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The precise control of the regioselectivity in the transition metal‐catalyzed migratory hydrofunctionalization of alkenes remains a big challenge. With a transient ketimine directing group, the nickel‐catalyzed migratory β‐selective hydroarylation and hydroalkenylation of alkenyl ketones has been realized with aryl boronic acids using alkyl halide as the mild hydride source for the first time. The key to this success is the use of a diphosphine ligand, which is capable of the generation of a Ni(II)‐H species in the presence of alkyl bromide, and enabling the efficient migratory insertion of alkene into Ni(II)‐H species and the sequent rapid chain walking process. The present approach diminishes organosilanes reductant, tolerates a wide array of complex functionalities with excellent regioselective control. Moreover, this catalytic system could also be applied to the migratory hydroarylation of alkenyl azahetereoarenes, thus providing a general approach for the preparation of 1,2‐aryl heteroaryl motifs with wide potential applications in pharmaceutical discovery. [ABSTRACT FROM AUTHOR]

Reactions of unactivated alkyl chlorides under mild and sustainable conditions are rare compared to those of alkyl bromides or iodides. As a result, synthetic methods capable of modifying the vast chemical space of chloroalkane reagents, wastes, and materials are limited. We report the cobalt‐catalyzed reductive addition of unactivated alkyl chlorides to conjugated alkenes. Co‐catalyzed activation of alkyl chlorides is performed under electroreductive conditions, and the resulting reactions constitute formal alkyl‐alkyl bond formation. In addition to developing an operationally simple methodology, detailed mechanistic studies provide insights into the elementary steps of a proposed catalytic cycle. In particular, we propose a switch in the mechanism of C−Cl bond activation from nucleophilic substitution to halogen atom abstraction, which is critical for efficiently generating alkyl radicals. These mechanistic insights were leveraged in designing ligands that enable couplings of primary, secondary, and tertiary alkyl chlorides. [ABSTRACT FROM AUTHOR]

Electrochemical approaches to form C(sp2)−C(sp3) bonds have focused on coupling C(sp3) electrophiles that form stabilized carbon‐centered radicals upon reduction or oxidation. Whereas alkyl bromides are desirable C(sp3) coupling partners owing to their availability and cost‐effectiveness, their tendency to undergo radical‐radical homocoupling makes them challenging substrates for electroreductive cross‐coupling. Herein, we disclose a metal‐free regioselective cross‐coupling of 1,4‐dicyanobenzene, a useful precursor to aromatic nitriles, and alkyl bromides. Alkyl bromide reduction is mediated directly by 1,4‐dicyanobenzene radical anions, leading to negligible homocoupling and high cross‐selectivity to form 1,4‐alkyl cyanobenzenes. The cross‐coupling scheme is compatible with oxidatively sensitive and acidic functional groups such as amines and alcohols, which have proven difficult to incorporate in alternative electrochemical approaches using carboxylic acids as C(sp3) precursors. [ABSTRACT FROM AUTHOR]

Aliphatic trifluoromethyl ketones are a type of unique fluorine‐containing subunit which play a significant role in altering the physical and biological properties of molecules. Catalytic methods to provide direct access to aliphatic trifluoromethyl ketones are highly desirable yet remain underdeveloped, partially owing to the high reactivity and instability of trifluoroacetyl radical. Herein, we report a photocatalytic synthesis of trifluoromethyl ketones from alkyl bromides with trifluoroacetic anhydride. The reaction features dual visible‐light and halogen‐atom‐transfer catalysis, followed by an enabling radical‐radical cross‐coupling of an alkyl radical with a stabilized trifluoromethyl radical. The reaction provides straightforward access to aliphatic trifluoromethyl ketones from readily available and cost‐effective alkyl halides and trifluoroacetic anhydride (TFAA). [ABSTRACT FROM AUTHOR]

Activated alkyl halides have been extensively explored to generate alkyl radicals with Ru‐ and Ir‐ photocatalysts for 1,2‐difunctionalization of alkenes, but unactivated alkyl bromides remain challenging substrates due to their strong reduction potential. Here we report a three‐component 1,2‐difunctionalization reaction of alkenes, unactivated alkyl bromides and nucleophiles (e.g. amines and indoles) using a trinuclear gold catalyst [Au3(tppm)2](OTf)3. It can achieve the 1,2‐aminoalkylation and 1,2‐alkylarylation readily. This protocol has a broad reaction scope and excellent functional group compatibility (>100 examples with up to 96 % yield). It also affords a robust formal [2+2+1] cyclization strategy for the concise construction of pyrrolidine skeletons under mild reaction conditions. Mechanistic studies support an inner‐sphere single electron transfer pathway for the successful cleavage of inert C−Br bonds. [ABSTRACT FROM AUTHOR]

