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This article explores the challenges and strategies involved in selectively adding carbon-based units to nonactivated alkenes. The authors focus on the use of directing groups, specifically a quinolinamide directing group, in a nickel-catalyzed reaction. This method allows for the efficient synthesis of branched molecules and demonstrates a high level of selectivity. The authors provide experimental results and optimization of reaction conditions to support their findings. Additionally, the article discusses the broad functional-group tolerance of the reaction and its potential applications in pharmaceutical modifications and large-scale reactions. [Extracted from the article]

This article discusses the use of aromatic amine catalysts in a specific chemical reaction. The researchers conducted experiments using different catalysts and found that aryl amines were more effective than alkyl amines. They also discovered that a commercially available proton sponge showed promise as a catalyst. The article explores the catalytic activity of a specific catalyst called cat14 and compares it to other catalysts. While cat14 showed promising results, the study concludes that another scaffold called phenotellurazine performed better in the reactions. Further research is being done to improve the phenotellurazine scaffold and other catalysts. [Extracted from the article]

This article discusses recent developments in the photocatalytic reduction of nitro compounds to valuable intermediates, such as amines and azo compounds. Nitro compounds are widely used in various industries but pose environmental and health hazards due to their toxicity and nondegradability. Traditional reduction methods often use harsh conditions and toxic chemicals, making the utilization of photocatalytic organic transformations an attractive option for sustainable and green chemical processes. The article provides an overview of different photocatalytic systems, including metal-organic frameworks, semiconductors, and nanocomposites, and explores their synthesis, performance, stability, recyclability, and selectivity. The use of hole scavengers and sacrificial reagents to enhance the reduction process is also mentioned. The studies demonstrate the potential of these photocatalytic systems for efficient and environmentally friendly nitro compound reduction. [Extracted from the article]

Moreover, 2-aminobenzoic acids having electron-delocalization substituents, such as phenyl, acetyl, carbamate, and urea gave no yield of the corresponding products (entries 5-7). [35][36][37] We found that the nucleophilicity of nitrogen of 2-(benzylamino)benzoic acids was crucial to result in good yields of products from 2-(benzylamino)benzoic acids bearing electron-donating substituents on benzene ring. Keywords: quinazolinediones; cylic ureas; organocatalysis; intramolecular C-N amide bond formation; Tiemann rearrangement EN quinazolinediones cylic ureas organocatalysis intramolecular C-N amide bond formation Tiemann rearrangement 2052 2058 7 10/09/23 20231024 NES 231024 Graph Quinazolinediones are one of the most important nitrogen-containing heterocyclic compounds due to their common occurrence in natural products. Another key factor of the reaction was the electrophilicity of -chloroaldoxime I O i -methanesulfonates resulting in good yields with electron-withdrawing substituents and moderate yields from aliphatic -chloroaldoxime I O i -methanesulfonates. [Extracted from the article]

It should be mentioned that so far electrocarboxylation has been mainly explored for the carboxylation of olefins and imines, and only a few reports have been published on direct electrocatalytic C(sp SP 3 sp )-H bond carboxylation reactions. In previous studies, transition-metal or transition-metal-free methodologies proceeded through C(sp SP 3 sp )-H bond carboxylation reactions via enolate chemistry to trap a CO SB 2 sb molecule in order to give carboxylation products. Recent Advances on the Carboxylations of C(sp3)-H Bonds Using CO2 as the Carbon Source Keywords: carbon dioxide; transition-metal; transition-metal-free; thermochemical strategy; visible-light-induced photocatalysis; electrocatalysis; reductive C-H carboxylations; carboxylic acids EN carbon dioxide transition-metal transition-metal-free thermochemical strategy visible-light-induced photocatalysis electrocatalysis reductive C-H carboxylations carboxylic acids 1327 1342 16 07/11/23 20230725 NES 230725 Graph 1 Introduction The carboxylic acid unit is omnipresent in bioactive drug molecules, pharmaceuticals, natural products, and agrochemicals. [Extracted from the article]

