Copper-Catalyzed Three-Component Synthesis Research Articles

Copper-Catalyzed Three-Component Synthesis of β-Hydroxysulfides from Styrene Oxide, Aryl Iodide, and Carbon Disulfide.

A copper-catalyzed three-component coupling reaction of styrene oxide, aryl iodide, and carbon disulfide for the construction of β-hydroxysulfides has been developed. In this process, readily available CS2 was used as the sulfur source to construct C-S bonds for the synthesis of phenyl-β-hydroxysulfides and (benzo[d]thiazol)-β-hydroxysulfides. This process features mild reaction conditions, simple operation, and wide substrate scope (>50 examples).

Copper-Catalyzed Three-Component Synthesis of Highly Substituted Morpholines.

Unprotected, highly substituted morpholines were obtained through a copper-catalyzed three-component reaction utilizing amino alcohols, aldehydes, and diazomalonates. The transformation was effective for diversely substituted aldehydes and for a broad range of readily available vicinal amino alcohols, including those derived from glycine, α-substituted, and α,α-disubstituted amino acids. Epimerization of morpholines using light-mediated stereochemical editing was demonstrated, and the unprotected morpholine products were readily elaborated through efficient transformations.

Copper-catalyzed three-component synthesis of pyrrole-substituted 1,2-dihydroisoquinolines

A general approach to the synthesis of 1,3-disubstituted-1,2-dihydroisoquinolines was achieved with pyrrole and various electron withdrawing groups as substituents. CuAAC reaction on enynes yielded the resulting 1,2,3-triazole which spontaneously decomposed to the corresponding ketenimine. Nucleophilic attack by pyrrole and subsequent intramolecular Aza-Michael cyclization generated 1,2-dihydroisoquinolines in moderate to good yields. The optimized conditions allow for a range of substituents with excellent reproducibility.

Copper-Catalyzed Three-Component Synthesis of Quinolines via Oxidation and Aza-Diels-Alder Reaction

Copper-Catalyzed Three-Component Synthesis of Quinolines via Oxidation and Aza-Diels-Alder Reaction

Copper-catalyzed aerobic oxidative cyclization protocol for the synthesis of quinazolines via amination of C(sp3)-H bonds of methylazaarenes

A new aerobic copper-catalyzed three-component synthesis of azaaryl-substituted quinazolines has been developed, which featured inexpensive methylazaarenes as C1 sources, easily available copper salts as the catalysts and O2 as a sole oxidant. The transformation had very good substrate applicability towards methylazaarenes, and various azaaryl-substituted quinazolines were obtained in moderate to good yields.

Direct Copper-Catalyzed Three-Component Synthesis of Sulfonamides

First introduced into medicines in the 1930s, the sulfonamide functional group continues to be present in a wide range of contemporary pharmaceuticals and agrochemicals. Despite their popularity in the design of modern bioactive molecules, the underpinning methods for sulfonamide synthesis are essentially unchanged since their introduction, and rely on the use of starting materials with preinstalled sulfur-functionality. Herein we report a direct single-step synthesis of sulfonamides that combines two of the largest monomer sets available in discovery chemistry, (hetero)aryl boronic acids and amines, along with sulfur dioxide, using a Cu(II) catalyst, to deliver a broad range of sulfonamides. Sulfur dioxide is provided by the surrogate reagent DABSO. The reaction tolerates broad variation in both coupling partners, including aryl, heteroaryl and alkenyl boronic acids, as well as cyclic and acyclic alkyl secondary amines, and primary anilines. We validate the method by showing that a variety of drugs, and drug-fragments, can be incorporated into the process.

Copper-Catalyzed Three-Component Synthesis of Thiazoles

Key words thiazoles - C–H activation - copper catalysis - sulfuration - annulation - multicomponent reaction

Copper-catalyzed three-component synthesis of pyrimidines from amidines and alcohols.

An efficient copper-catalyzed one-pot three-component reaction of amidines, primary alcohols and secondary alcohols has been developed to synthesize multisubstituted pyrimidines. The significant merits of this method involve high atom efficiency, good functional group tolerance and operational simplicity.

A Highly Efficient Copper-Catalyzed Three-Component Synthesis of 4-Aminoquinazolines

A highly efficient copper-catalyzed one-pot protocol is developed for the synthesis of 4-aminoquinazolines from easily available 2-iodo- or 2-bromobenzimidamides, aldehydes, and sodium azide. This one-pot approach proceeds via consecutive copper-catalyzed SNAr substitution, reduction, cyclization, oxidation and tautomerization. The corresponding target products (26 examples) are obtained in 50–90% yield.

Synthesis of Aminoindolizidines through the Chemoselective and Diastereoselective Catalytic Hydrogenation of Indolizines.

Indolizidines are bioactive heterocyclic compounds of great potential normally prepared following multistep routes. However, to the best of our knowledge, the synthesis of 1-aminoindolizidines has never been reported. Herein, 1-(dialkylamino)-3-substituted indolizidines have been straightforwardly synthesized using an atom-economic protocol that involves a copper-catalyzed three-component synthesis of indolizines followed by heterogeneous catalytic hydrogenation. The latter was found to be chemoselective using platinum(IV) oxide as the catalyst at 3.7 atm, providing the aminoindolizidines in modest-to-high yields (35-95%) and high diastereoselectivity (92:8 to >99:1). It has been experimentally demonstrated that the hydrogenation occurs through the intermediate 5,6,7,8-tetrahydroindolizine, which contains a pyrrole moiety. Moreover, the diastereomerically pure 1-(dibenzylamino)-3-substituted indolizidines could be further transformed into the corresponding monobenzylated or fully debenzylated aminoindolizidines by selective hydrogenolysis catalyzed by Pt/C or Pd/C, respectively, under ambient conditions.

