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International audience; Several catalytic reactions such as Ullmann, Chan–Lam, Huisgen 1,3-dipolar cycloaddition, [2 + 3] cycloaddition, condensation, and coupling reactions under suitable conditions have been used for the synthesis of fundamental structures containing a carbon–nitrogen (C–N) bond. Graphene oxide (GO) and its derivatives as heterogeneous catalysts have attracted considerable attention for the synthesis of organic building blocks. Loading of GO derivatives with copper complexes or nanoparticles, as one of the most abundant and low toxic transition metals, allowed to design new composites with predominant ability to C–N bond formation. In this review article, we present a comprehensive overview on the synthesis of building blocks containing a C–N bond such as amines, triazoles, tetrazoles, propargyl amines, imidazoles, and benzodiazepines using GO derivatives loaded with copper complexes or nanoparticles. © 2021 John Wiley and Sons, Ltd.

The first Negishi cross-coupling of amides for the synthesis of versatile diaryl ketones by selective C−N bond activation under exceedingly mild conditions is reported. The cross-coupling was accomplished with bench-stable, inexpensive precatalyst [Ni(PPh3)2Cl2] that shows high functional-group tolerance and enables the synthesis of highly functionalized diaryl ketone motifs. The coupling occurred with excellent chemoselectivity favoring the ketone (cf. biaryl) products. Notably, this process represents the mildest conditions for amide N−C bond activation accomplished to date (room temperature

The use of tert-butanesulfinamides as nitrogen nucleophiles in carbon-nitrogen bond forming reactions is reviewed. This field has grown in the shadow of the general interest in N-tert-butanesulfinyl imines for asymmetric synthesis and occupies now an important place in its own right in the chemistry of the chiral amine reagent tert-butanesulfinamide. This article provides an overview of the area and emphasizes recent contributions wherein the tert-butanesulfinamides act as chiral auxiliaries or perform as nitrogen donors in metal-catalyzed amination reactions.

The first Ni-catalyzed Suzuki-Miyaura coupling of amides for the synthesis of widely occurring biaryl compounds through N-C amide bond activation is reported. The reaction tolerates a wide range of electron-withdrawing, electron-neutral, and electron-donating substituents on both coupling partners. The reaction constitutes the first example of the Ni-catalyzed generation of aryl electrophiles from bench-stable amides with potential applications for a broad range of organometallic reactions.

Oxidative dearomatization of N-tosylated anilines and subsequent reaction with cyanoacetates and related cyano substituted activated methylene compounds followed by the addition of an external nucleophile offers a straightforward access to arenes substituted with a quarternary carbon.

The metal coordination complex K4[Fe(CN)6] is an efficient and environmentally benign catalyst for the synthesis of imidazolines and benzimidazoles from various aldehydes and 1,2-diamines in aqueous medium at room temperature. This protocol gives excellent yield of product with desired purity.

Imination and amidation of sulfides, sulfoxides, and olefins using 4H-1,2,4-triazole-4-amine as a nitrogen source with PhI(OAc)2 as an oxidant were achieved in moderate to high yields without the addition of a catalyst. The carbon–nitrogen and sulfur–nitrogen bond forming reactivity is consistent with a nitrene insertion mechanism in which the reactivity generally increases with decreasing N–H bond dissociation energy of the nitrogen source and increasing oxidation potential of the oxidant.

Azodicarboxylates have found applications in electrophilic amination reactions and in pericyclic reactions. The nucleophilic trigger in Mitsunobu reactions, that is, the zwitterion formed from triphenylphosphine and dialkyl azodicarboxylate, has been utilized recently in various heterocyclic constructions. This Focus Review summarizes the potential utility of azodicarboxylates in various carbon-nitrogen bond-forming reactions.

The carbon–nitrogen bond of β-lactams is cleaved by palladium(0), and an alkene is intramolecularly inserted therein. The following reductive elimination produces nitrogen-containing benzo-fused tricycles in good to high yields.

Organocatalysis and cooperative catalysis are fast growing research areas. In these fields, cinchona alkaloids and their derivatives play a major role. The ready availability of both pseudo-enantiomeric pairs from natural sources makes them outstanding catalysts for reactions including oxidation, alkylation, cycloaddition, and carbene insertion. This short review focuses on recent achievements in the field of asymmetric carbon-nitrogen atom bond formation reactions using cinchona alkaloids and their derivatives.

We have studied several enzymes involved in cleavage and synthesis of a C-N single or triple bond (e.g., nitrilase, nitrile hydratase, amidase, isonitrile hydratase, N-substituted formamide deformy...

Gone fishing: When propiophenone and related ethyl ketones are treated with morpholine in the presence of K(3)PO(4), chlorobenzene, and [Ni(cod)(2)]/PMe(3) catalyst, a carbon-nitrogen bond is formed selectively at the beta position (see scheme; cod = cycloocta-1,5-diene). Secondary amines were employed as substrates to give the corresponding beta-enaminones.

The title reaction represents a novel method for the synthesis of α-ketoamides such as (II) and (V).

4-Amino-4-H-1,2,3-triazole (II) serves as a nitrogen source for the imination and amidation of olefins, sulfides, and sulfoxides via nitrene insertion in the absence of any catalyst under mild conditions.

The unactivated C—N bond of various aryl hydrazines (I), (IV), (VII), and (X) is cleaved under mild conditions by Pd(0) with the assistance of Pd(II).