New methods for the synthesis of 1,3-diaryltriazenes and azo dyes from aryl amines are reported. Both methods involve the formation of aryl diazonium intermediates via the transnitrosation of aryl amines with N -nitrososulfonamides. Each two-step transformation may be performed in one reaction vessel at room temperature with no precautions taken to exclude air or moisture. Several triazene and azo dye structures are reported here for the first time, demonstrating the utility of operating the two-step reaction sequence under mild conditions. [ABSTRACT FROM AUTHOR]

An account of our development of reactions to construct N -heterocycles by triggering cyclization–migration tandem reactions from aryl azides, nitroarenes, and aryl amines is described. The reactivity patterns of metal N -aryl nitrenes, nitrosoarenes, N -aryl nitrogen radical anions, and N -aryl nitrenoids are compared. 1 Introduction 2 Unlocking the Reactivity Embedded in Aryl Azides 3 Exploiting the Reactivity of Nitrosoarenes Generated from Nitroarenes 4 Radical Anion N -Aryl Nitrogen Reactive Intermediates from Nitroarenes 5 Oxidation of Aryl Amines to Access Electrophilic N -Aryl Nitrenoids 6 Conclusion [ABSTRACT FROM AUTHOR]

Herein, we describe the synthesis of a wide variety of imines through oxidative coupling of alcohols and aromatic amines catalyzed by Mn complexes bearing N^N triazole ligands. A wide variety of imines in excellent yields (up to 99%) have been prepared. Mn-based catalysts proved to be highly efficient and versatile, allowing for the first time the preparation of several imines containing N-based heterocycles. [ABSTRACT FROM AUTHOR]

A bimetallic catalytic combination of Mn(OAc)2 and Cu(OAc)2 was found to be significantly effective for the Buchwald-type C–N cross-coupling of aryl chlorides and amines. The reaction was markedly affected by the presence of a poly(amidoamine) dendrimer as a promoter that also possesses the advantages of being stable, nontoxic, biocompatible, nonimmunogenic, and acting as a soluble support for the transition-metal complex. Although, manganese is cheap and environmentally benign, it has not been fully exploited, due to its low intrinsic catalytic activity. Here, the catalytic potential of manganese was drastically increased by the presence of another metal salt, Cu(OAc)2. In the bimetallic composition, Mn significantly influenced the activity and selectivity, and played a vital role in catalysis. We have developed a novel, green, and economical procedure for Buchwald-type C–N cross-coupling of aryl chlorides and amines. This coupling method works under aerobic and solvent-free conditions and gives excellent yields of value-added N-arylated or N-alkylated products. [ABSTRACT FROM AUTHOR]

The use of tertiary amines as surrogates for secondary amines has prominent advantages in terms of stabilization and ease of handling. A Ni-catalyzed transamidation of N -acylsaccharins with tertiary aromatic amines is reported. By using tert -butyl hydroperoxide as the terminal oxidant, this reaction permits selective cleavage of the C(sp3)–N bonds of unsymmetrical tertiary aromatic amines depending on the sizes of the alkyl substituents. [ABSTRACT FROM AUTHOR]

An efficient Cu-catalyzed synthesis of carbazole derivatives is reported, which proceeds by double C–N coupling reactions of 2,2′-dibromobiphenyl and amines in the presence of air. The reaction is robust, proceeds in high yields, and tolerates a series of amines including neutral, electron-rich, electron-deficient aromatic amines and aliphatic amines. [ABSTRACT FROM AUTHOR]

Herein we report the use of a soluble polymer support PEG-2000 on Pd-catalyzed reactions to improve the functionalization of aromatic amines and the synthesis of N-heterocycles. Compatibility of metal-catalyzed reactions for assembling privileged structures such as functionalized anilines were studied. PEG-supported anilines were found to be suitable substrates for Pd-catalyzed N-arylation, Sonogashira and Heck reactions. PEGylated substrates were prepared in yields up to 94%. This work consists on a proof of concept on the use of PEGylated anilines on Pd-catalyzed cross-coupling reactions. Indole core was attained in 82% and 62% yields, via two different routes. [ABSTRACT FROM AUTHOR]