The difunctionalization of unsaturated bonds plays a vital role in the enrichment of molecular complexity. While various catalytic methods for alkene and alkyne difunctionalization have been developed in recent years, hetero‐functionalization the introduction of two different atoms has been less explored. This is mainly due to the challenges associated with achieving high chemo‐, regio‐, and stereoselectivity, especially when adding two similar atoms from the same group across unsaturated bonds. In this study, we describe a nickel‐catalyzed, three‐component reductive protocol for group 14 element hetero‐difunctionalization of 1,3‐enynes using electrochemistry. This new method is mild, selective, and general, allowing for the silyl‐, germanyl‐, and stannyl‐alkylation of enynes. Various chlorosilanes as well as chlorogermans, and chlorostannanes can be successfully used in combination with aryl/alkyl‐substituted 1,3‐enynes and primary, secondary, and tertiary alkyl bromides in the electroreductive coupling. [ABSTRACT FROM AUTHOR]

An attractive approach to selective functionalization of remote C−H bonds is a metal/hydride shift/cross‐coupling reaction sequence. Complimentary to the heavily exploited 1,2‐nickel/hydride shift along an sp3 chain, a chain‐walking process, the 1,4‐nickel/hydride shift along an sp2 chain is more complex. Here we report an unprecedented aryl‐to‐vinyl 1,4‐nickel/hydride shift reaction, in which the migratory alkenylnickel species generated in situ is selectively trapped by one of various coupling partners, such as isocyanates, alkyl bromides, aryl chlorides or alkynyl bromides, allowing regio‐ and stereoselective access to trisubstituted alkenes. In contrast to the well‐reported ipso‐aryl coupling reactions, this strategy provides remote alkenyl C−H functionalized products with good yield and with excellent chemo‐, regio‐ and E/Z‐selectivity. [ABSTRACT FROM AUTHOR]

Despite several methodologies established for C(sp2)−I selective C(sp2)−C(sp3) bond formations, achieving arene‐flanked quaternary carbons by cross‐coupling of tertiary alkyl precursors with bromo(iodo)arenes in a C(sp2)−I selective manner is rare. Here we report a general Ni‐catalyzed C(sp2)−I selective cross‐electrophile coupling (XEC) reaction, in which, beyond 3° alkyl bromides (for constructing arene‐flanked quaternary carbons), 2° and 1° alkyl bromides are also demonstrated to be viable coupling partners. Moreover, this mild XEC displays excellent C(sp2)−I selectivity and functional group compatibility. The practicality of this XEC is demonstrated in simplifying the routes to several medicinally relevant and synthetically challenging compounds. Extensive experiments show that the terpyridine‐ligated NiI halide can exclusively activate alkyl bromides, forming a NiI−alkyl complex through a Zn reduction. Attendant density functional theory (DFT) calculations reveal two different pathways for the oxidative addition of the NiI−alkyl complex to the C(sp2)−I bond of bromo(iodo)arenes, explaining both the high C(sp2)−I selectivity and generality of our XEC. [ABSTRACT FROM AUTHOR]

Simultaneous electrochemical ring contraction and expansion reactions remain unexplored to date. Herein, the reductive electrosynthesis of heterocycle‐fused fulleroids from fullerotetrahydropyridazines and electrophiles in the presence of a trace amount of oxygen has been achieved with concurrent ring contraction and ring expansion. When trifluoroacetic acid and alkyl bromides are employed as electrophiles, heterocycle‐fused fulleroids with a 1,1,2,6‐configuration are regioselectively formed. In contrast, heterocycle‐fused fulleroids with a 1,1,4,6‐configuration are regioselectively produced as two separable stereoisomers if phthaloyl chloride is used as the electrophile. The reaction proceeds through multiple steps of electroreduction, heterocycle ring‐opening, oxygen oxidation, heterocycle contraction, fullerene cage expansion, and nucleophilic addition. The structures of these fulleroids have been determined by spectroscopic data and single‐crystal X‐ray diffraction analyses. The observed high regioselectivities have been rationalized by theoretical calculations. Representative fulleroids have been applied in organic solar cells as the third component and exhibit good performance. [ABSTRACT FROM AUTHOR]