A range of ketones and aldehydes smoothly undergo asymmetric SN1 α-alkylation with N-benzylic sulfonamides in the presence of 10 mol % of a chiral imidazolidinone and trifluoroacetic acid to give the corresponding products in good to excellent yields and with good enantioselectivity. This chemistry has been successfully extended to the asymmetric desymmetrization of 4-substituted cyclohexanones, which exhibits greater than 99:1 diastereoselectivity and good enantioselectivity.

A palladium-catalyzed carbonation–diketonization reaction of terminal alkenes via carbon–nitrogen bond cleavage under an atmosphere of oxygen has been developed. A series of 1,2-diketones were readily prepared from the reaction of aromatic terminal alkenes with nitroalkanes.

The general method allows the synthesis of N-substituted anilines and tolerates a broad spectrum of functionalities.

The reaction of tertiary amines (I) with ethyl diazoacetate in the presence of iron or manganese salts leads to N-disubstituted glycine derivatives (III).

The reduction of aryl aldehydes and ketones in neutral medium, to the corresponding hydrocarbons via carbon-nitrogen bond cleavage of the intermediate N-(arylmethyl)anilines with low-valent titanium reagents is described. It provides a mild, convenient and selective pathway for deoxygenation of carbonyls without the production of any side product.

The application of the samarium diiodide fragmentation reaction to 5,5-disubstituted oxopyrrolidines (I) leads to a regioselective carbon—nitrogen bond cleavage affording the 4,4-disubstituted cleavage products (II).

Nickel peroxide selectively cleaves the α-carbon-nitrogen bond of glycine residues in dipeptide derivatives to give the corresponding amides. The glycine selectivity is attributable to preferential complexation of the reactant residue to nickel peroxide and subsequent reaction via a stable α-centred glycyl radical. The oxidation process serves as a chemical model for peptidylglycine α-amidating monooxygenase (PAM) and, in addition, may have potential for the synthesis of α,β-didehydro amino acid residues within peptides.

Nitrosocarbonyl intermediates, generated at r.t. by the mild oxidation of nitrile oxides, undergo clean ene reactions with tetramethyl- and trimethyl-ethylene and with cyclohexene. With less substituted ethylenes the ene pathway is still active but the oxidation step of the nitrile oxides competes with the cycloadditions to the olefins.

Intramolecular addition of an aryl radical to the nitrogen of an imidate ester cyclized in the 5-exo-trig mode to form the CN bond, with no 6-endo-trig product being detected.

Department of Chemistry, Yonsei University, Seoul 120-749, KoreaReceived September 24, 199830 Bull. Korean Chem. Soc. 1999, Vol. 20, No. 1 Communications to the Editor Carbon-nitrogen bond cleavage by transition metal com-plexes has been one of the recent developments in organo-metallic chemistry

A facile synthesis of sulfonylamidinesvia carbon–nitrogen bond formation mediated by FeCl3 was developed and an interesting major product of cyclic tertiary amine was observed, which showed the good selectivity of FeCl3-mediated activation of cyclic α-C–H bonds of cyclic tertiary amines.

Triethyl phosphite deoxygenation of 2-(2-nitrophenyl)imidazo[1,2-a][1,8]naphthyridine (3) led to the C-insertion to give the indoloimidazonaphthyridine 5. Our attempt to promote the N-insertion by blocking the C-3 position failed. Triethyl phosphite deoxygenation of 1-nitroso-2-(4-fluorophenyl)imidazo[1,2-a][1,8]-naphthyridine (12) led to the corresponding amine structure (15). Thermolysis and photolysis of 6,8-dimethyl-2-(2-azidophenyl)imidazo[1,2-a][1,8]naphthyridine (17) are also reported.

Gone fishing: When propiophenone and related ethyl ketones are treated with morpholine in the presence of K(3)PO(4), chlorobenzene, and [Ni(cod)(2)]/PMe(3) catalyst, a carbon-nitrogen bond is formed selectively at the beta position (see scheme; cod = cycloocta-1,5-diene). Secondary amines were employed as substrates to give the corresponding beta-enaminones.

The RuH2(CO)(PPh3)3-catalyzed reaction of 2-amino-6-methylacetophenone with phenylboronic acid 2,2-dimethyl-1,3-propanediol ester in refluxing toluene gave the corresponding phenylation product in 83% yield via aryl carbon−nitrogen bond cleavage. This reaction involves two notable features: (1) the coupling proceeds via the oxidative addition of an aryl carbon−nitrogen bond in anilines to the ruthenium complex, and (2) C−C bond formation takes place via transmetalation between the Ru−NR2 species and organoboronates.

We present here carbon-nitrogen bond formation via a coupling reaction of 2-iodo-selenophene catalyzed by Cu(I) in the presence of a base and an inexpensive ligand, and establish the first route to obtaining 2-nitrogen-selenophene derivatives in good yields. We can anticipate that this reaction works well with oxazolidinones, lactams, and aliphatic and aromatic amides, as nitrogen sources, in the absence of any supplementary additives. In addition, the reaction proceeded cleanly under mild reaction conditions and was sensitive to the ratio of amide/2-iodo-selenophene, as well as the nature of the ligand, base, and solvent.

(+)-Febrifugine, a potential anti-malarial piperidine alkaloid, was synthesized from (45)-hydroxyproline methyl ester, stereoselectively, where a samarium diiodide-promoted carbon-nitrogen bond cleavage reaction was involved as a key reaction. A stereocontrolled formal synthesis of (-)-isofebrifugine was also described.