Phenols are considered as an ideal alternative to aryl halides as coupling partners in cross-coupling reactions. In the present work a copper-catalyzed cross-coupling of phenols with various aromatic and aliphatic amines for the synthesis of secondary aryl amines using dichloroimidazolidinedione (DCID) as a new and efficient activating agent has been developed. Substituted phenols were compatible with the standard reaction conditions. The two proposed mechanisms, which are based on the oxidation addition of copper with Ar-OMCID (MCID: Monochloroimidazolidinedione), are also discussed. [ABSTRACT FROM AUTHOR]

A novel lanthanum triflate mediated conversion of N -benzyl-oxycarbonyl-, N -allyloxycarbonyl-, and N -trichloroethoxycarbonyl--protected amines into nonsymmetric ureas was discovered. In this study, lanthanum triflate was found to be an effective catalyst for preparing various nonsymmetric ureas from protected amines. A variety of protected aromatic and aliphatic carbamates reacted readily with various amines in the presence of lanthanum triflate to generate the desired ureas in high yields. This result demonstrated that this novel lanthanum triflate catalyzed preparation of ureas from Cbz, Alloc, and Troc carbamates can be employed for the formation of various urea structures. [ABSTRACT FROM AUTHOR]

A green H2 O-promoted solvent-free hydroamination of electron-deficient terminal alkynes with amines has been developed. All secondary amines, including aliphatic and aromatic amines, gave the corresponding (E)-enamines in good to excellent yields, whereas primary aromatic amines afforded Z -configured products in moderate yields. Propiolates, propyn-1-ones, propynamides, and 1-(ethynylsulfonyl)-4-methylbenzene were explored in this Michael addition. [ABSTRACT FROM AUTHOR]

An efficient and metal-free coupling reaction has been developed that affords acetamides from the corresponding aryl amines and acetonitrile. This method tolerates a wide range of functional groups and is selective toward aryl amines. Preliminary mechanistic studies were conducted. [ABSTRACT FROM AUTHOR]

Herein, we report the natural ligand quebrachitol (QCT) as a promoter for a Cu(II) catalyst, which is highly effective for N-arylation of various amines and related aryl halides. A series of diarylamine derivatives were obtained in high yields by using diethylene glycol (DEG) as both ligand and solvent. The C–N coupling reactions proceed under mild conditions and exhibit good functional group tolerance. [ABSTRACT FROM AUTHOR]

Asymmetric allylic amination of Morita–Baylis–Hillman (MBH) adducts with simple aromatic amines is successfully realized by nucleophilic amine catalysis. A range of substituted α-methylene-β-arylamino esters is accessed in moderate to high yields (up to 88%) and with excellent enantioselectivities (up to 97% ee). Inorganic fluorides are found to be able to improve the enantioselectivity of the allylic amination reaction. A pyrrole-2-carboxylate and a cyclic imide are also compatible with this catalytic system. A chiral 2,3-dihydroquinolin-4-one derivative is easily obtained from the allylic amination product. [ABSTRACT FROM AUTHOR]

We developed an environmentally friendly iridium-catalyzed direct cyclization of aromatic amines with diols that generates the corresponding N-heterocyclic compounds with water as the sole by-product. Thus, under conditions of 165 °C for 18 hours, the direct cyclization of N-methylanilines with 1,3-propanediol by using an IrCl3 catalyst with rac-BINAP as a ligand in mesitylene afforded the corresponding tetrahydroquinoline derivatives with yields ranging from 73 to 83%. Under similar reaction conditions, direct cyclization of anilines with 1,3-propanediol produced the corresponding tetrahydrobenzoquinolizine derivatives with yields ranging from 26 to 76%. [ABSTRACT FROM AUTHOR]

Iodonium ylides can undergo cyclization with a simple tertiary arylamine to afford N-heterocyclic products in a transition-metalfree approach in the absence of an additional initiator/oxidant. The inherent reactivity uncovered in this transformation is fundamentally different from known chemical properties of iodonium ylide compounds, thus providing a new opportunity for the further exploration of iodonium ylide-based chemical transformations. This Synpacts article describes the historical background of iodonium ylide chemistry and highlights recent progress disclosed by our work. 1 Introduction 2 The Strategy for New Reaction Discovery 3 Application to Cyclization of Tertiary Arylamines 4 Conclusion and Perspectives. [ABSTRACT FROM AUTHOR]