Herein, we report a copper‐catalyzed stereospecific fluorination involving CsF and α‐bromocarboxamides as tertiary alkyl sources that, unlike traditional stereospecific routes involving stereoinversive SN2 reactions, proceeds with retention of stereochemistry. The developed stereospecific Cu‐catalyzed reaction is among the most efficient methods for synthesizing fluorinated molecules that possess highly congested stereogenic carbon centers. Mechanistic studies revealed that the combined reactivity of CuF2 and Cs salt is essential for completing the catalytic cycle. Our catalytic system underwent fluorination exclusively with tertiary alkyl bromides and did not react with primary alkyl bromides, indicating that this stereospecific fluorination methodology is suitable for synthesizing fluorinated building blocks possessing stereo‐defined F‐containing tertiary carbon stereogenic center. [ABSTRACT FROM AUTHOR]

Functionalizing specific positions on a saturated alkyl molecule is a key challenge in synthetic chemistry. Herein, a ligand‐controlled regiodivergent alkylations of alkyl bromides at different positions by Ni‐catalyzed alkyl‐alkyl cross‐electrophile coupling with the second alkyl bromides has been developed. The reaction undergoes site‐selective isomerization on one alkyl bromides in a controlled manner, providing switchable access to diverse alkylated structures at different sites of alkyl bromides. The reaction occurs at three similar positions with excellent chemo‐ and regioselectivity, representing a remarkable ligand tuned reactivity between alkyl‐alkyl cross‐coupling and nickel migration along the hydrocarbon side chain. This reaction offers a catalytic platform to diverse saturated architectures by alkyl‐alkyl bond‐formation from identical starting materials. [ABSTRACT FROM AUTHOR]

Herein, we developed a new procedure on 1,2‐dicarbonylative cyclization of 4‐aryl‐1‐butenes with alkyl bromides. Using simple copper catalyst, two molecules of carbon monoxide were introduced into the double bond with the formation of four new C−C bonds and a new ring. Various α‐tetralones and 2,3‐dihydroquinolin‐4‐ones were formed in moderate to good yields. [ABSTRACT FROM AUTHOR]

Transition metal‐catalyzed carbonylative cross‐coupling reactions are some of the most widely used methods in organic synthesis. However, despite the obvious advantages of iron as an abundant and low toxicity transition metal catalyst, its practical application in carbonylation reaction remains largely unexplored. Here we report our recent study on Fe‐catalyzed alkoxycarbonylation of alkyl halides. Mechanistic studies indicate that the reaction is catalyzed by an in situ generated Fe2− complex. This low‐valent iron species activates alkyl bromides via a distinctive two‐electron transfer (TET) process, whereas it proceeds via a single electron transfer (SET) process for alkyl iodides which is consistent with literature. [ABSTRACT FROM AUTHOR]

Catalysis by excited‐state palladium has emerged as an active area of research, but controlling the enantioselectivity remains a challenge. Herein, we report the use of synergistic Pd/Cu catalysis to accomplish the first three‐component photochemical 1,4‐bisalkylation reactions of 1,3‐butadiene. Consequently, α‐amino acid esters bearing quaternary stereocenters were expeditiously synthesized from three simple starting materials: an alkyl bromide, butadiene, and an aldimine ester. Experimental and computational investigation of the reaction mechanism confirmed a radical pathway involving catalysis by an excited‐state palladium species. The stereochemistry is mainly controlled by the chiral Cu catalyst. [ABSTRACT FROM AUTHOR]

Catalytic enantioselective hydroxylation of prochiral dihydrosilanes with water is expected to be a highly efficient way to access Si‐chiral silanols, yet has remained unknown up to date. Herein, we describe a strategy for realizing this reaction: using an alkyl bromide as a single‐electron transfer (SET) oxidant for invoking CuII species and chiral multidentate anionic N,N,P‐ligands for effective enantiocontrol. The reaction readily provides a broad range of Si‐chiral silanols with high enantioselectivity and excellent functional group compatibility. In addition, we manifest the synthetic potential by establishing two synthetic schemes for transforming the obtained products into Si‐chiral compounds with high structural diversity. Our preliminary mechanistic studies support a mechanism involving SET for recruiting chiral CuII species as the active catalyst and its subsequent σ‐metathesis with dihydrosilanes. [ABSTRACT FROM AUTHOR]

A highly regio‐ and diastereoselective nucleophilic substitution at the quaternary carbon stereocenter of cyclopropyl ketones and cyclopropyl carbinol derivatives using TMSBr, DMPSCl and TMSN3 as nucleophiles has been developed. A variety of acyclic tertiary alkyl bromides, chlorides and azides were therefore prepared with excellent diastereopurity. The substitution occurs at the most substituted quaternary carbon center in a stereoinvertive manner, which may be attributed to the existence of a bicyclobutonium species. [ABSTRACT FROM AUTHOR]

