The cover picture shows the copper‐catalyzed Ullmann‐Ma reaction of aryl halides with nucleophiles by the assistance of two‐generation ligands, amino acids and oxalic diamides or related amides. Ullmann‐Ma reaction is one of the most important transformations for the construction of aryl carbon‐carbon and carbon‐heteroatom bonds in organic chemistry. For the details about the history, development, scope and applications of Ullmann‐Ma reaction, please see the article by Cai et al. on page 879–893.
Metal‐catalyzed cross‐coupling reactions belong to the most important transformations in organic synthesis. Copper catalysis has received great attention owing to the low toxicity and low cost of copper. However, traditional Ullmann‐type couplings suffer from limited substrate scopes and harsh reaction conditions. The introduction of several bidentate ligands, such as amino acids, diamines, 1,3‐diketones, and oxalic diamides, over the past two decades has totally changed this situation as these ligands enable the copper‐catalyzed coupling of aryl halides and nucleophiles at both low reaction temperatures and catalyst loadings. The reaction scope has also been greatly expanded, rendering this copper‐based cross‐coupling attractive for both academia and industry. In this Review, we have summarized the latest progress in the development of useful reaction conditions for the coupling of (hetero)aryl halides with different nucleophiles. Additionally, recent advances in copper‐catalyzed coupling reactions with aryl boronates and the copper‐based trifluoromethylation of aromatic electrophiles will be discussed. 相似文献
Copper‐catalyzed Ullmann condensations are key reactions for the formation of carbon–heteroatom and carbon–carbon bonds in organic synthesis. These reactions can lead to structural moieties that are prevalent in building blocks of active molecules in the life sciences and in many material precursors. An increasing number of publications have appeared concerning Ullmann‐type intermolecular reactions for the coupling of aryl and vinyl halides with N, O, and C nucleophiles, and this Minireview highlights recent and major developments in this topic since 2004. 相似文献
In Pd‐catalyzed C? N cross‐coupling reactions, α‐branched secondary amines are difficult coupling partners and the desired products are often produced in low yields. In order to provide a robust method for accessing N‐aryl α‐branched tertiary amines, new catalysts have been designed to suppress undesired side reactions often encountered when these amine nucleophiles are used. These advances enabled the arylation of a wide array of sterically encumbered amines, highlighting the importance of rational ligand design in facilitating challenging Pd‐catalyzed cross‐coupling reactions. 相似文献
Synthesis of di‐substituted aryl olefins via a Pd(0)‐catalyzed cross‐coupling reaction of biphenyl ketones/aldehydes, tosylhydrazide, and aryl bromides (or benzyl halides) was developed. This methodology was achieved by one‐pot two‐step reactions involving the preparation of N ‐tosylhydrazones by reacting tosylhydrazide with biphenyl ketones/aldehydes, followed by coupling with aryl bromides (or benzyl halides) in the presence of Pd(PPh3 )4 and lithium t ‐butoxide to produce various di‐substituted aryl olefins in moderate to good yields. 相似文献
A combination of nickel and photoredox catalysts promoted novel cross‐coupling reactions of aryl halides with 4‐alkyl‐1,4‐dihydropyridines. 4‐Alkyl‐1,4‐dihydropyridines act as formal nucleophilic alkylation reagents through a photoredox‐catalyzed carbon–carbon (C?C) bond‐cleavage process. The present strategy provides an alternative to classical carbon‐centered nucleophiles, such as organometallic reagents. 相似文献
A combinatorial nickel‐catalyzed monofluoroalkylation of aryl halides with unactivated fluoroalkyl halides by reductive cross‐coupling has been developed. This method demonstrated high efficiency, mild conditions, and excellent functional‐group tolerance, thus enabling the late‐stage monofluoroalkylation of diverse drugs. The key to success was the combination of diverse readily available bidentate and monodentate pyridine‐type nitrogen ligands with nickel, which in situ generated a variety of readily tunable catalysts to promote fluoroalkylation with broad scope with respect to both coupling partners. This combinatorial catalysis strategy offers a solution for nickel‐catalyzed reductive cross‐coupling reactions and provides an efficient way to synthesize fluoroalkylated druglike molecules for drug discovery. 相似文献
Sulfur‐containing molecules such as thioethers are commonly found in chemical biology, organic synthesis, and materials chemistry. While many reliable methods have been developed for preparing these compounds, harsh reaction conditions are usually required in the traditional methods. The transition metals have been applied in this field, and the palladium‐catalyzed coupling of thiols with aryl halides and pseudo halides is one of the most important methods in the synthesis of thioethers. Other metals have also been used for the same purpose. Here, we summarize recent efforts in metal‐catalyzed C? S bond cross‐coupling reactions, focusing especially on the coupling of thiols with aryl‐ and vinyl halides based on different metals. 相似文献