A high-yielding cyclocondensation of 4-hydroxycoumarin, phenylglyoxal monohydrate, and heteroarylamines proceeds without catalysis, which gives novel functionalized furo[3,2-c]coumarins and heteroarylamino alkylation of coumarin products in acetonitrile under reflux, is reported for the first time. This tandem process involves sequentially an aldol condensation, Michael addition, a ring closure, and dehydration reaction. [ABSTRACT FROM AUTHOR]

An efficient synthesis of a series of novel symmetrical N-aryl-C-phosphonoacetamidines through reaction of diisopropyl (chloroethynyl)phosphonate with primary aryl amines was developed. This procedure tolerates a wide range of functional groups and has a good atom economy. The (E)-isomer was the major product that crystallized preferentially over the (Z)-isomer. [ABSTRACT FROM AUTHOR]

Primary aromatic amines were synthesized from the corresponding nitrobenzenes via photoinduced reduction. The reaction was found to be effective when nitrobenzenes with electron-withdrawing substituents were irradiated with a broad band of UV light centered at 306 nm. When reactions are completed, products could be isolated by acid-base extraction or by column chromatography. This presenting photoreaction procedure for the synthesis of primary aromatic amines from the corresponding nitrobenzenes proceeds without the need of a sensitizer in isopropanol or THF. Without the usage of catalysts, or stoichiometric reducing reagent containing heavy metals, this photoinduced reduction of nitrobenzenes fulfils the concept of green chemistry. [ABSTRACT FROM AUTHOR]

We demonstrated that a cobalt(II)-TBHP (tert-butyl hydroperoxide) oxidizing system efficiently catalyzes the coupling of aromatic tertiary amines with enol silyl ethers, producing the corresponding &$946;-aminoketones. [ABSTRACT FROM AUTHOR]

Solvent-free reaction of various anilines with á-hydroxy ketones catalyzed by SnCl2·2H2O provides á-amino ketones in excellent yields. While a similar reaction with aliphatic amines is applicable for the synthesis of substituted pyrazines, SnCl2·2H2O permits versatility in the solvent-free reaction of á-hydroxy ketones with ammonium acetate to give the corresponding substituted pyrazines in good to excellent yields. [ABSTRACT FROM AUTHOR]

We report herein the synthesis of 5-(substituted)quinolino[3,4-b]quinoxalin-6(5H)-one derivatives from ethyl 3-(2-bromophenyl)quinoxaline-2-carboxylate under one-pot Buchwald-Hartwig coupling-lactamization reaction. [ABSTRACT FROM AUTHOR]

Cyclizing radical carboaminoxylation of various aryl amines is presented. The aryl diazonium salts in situ generated from the corresponding aryl amines are reduced by tetra-n-butylammonium iodide (TBAI) to give the corresponding aryl radicals. These aryl radicals undergo 5-exo and 6-exo cyclization. Subsequent trapping with TEMPO or various other nitroxides provides the corresponding cyclized carboaminoxylated products in moderate to very good yields. [ABSTRACT FROM AUTHOR]

A procedure for the formation of aryl amides through the palladium-catalyzed coupling of nitriles and aryl bromides, via the formation of intermediary silanoate derived imidate species is reported. Optimization was undertaken and examples of the process are described that furnish the products in up to 86% isolated yield. [ABSTRACT FROM AUTHOR]

An efficient method to radiolabel symmetrical [11C]ureas using 1,8-diazabicycloundec-7-ene (DBU) and cyclotron-produced [11C]CO2 has been developed. [11C]urea derivatives were obtained when aliphatic and aromatic amines were used with excellent radiochemical yields (RCYs) of over 70%. The mechanism of the reaction is proposed on the basis of control experiments. This simple and robust methodology provides a powerful tool to prepare 11C-labelled ureas previously inaccessible by existing methods and enable their utilisation for in vivo molecular imaging applications. [ABSTRACT FROM AUTHOR]

