated counterparts, allowed the use of free NH sulfoximines in the coupling processes, where they proved to be inert to cyclization. Finally, further transformations have been explored, such as metathesis coupling reactions, after post‐functionalization of the nitrogen atom by another vinyl group. [ABSTRACT FROM AUTHOR]

This short review provides an overview of the most noteworthy achievements in the area of hydroamination and formal hydroamination of unactivated alkenes catalysed by zinc-, copper-, nickel-, cobalt-, and iron-based systems. The relevant literature from 2009 until mid-2016 has been covered. 1 Introduction 2 Activation Strategies 3 Zinc-Based Catalytic Systems 4 Copper-Based Catalytic Systems 5 Nickel-Based Catalytic System 6 Cobalt-Based Catalytic System 7 Iron-Based Catalytic Systems 8 Outlook [ABSTRACT FROM AUTHOR]

The novel class of bis-arylaminoacenaphthylenes (Ar-BIANH2) was employed for the preparation of zirconium and yttrium complexes to be used as catalysts for cyclohydroamination of a number of primary and secondary aminoalkenes. The complex [(2,6-iPr2C6H3-BIAN)Zr(NMe2)2(η1-NHMe2)] was isolated and completely characterized, including X-ray diffraction analysis. Despite its easy and almost quantitative isolation, it showed only moderate catalytic performance in the intramolecular hydroamination, irrespective of the cyclization precursor used. On the other hand, in situ generated YIII complexes obtained using the same class of ligands were found to be very active, leading to the hydroamination of substrates including those normally reluctant in undergoing cyclization such as those featuring an internal non-activated C=C double bond. Electron donating substituents and especially steric hindrance on the ligand improve the performance of the catalysts, allowing us to decrease the catalyst loading to 1 mol% in the latter case. [ABSTRACT FROM AUTHOR]

With the rising interest in asymmetric catalysis promoted by earth-abundant elements, a chiral ligand will undoubtedly be the most valuable unit of the catalyst. The first proof of concept of the use of a multitask chiral ligand in an asymmetric assisted tandem catalysis protocol that successively combines metallo- and organocatalytic processes is reported herein. In this protocol, the chiral ligand of the newly designed rare-earth catalyst of the first reaction is converted into a novel chiral organocatalyst for the second transformation by the simple addition of HCl. The observation of some enantioinduction in the tandem sequence-alkyne hydroamination followed by enantioselective Friedel-Crafts alkylation-confirms the relay of the chiral N, N, N′, N′-tetradentate ligand and the importance of its pyridylmethylamine scaffold. [ABSTRACT FROM AUTHOR]