Controllable production of α‐keto amides and amides from the same substrates is an attractive goal in the field of transition‐metal‐catalyzed (double‐)carbonylation. Herein, a novel copper‐catalyzed highly selective double carbonylation of alkyl bromides has been developed. Moderate to good yields of α‐keto amides were obtained as the only products. In the case of alkyl iodides, double‐ and mono‐carbonylation can be achieved controllably under different conditions. [ABSTRACT FROM AUTHOR]

Catalytic alkylation of stable alkenyl C−O electrophiles is synthetically appealing, but studies to date have typically focused on the reactions with alkyl Grignard reagents. We report herein a cross‐electrophile reaction of alkenyl acetates with alkyl bromides. This work has enabled a new method for the synthesis of aliphatic alkenes from alkenyl acetates to be established that can be used to add more structural complexity and molecular diversity with enhanced functionality tolerance. The method allows for a gram‐scale reaction and modification of biologically active molecules, and it affords access to useful building blocks. Preliminary mechanistic studies reveal that the NiI species plays an essential role for the success of the coupling of these two reactivity‐mismatched electrophiles. [ABSTRACT FROM AUTHOR]

Monofluorinated alkyl compounds are of great importance in pharmaceuticals, agrochemicals and materials. Herein, we describe a direct nickel‐catalyzed monofluoromethylation of unactivated alkyl halides using a low‐cost industrial raw material, bromofluoromethane, by demonstrating a general and efficient reductive cross‐coupling of two alkyl halides. Results with 1‐bromo‐1‐fluoroalkane also demonstrate the viability of monofluoroalkylation, which further established the first example of reductive C(sp3)‐C(sp3) cross‐coupling fluoroalkylation. These transformations demonstrate high efficiency, mild conditions, and excellent functional‐group compatibility, especially for a range of pharmaceuticals and biologically active compounds. Mechanistic studies support a radical pathway. Kinetic studies reveal that the reaction is first‐order dependent on catalyst and alkyl bromide whereas the generation of monofluoroalkyl radical is not involved in the rate‐determining step. This strategy provides a general and efficient method for the synthesis of aliphatic fluorides. [ABSTRACT FROM AUTHOR]

Newly structured pH‐responsive smart surfactants (N+‐(n)‐N, n=14, 16) from alkyl trimethylammonium bromides are reported. In neutral and alkaline media N+‐(n)‐N behaves as a normal cationic surfactant and stabilizes conventional emulsions alone, as well as Pickering emulsions and oil‐in‐dispersion emulsions together with oppositely and similarly charged nanoparticles, respectively. In acidic media N+‐(n)‐N becomes a hydrophilic Bola‐type surfactant, N+‐(n)‐NH+, and is an inferior emulsifier either when used alone or together with charged nanoparticles, resulting in demulsification. N+‐(n)‐NH+ returns to the aqueous phase alone or together with nanoparticles after demulsification without contaminating the oil phase, and the aqueous phase can be recycled when triggered by pH change. This protocol is a green process and leads to preparation of various temporarily stable emulsions which are often used in emulsion polymerization, heterogeneous catalysis, and oil transportation. [ABSTRACT FROM AUTHOR]

In contrast to the wealth of asymmetric transformations for generating central chirality from alkyl radicals, the enantiocontrol over the allenyl radicals for forging axial chirality represents an uncharted domain. The challenge arises from the unique elongated linear configuration of the allenyl radicals that necessitates the stereo‐differentiation of remote motifs away from the radical reaction site. We herein describe a copper‐catalyzed asymmetric radical 1,4‐carboalkynylation of 1,3‐enynes via the coupling of allenyl radicals with terminal alkynes, providing diverse synthetically challenging tetrasubstituted chiral allenes. A chiral N,N,P‐ligand is crucial for both the reaction initiation and the enantiocontrol over the highly reactive allenyl radicals. The reaction features a broad substrate scope, covering a variety of (hetero)aryl and alkyl alkynes and 1,3‐enynes as well as radical precursors with excellent functional group tolerance. [ABSTRACT FROM AUTHOR]