3-Arylamino-1-ferrocenylpropan-1-ones, prepared through aza-Michael addition of aromatic amines to 1-ferrocenylpropenone, were transformed into the corresponding 1,3-amino alcohols upon NaBH4-mediated carbonyl reduction. The latter amino alcohols were deployed as eligible substrates for the synthesis of a variety of ferrocene- containing heterocycles including 1,3-oxazinanes, 1,3-oxazinan- 2-ones, and tetrahydropyrimidin-2-ones, which were subsequently evaluated for their antimicrobial and cytotoxic activities. [ABSTRACT FROM AUTHOR]

A simple and highly atom-economical method for the direct N-alkylation of aromatic amines by using a microflow reactor was developed to overcome the problem of over-alkylation. In the developed method, high-yield conversion (up to 100%) was achieved in a relatively short reaction time. The ratio of mono- to di-benzylated products (3.57:1) was higher than that achieved with batch reactions conducted in a 1 L scale flask (0.87:1). The structural features of the microflow reactor meant that short-chain alkyl halides could be converted into products with high reactivity and selectivity under superheating conditions, although their boiling point was much lower than the reaction temperature. This method was successfully applied to the synthesis of a range of secondary amines including an intermediate of indobufen synthesis. [ABSTRACT FROM AUTHOR]

A two-step, diversity-oriented synthesis of highly functionalized benzofuran-2-carboxamides has been developed. The Ugi four-component reaction of aromatic amines, isocyanides, 2- bromobenzaldehyde, and 2-bromoacetic acid was used to provide a collection of N-aryl 2-bromoacetamides. The latter were then reacted with selected salicyladehydes in the presence of Cs2CO3 in acetonitrile under controlled microwave heating at 90-140°C for 15- 40 minutes to furnish the benzofuran-2-carboxamides in moderate to good yields. [ABSTRACT FROM AUTHOR]

1-Aryl-1,2,3-benzotriazole systems are synthesized in the high-yielding cyclocondensation of 2-(arylamino)aryliminophosphoranes under mild conditions. The reaction concludes the three-step, halogen-free synthetic route starting from simple nitroarenes and arylamines. [ABSTRACT FROM AUTHOR]

Halomonochloride compounds (ClCl, BrCl, ICl) generated in situ from N-halosuccinimide and catalytic chlorotrimethylsilane (TMSCl, 0.1 equiv) can efficiently halogenate aromatic compounds to give halogenated products in good to excellent yields and selectivities. The reaction can be carried out at room temperature or at lower temperatures, requires only one hour, is practical to apply to a wide range of substrates, and provides a simple access to a variety of haloarene compounds. [ABSTRACT FROM AUTHOR]

A Sandmeyer borylation of arylamines via a SN2Ar pathway promoted by methanol with sodium nitrite and hydrochloric acid as diazotization agent has been developed, which provide a simple and green synthetic method to arylboronic acids and arylboronates. [ABSTRACT FROM AUTHOR]

A variety of aromatic amines have been found to expediently undergo copper-catalyzed N-tert-butylation in the presence of tert-butyl 2,2,2-trichloroactimidate at room temperature. [ABSTRACT FROM AUTHOR]

A large variety of halogenated nitroarenes have been selectively reduced with hydrazine hydrate in the presence of Pd/C to give the corresponding (halogenated) anilines in good yield. [ABSTRACT FROM AUTHOR]

Phenylphosphonic acid is an efficient, friendly and reusable heterogeneous catalyst for the synthesis of α-aminophosphonates through a 'one-pot' three-component reaction of amines, carbonyl compounds and dialkyl phosphites under solvent-free conditions. This methodology illustrates a very simple procedure, with wide applicability, extending the scope to aliphatic and aromatic amines, aliphatic and aromatic aldehydes and aliphatic ketones. It also enabled the synthesis of α-aminophosphonates in large scale, clean conversion, easy workup and purification. Excellent results were obtained in each case obtaining the desire compounds in moderate to good yields. [ABSTRACT FROM AUTHOR]

A series of 4-arylamino-8-(alkyl or aryl)hydrazidepyrimido[ 5,4-d]pyrimidines was obtained efficiently from 6-carbo-hydrazonamidepurines by reaction with piperidine. The 6-carbo-hydrazonamidepurines were generated selectively by the reaction of 6-imidatopurine with hydrazides under acidic conditions. [ABSTRACT FROM AUTHOR]