Decarboxylative cross‐coupling reactions of substituted 2‐carboxyazine N‐oxides, with a variety of (hetero)aryl halides, by bimetallic Pd0/CuI and Pd0/AgI catalysis are reported. Two possible pathways, a conventional bimetallic‐catalyzed decarboxylative arylation, as well as a protodecarboxylative/direct C?H arylation sequence have been considered. These methods provide the first general decarboxylative arylation methodology for the 2‐carboxyazine series. 相似文献
The reaction scope of iron‐ and cobalt‐catalyzed cross‐coupling reactions in the presence of isoquinoline (quinoline) in the solvent mixture tBuOMe/THF has been further investigated. Various 2‐halogenated pyridine, pyrimidine, and triazine derivatives were arylated under these mild conditions in excellent yields. The presence of isoquinoline allows us to perform Fe‐catalyzed cross‐coupling reactions between 6‐chloroquinoline and aryl magnesium reagents. Furthermore, it was found that the use of 10 % N,N‐dimethylquinoline‐8‐amine increases the yields of some Co‐catalyzed cross‐coupling reactions with chloropyridines bearing electron‐withdrawing substituents. 相似文献
Bulky P,P?O ligands were designed to inhibit isomerization and reduction side reactions during the cross coupling between sterically hindered aryl halides and alkylboronic acids. Suzuki–Miyaura cross‐couplings between di‐ortho‐substituted aryl bromides and acyclic secondary alkylboronic acids have been achieved with high yields. The method has also enabled the preparation of ortho‐alkoxy di‐ortho‐substituted arenes bearing isopropyl groups in excellent yields. The utility of the synthetic method has been demonstrated in a late‐stage modification of estrone and in the application to a new synthetic route toward gossypol. 相似文献
The stereoselective synthesis of trisubstituted alkenes is challenging. Here, we show that an iron‐catalyzed anti‐selective carbozincation of terminal alkynes can be combined with a base‐metal‐catalyzed cross‐coupling to prepare trisubstituted alkenes in a one‐pot reaction and with high regio‐ and stereocontrol. Cu‐, Ni‐, and Co‐based catalytic systems are developed for the coupling of sp‐, sp2‐, and sp3‐hybridized carbon electrophiles, respectively. The method encompasses a large substrate scope, as various alkynyl, aryl, alkenyl, acyl, and alkyl halides are suitable coupling partners. Compared with conventional carbometalation reactions of alkynes, the current method avoids pre‐made organometallic reagents and has a distinct stereoselectivity. 相似文献
A catalytic amount of cesium carbonate (10 mol%) was found to be capable of effectively catalyzing the insertion of indium powder into alkyl iodides. The thus‐generated alkyl indium reagents could readily undergo palladium‐catalyzed cross‐coupling reactions with a wide variety of aryl halides, showing compatibility to a range of important functional groups. 相似文献
Over the past two decades, considerable attention has been given to the development of new ligands for the palladium‐catalyzed arylation of amines and related NH‐containing substrates (i.e., Buchwald–Hartwig amination). The generation of structurally diverse ligands, by research groups in both academia and industry, has facilitated the accommodation of sterically and electronically divergent substrates including ammonia, hydrazine, amines, amides, and NH heterocycles. Despite these achievements, problems with catalyst generality persist and access to multiple ligands is necessary to accommodate all of these NH‐containing substrates. In our quest to address this significant limitation we identified the BippyPhos/[Pd(cinnamyl)Cl]2 catalyst system as being capable of catalyzing the amination of a variety of functionalized (hetero)aryl chlorides, as well as bromides and tosylates, at moderate to low catalyst loadings. The successful transformations described herein include primary and secondary amines, NH heterocycles, amides, ammonia and hydrazine, thus demonstrating the largest scope in the NH‐containing coupling partner reported for a single Pd/ligand catalyst system. We also established BippyPhos/[Pd(cinnamyl)Cl]2 as exhibiting the broadest demonstrated substrate scope for metal‐catalyzed cross‐coupling of (hetero)aryl chlorides with NH indoles. Furthermore, the remarkable ability of BippyPhos/[Pd(cinnamyl)Cl]2 to catalyze both the selective monoarylation of ammonia and the N‐arylation of indoles was exploited in the development of a new one‐pot, two‐step synthesis of N‐aryl heterocycles from ammonia, ortho‐alkynylhalo(hetero)arenes and (hetero) aryl halides through tandem N‐arylation/hydroamination reactions. Although the scope in the NH‐containing coupling partner is broad, BippyPhos/[Pd(cinnamyl)Cl]2 also displays a marked selectivity profile that was exploited in the chemoselective monoarylation of substrates featuring two chemically distinct NH‐containing moieties. 相似文献