A catalytic asymmetric alkylation of azoles with secondary 1‐arylalkyl bromides through direct C−H functionalization is reported. Under blue‐light photoexcitation, a copper(I)/carbazole‐based bisoxazoline (CbzBox) catalytic system exhibits good reactivity and high stereoselectivity, thus offering an efficient strategy for the construction of chiral alkyl azoles. These reactions proceed at low temperature and are compatible with a wide range of azoles. [ABSTRACT FROM AUTHOR]

The development of enantioconvergent cross‐coupling of racemic alkyl halides directly with heteroarene C(sp2)−H bonds has been impeded by the use of a base at elevated temperature that leads to racemization. We herein report a copper(I)/cinchona‐alkaloid‐derived N,N,P‐ligand catalytic system that enables oxidative addition with racemic alkyl bromides under mild conditions. Thus, coupling with azole C(sp2)−H bonds has been achieved in high enantioselectivity, affording a number of potentially useful α‐chiral alkylated azoles, such as 1,3,4‐oxadiazoles, oxazoles, and benzo[d]oxazoles as well as 1,3,4‐triazoles, for drug discovery. Mechanistic experiments indicated facile deprotonation of an azole C(sp2)−H bond and the involvement of alkyl radical species under the reaction conditions. [ABSTRACT FROM AUTHOR]

Utilizing pyridine catalysis, we developed a visible‐light‐induced transition‐metal‐free radical borylation reaction of unactivated alkyl bromides that features a broad substrate scope and mild reaction conditions. Mechanistic studies revealed a novel nucleophilic substitution/photoinduced radical formation pathway, which could be utilized to trigger a variety of radical processes. [ABSTRACT FROM AUTHOR]

Alkenes, Difunctionalization, Gold Catalysis, Photoredox Catalysis, Radical In their Research Article (e202305121), Jin Xie and co-workers overcome the inherent redox potential limit of alkyl bromides and achieve 1,2-aminoalkylation and 1,2-alkylarylation of different alkenes by using the inner single electron transfer mechanism of an excited trinuclear gold catalyst. Keywords: Alkenes; Difunctionalization; Gold Catalysis; Photoredox Catalysis; Radical EN Alkenes Difunctionalization Gold Catalysis Photoredox Catalysis Radical 1 1 1 08/17/23 20230821 NES 230821 B Inert alkyl bromides b are rarely used in photoinduced 1,2-difunctionalization of alkenes due to their strong reduction potential and bond dissociation energy. [Extracted from the article]

Reported is an asymmetric reductive dicarbofunctionalization of unactivated alkenes. Under the catalysis of a Ni/BOX system, various aryl bromides, incorporating a pendant olefinic unit, were successfully reacted with an array of primary alkyl bromides in the presence of Zn as a reductant, furnishing a series of benzene‐fused cyclic compounds bearing a quaternary stereocenter in high enantioselectivities. Notably, this reaction avoids the use of pregenerated organometallics and demonstrates high tolerance of sensitive functionalities. The preliminary mechanistic investigations reveal that this Ni‐catalyzed reaction proceeds as a cascade consisting of migratory insertion and cross‐coupling with a nickel(I)‐mediated intramolecular 5‐exo cyclization as the enantiodetermining step. [ABSTRACT FROM AUTHOR]

Visible‐light induced, palladium catalyzed alkylations of α,β‐unsaturated acids with unactivated alkyl bromides are described. A variety of primary, secondary, and tertiary alkyl bromides are activated by the photoexcited palladium metal catalyst to provide a series of olefins at room temperature under mild reaction conditions. Mechanistic investigations and density functional theory (DFT) studies suggest that a photoinduced inner‐sphere mechanism is operative in which a barrierless, single‐electron transfer oxidative addition of the alkyl halide to Pd0 is key for the efficient transformation. [ABSTRACT FROM AUTHOR]

The development of a general, nickel‐catalyzed alkyl‐Mizoroki–Heck reaction of unactivated alkyl bromides is described. The mild reaction proceeds efficiently using a wide range of primary and secondary alkyl bromides, and examples of intermolecular cross‐couplings are provided. Reaction alkene regioselectivity is significantly enhanced over prior carbocyclizations using palladium catalysis. Mechanistic investigations are consistent with a direct carbocyclization in contrast to the auto‐tandem atom‐transfer cyclization and halide elimination previously observed with palladium catalysis. [ABSTRACT FROM AUTHOR]

Abstract: A mild and practical Barbier–Negishi coupling of secondary alkyl bromides with aryl and alkenyl triflates and nonaflates has been developed. This challenging reaction was enabled by the use of a very bulky imidazole‐based phosphine ligand, which resulted in good yields as well as good chemo‐ and site selectivities for a broad range of substrates at room temperature and under non‐aqueous conditions. This reaction was extended to primary alkyl bromides by using an analogous pyrazole‐based ligand. [ABSTRACT FROM AUTHOR]