A variety of substituted aromatic systems are synthesized by the Catellani reaction. These are used as precursors for novel amino acids with a basic side chain. [ABSTRACT FROM AUTHOR]

An environmentally benign method was developed for the three-component, one-pot synthesis of 2-nitroamines by heating a solution of an aldehyde, an aromatic amine, and a nitroalkane in 20% water-methanol at 60 °C for five hours in the absence of a catalyst. [ABSTRACT FROM AUTHOR]

Strategies for the one-pot formation of secondary aryl amines from the corresponding nitro aryls by utilizing reductive amination procedures are discussed. The extension of this chemistry where a Suzuki-Miyaura cross-coupling is conducted between a boronic acid and bromonitrobenzene prior to the reductive amination in one-pot is also presented. [ABSTRACT FROM AUTHOR]

Herein we describe an efficient and generally applicable method of protecting a diverse series of aromatic amines with the 'benzostabase' group. We also demonstrate its efficient use in aromatic anionic chemistry including its utility in the anionic ortho Snieckus-Fries rearrangement [ABSTRACT FROM AUTHOR]

A direct C(sp³)-H amination reaction of isochroman derivatives with arylamines was developed in the presence of iron(II) salt. A variety of isochroman derivatives and primary amines were selectively transformed into the corresponding oxidative coupling products in good to excellent yield under mild conditions [ABSTRACT FROM AUTHOR]

In this manuscript we described the FeCl3/diorganyl diselenides promoted intramolecular cyclization of o-alkynyl anilines, as an alternative for the construction of functionalized 3- organoselenyl indoles. The cyclization reactions proceeded smoothly at room temperature in the presence of air giving the 3-organoselenyl indoles in good yields. Additionally, the 3-organoselenyl indoles proved to be quite useful as synthetic intermediates for the construction of more functionalized indole units through a selenium-lithium exchange reaction followed by trapping the lithium intermediate with different electrophiles. [ABSTRACT FROM AUTHOR]

A simple and concise tandem cyclization of alkynoates with amines in the presence of tert-butyl perbenzoate (TBPB) leads to 1,2,4-trisubstituted 1H-pyrroles. A variety of aromatic amines and aliphatic amines can be used in this approach, and a wide range of functionalized 1,2,4-trisubstituted 1H-pyrroles are obtained in good to excellent yields. This protocol not only corresponds to the construction of a pyrrole fragment, but also provides a new way to form C-C and C-N bonds. [ABSTRACT FROM AUTHOR]

A recyclable catalytic system comprising magnetically separable CuFe2O4 nanoparticles in a poly(ethylene glycol) medium has been established as an inexpensive, nontoxic, environmentally benign system for the amination of aryl iodides with aqueous ammonia. A wide variety of aryl iodides underwent amination to afford the corresponding aryl amines in moderate to good yields. The catalytic system was recycled five times with consistent activity. [ABSTRACT FROM AUTHOR]

The imines generated in situ from aryl amines and cyclic enol ethers undergo smooth [4+2] cycloaddition with 3,4-dihydro-2H-pyran (DHP) and 2,3-dihydrofuran (DHF) using the Brønsted acid sites on the aluminosilicate wall structure of the nanoporous catalyst under mild reaction conditions to afford the corresponding pyrano- and furo[3,2-с]quinolines, respectively, in good yields with high diastereoselectivity. The high activity of the catalyst is due to its high surface area, large pore volume, and well-ordered porous structure with high acidity. In addition, the catalyst was found to be highly stable and can be reused several times without affecting the activity of the catalyst. [ABSTRACT FROM AUTHOR]

In this work, at first, triazenes were synthesized from primary aryl amines. Afterwards, triazenes were converted into the corresponding thiophenols in one-pot using sodium sulfide in acidic media, by in situ generation of diazonium counterion beside hydrogen sulfide as anionic sulfur nucleophile at room temperature. The procedure can be a convenient shortcut for the preparation of thiophenols from primary aryl amines. [ABSTRACT FROM AUTHOR]