Solvent-free copper-catalyzed three-component synthesis of 2-substituted quinazolin-4(3H)-ones

A novel and efficient approach for the synthesis of quinazoline-4(3H)-ones through a one-pot copper-catalyzed three-component reaction of isatoic anhydrides, aryl nitriles, and ammonium acetate under solvent-free conditions in good yields is described.

Copper-catalyzed three-component synthesis of aminonaphthoquinone–sulfonylamidine conjugates and in vitro evaluation of their antiproliferative activity

A series of aminonaphthoquinone–sulfonylamidine conjugates were synthesized via a copper-catalyzed three-component reaction of N-propargyl aminonaphthoquinone, sulfonyl azides and various amines. Majority of the compounds exhibited promising antiproliferative potential when evaluated against a panel of four cancer cell lines. Docking experiments of representative compounds indicated that the conjugates can occupy the ATP-binding pocket of topoisomerase-II enzyme.

Copper-catalyzed three-component synthesis of 3-aminopyrazoles and 4-iminopyrimidines via β-alkynyl-N-sulfonyl ketenimine intermediates.

3-Aminopyrazoles and 4-iminopyrimidines were efficiently prepared via copper-catalyzed three-component reactions of butadiynes, sulfonylazides, and hydrazides or imidamides. The reactions were regioselectively approached via the formation of a β-alkynyl-N-sulfonyl ketenimine intermediate which represented a new and effective 1,3-dielectrophilic equivalent in organic synthesis.

An integration of condensation/Ullmann-type coupling/bicyclization sequences: copper-catalyzed three-component direct synthesis of [1,2,4]triazolo[1,5-b]isoquinolin-5(1H)-ones.

A highly efficient three-component domino protocol has been developed for the synthesis of [1,2,4]triazolo[1,5-b]isoquinolin-5(1H)-ones from simple and readily available o-halogenated benzohydrazides, aldehydes and nitriles. This domino process involves sequential selective condensation, copper-catalyzed intermolecular C-arylation and bicyclization. Notably, the use of ligands and anaerobic conditions can be avoided in this reaction.

Copper-catalyzed three-component synthesis of 5-acetamidoimidazoles from carbodiimides, acyl chlorides and isocyanides

Only very limited methods are available for the synthesis of 5-amino imidazoles. We report in this paper that three-component reaction of acyl chlorides, carbodiimides and α-isocyanoacetates or TosMIC took place smoothly in the presence of Et3N (2.5 equiv.) and a catalytic amount of copper iodide (0.2 equiv.) to afford 1,4-disubstituted 5-acetamidoimidazoles in good yields.

Copper-Catalyzed Oxidative Three-Component Synthesis of N, N′,N″-Trisubstituted Guanidines

A copper-catalyzed three-component synthesis of trisubstituted N-aryl guanidines involving cyanamides, arylboronic acids, and amines has been developed. This operationally simple oxidative process, which is performed in the presence of K2CO3, a catalytic amount of CuCl2·2H2O, bipyridine, and oxygen (1 atm), allows the rapid assembly of N,N',N″-trisubstituted aryl guanidines.

One-Pot Copper-Catalyzed Three-Component Synthesis of Quinoxalines by Condensation and C−N Bond Formation

A novel way of synthesizing quinoxalines has been developed that involves condensation and C−N bond formation in a copper-catalyzed, one-pot, three-component reaction. The reaction was optimized when 2-iodoanilines (1.0 equiv), arylacetaldehydes (2.0 equiv), sodium azide (1.2 equiv), CuI (10 mol%), DMEDA (10 mol%), and K₂CO₃ (1.0 equiv) were reacted in DMSO at 80 °C for 20 hours. This approach was used to directly synthesize a variety of quinoxalines in moderate to good yields.

Copper-catalyzed three-component one-pot synthesis of quinazolines

Two efficient approaches to multi-substituted quinazolines by the three-component one-pot reaction of o-bromo aromatic ketones/aldehydes, ammonia water and aromatic aldehydes, or primary alcohols catalyzed by CuCl have been developed.

An Efficient Copper-Catalyzed Three-Component Synthesis of 3-C-Linked Glycosyl Iminocoumarins

An efficient general strategy was developed for the synthesis of previously unknown 3-C-linked glycosyl iminocoumarins. The strategy involves a copper-catalyzed multicomponent reaction of sugar-derived alkynes with tosyl azide and salicylaldehyde to give a diverse array of glycosyl iminocoumarins in good yields. These compounds can serve as appropriate precursors for the synthesis of the corresponding coumarin 3-C-glycosides.

Copper-Catalyzed Three-Component Synthesis of Polysubstituted Pyrroles

Copper-Catalyzed Three-Component Synthesis of Polysubstituted Pyrroles