Reported herein is a novel visible-light photoredox system with Pd(PPh3)4 as the sole catalyst for the realization of the first direct cross-coupling of C(sp3)−H bonds in N-aryl tetrahydroisoquinolines with unactivated alkyl bromides. Moreover, intra- and intermolecular alkylations of heteroarenes were also developed under mild reaction conditions. A variety of tertiary, secondary, and primary alkyl bromides undergo reaction to generate C(sp3)−C(sp3) and C(sp2)−C(sp3) bonds in moderate to excellent yields. These redox-neutral reactions feature broad substrate scope (>60 examples), good functional-group tolerance, and facile generation of quaternary centers. Mechanistic studies indicate that the simple palladium complex acts as the visible-light photocatalyst and radicals are involved in the process. [ABSTRACT FROM AUTHOR]

We have developed a catalytic method for the hydroalkylation of allenes using alkyl triflates as electrophiles and silane as a hydride source. The reaction has an excellent substrate scope and is compatible with a wide range of functional groups, including esters, aryl halides, aryl boronic esters, sulfonamides, alkyl tosylates, and alkyl bromides. We found evidence for a reaction mechanism that involves unusual dinuclear copper ally complexes as catalytic intermediates. The unusual structure of these complexes provides a rationale for their unexpected reactivity. [ABSTRACT FROM AUTHOR]

Milstein's complex, (PNN)RuHCl(CO), catalyzes the efficient reduction of aryl and alkyl halides under relatively mild conditions by using propan-2-ol and a base. Sterically hindered tertiary and neopentyl substrates are reduced efficiently, as well as more functionalized aryl and alkyl bromides. The reduction process is proposed to occur by radical abstraction/hydrodehalogenation steps at ruthenium. Our research represents a safer and more sustainable alternative to typical silane, lithium aluminium hydride, and tin-based conditions for these reductions. [ABSTRACT FROM AUTHOR]

Hydrocarbons are still the most important precursors of functionalized organic molecules, which has stirred interest in the discovery of new C−H bond functionalization methods. We describe herein a new step-economical approach that enables C−C bonds to be constructed at the terminal position of linear alkanes. First, we show that secondary alkyl bromides can undergo in situ conversion into alkyl zinc bromides and regioconvergent Negishi coupling with aryl or alkenyl triflates. The use of a suitable phosphine ligand favoring Pd migration enabled the selective formation of the linear cross-coupling product. Subsequently, mixtures of secondary alkyl bromides were prepared from linear alkanes by standard bromination, and regioconvergent cross-coupling then provided access to the corresponding linear arylation product in only two steps. [ABSTRACT FROM AUTHOR]

A user-friendly, nickel-catalyzed reductive amidation of unactivated primary, secondary, and tertiary alkyl bromides with isocyanates is described. This catalytic strategy offers an efficient synthesis of a wide range of aliphatic amides under mild conditions and with an excellent chemoselectivity profile while avoiding the use of stoichiometric and sensitive organometallic reagents. [ABSTRACT FROM AUTHOR]

A new iron-facilitated silver-mediated radical 1,2-alkylarylation of styrenes with α-carbonyl alkyl bromides and indoles is described, and two new C−C bonds were generated in a single step through a sequence of intermolecular C(sp3)−Br functionalization and C(sp2)−H functionalization across the alkenes. This method provides an efficient access to alkylated indoles with broad substrate scope and excellent selectivity. [ABSTRACT FROM AUTHOR]

Although the advances on carbon halide reductive elimination have been made, the alkyl bromide and chloride analogues remain a challenge. Here, a palladium(0)-catalyzed iminohalogenation of γ,δ-unsaturated oxime esters is described, and the use of electron-poor phosphine ligands proved to be crucial to promoting alkyl bromide and chloride reductive elimination. Furthermore, SN2-type alkyl bromide and chloride reductive elimination has also been established. [ABSTRACT FROM AUTHOR]

Aktiviert durch Nickel: Die Titelreaktion ist ein neuer und praktischen Ansatz, um terminale Alkine durch Umsetzung mit nichtaktivierten sekundären Alkyliodiden und ‐ bromiden in substituierte Alkine zu überführen (siehe Schema; cod=Cyclo ‐ 1,5 ‐ octadien). [ABSTRACT FROM AUTHOR]