Copper-catalyzed coupling of hydroxylamines with aryl iodides

An efficient method for the copper-catalyzed N-arylation of hydroxylamines with aryl iodides is described. A variety of N- and O-functionalized hydroxylamines were transformed in good to excellent yield with a broad range of aryl coupling partners. Methods for the selective deprotection of either the N- or O-substituents for further functionalization are also described.     

Copper-catalyzed coupling of aryl iodides with aliphatic alcohols

[reaction: see text] A simple and mild method for the coupling of aryl iodides and aliphatic alcohols that does not require the use of alkoxide bases is described. The reactions can be performed in neat alcohol. For more precious alcohols, the etherification was carried out in toluene as solvent using 2 equiv of alcohol. Additionally, the cross-coupling of an optically active benzylic alcohol with an unactivated aryl halide was demonstrated to proceed with complete retention of configuration.     

Copper-catalyzed cross-coupling of aryl iodides and aryl acetylenes using microwave heating

An efficient copper-catalyzed cross-coupling of aryl iodides with aryl acetylenes under microwave irradiation is described. The reaction proceeds under microwave heating with 10 mol % CuI and 2 equiv Cs₂CO₃ in 43-87% yields.     

Copper-catalyzed cross-coupling of diethyl phosphonate with aryl iodides

Cross-coupling of diethyl phosphonate with aryl iodides was performed using copper(I) iodide complexes with various bidentate ligands as catalysts.     

Copper-catalyzed Ullmann coupling under ligand- and additive-free conditions. Part 2: S-Arylation of thiols with aryl iodides

S-Arylation of a wide variety of substituted aryl and aliphatic thiols with aryl halides catalyzed by copper iodide under mild ligand- and additive-free conditions (ⁿBu₄NBr, PhMe, NaOH, reflux, 22 h) is accomplished in good to excellent product yields (up to 96%).     

A mild and efficient copper-catalyzed coupling of aryl iodides and thiols using an oxime-phosphine oxide ligand

A mild and efficient copper-catalyzed system for the coupling of aryl iodides and thiols was developed using a readily prepared and highly stable oxime-phosphine oxide ligand. Good to excellent yields were obtained.     

A general,efficient, and inexpensive catalyst system for the coupling of aryl iodides and thiols

An efficient copper-catalyzed carbon-sulfur bond formation reaction was developed. This method is particularly noteworthy given its experimental simplicity, high generality, and exceptional level of functional group toleration and the low cost of the catalyst system. [reaction: see text]     

Copper-catalyzed synthesis of 2-sulfenylindoles from indoline-2-thiones and aryl iodides

A novel and efficient method for synthesis of 2-sulfenylindole via copper-catalyzed coupling reaction of indoline-2-thiones with aryl iodides has been developed. A series of N-substituted and N-free 2-sulfenylindole were obtained in high yields. Furthermore, the method was employed to synthesis of benzothieno[2,3-b]indoles from indoline-2-thiones with 1,2-diiodobenzene in the presence of CuI and Pd(OAc)₂ as catalysts.     

Copper-catalyzed domino coupling reaction: an efficient method to synthesize oxindoles

An efficient and novel procedure for a copper catalyzed domino coupling reaction has been developed, which afforded various oxindoles in good to excellent yields with tolerance of various substituents. In addition, this method could be applied to synthesize horsfiline and coerulescine in few steps with high total yields.     

Copper-catalyzed trifluoromethylation of aryl iodides with potassium (trifluoromethyl)trimethoxyborate

Potassium (trifluoromethyl)trimethoxyborate is introduced as a new source of CF(3) nucleophiles in copper-catalyzed trifluoromethylation reactions. The crystalline salt is stable on storage, easy to handle, and can be obtained in near-quantitative yields simply by mixing B(OMe)(3), CF(3)SiMe(3), and KF. The trifluoromethylation reagent allows the conversion of various aryl iodides into the corresponding benzotrifluorides in high yields under mild, base-free conditions in the presence of catalytic quantities of a Cu(I)/1,10-phenanthroline complex.     

Nickel-catalyzed decarboxylative coupling of an alkynyl carboxylic acid with aryl iodides

A decarboxylative coupling reaction with an alkynyl carboxylic acid and aryl iodides in the presence of a nickel catalyst was developed. When the reaction was conducted with NiCl₂ (10 mol%), Xantphos (15 mol%), Mn (1.0 equiv), and Cs₂CO₃ (1.5 equiv), the desired diaryl alkynes were formed in moderated to good yields. Furthermore, this method does not produce the diyne, which is formed in the homocoupling of alkynyl carboxylic acids.     

水相中钯催化碘代芳烃Ullmann偶联反应研究

研究了吸电子基团的贫电碘代芳烃的Ullmann偶联反应,该反应使用Pd(OAc)2为催化剂,K2CO3为添加剂,以丙酮-水混合液为溶剂,不需要添加额外的还原剂,收率为55-87%。在通过了一系列的试验后,可以认为该反应中的溶剂及碱没有起还原作用,而是碘代芳烃自身作为还原剂,完成整个催化反应的,并首次提出了一种不需要外加还原剂的Pd(II)/Pd(IV)/Pd(II)的催化循环机理。     

Efficient copper-catalyzed coupling of aryl iodides and thiobenzoic acid

A highly efficient copper-catalyzed coupling reaction of aryl iodides and thiobenzoic acid, using 10 mol % of copper iodide, 20 mol % of 1,10-phenanthroline, and ⁱPr₂NEt in toluene, was developed. This methodology is applicable to a variety of aryl iodides.     

Intermolecular Heck-type coupling of aryl iodides and allylic acetates

[reaction: see text] A palladium-catalyzed arylation of allylic acetates followed by beta-acetoxy elimination was shown to produce Heck-type coupling products. Optimal reaction conditions employed ligand-free palladium on carbon in the presence of tetrabutylammonium chloride, a trialkylamine base, and water.     

Ligand-free copper-catalyzed C-S coupling of aryl iodides and thiols

A protocol for the copper-catalyzed aryl-sulfur bond formation between aryl iodides and thiophenols is reported. The reaction is catalyzed by a low amount (1-2.5 mol %) of readily available and ligand-free copper iodide salt. A variety of diaryl thioethers are synthesized under relatively mild reaction conditions with good chemoselectivity and functional group tolerance.     

An Ullmann coupling of aryl iodides and amines using an air-stable diazaphospholane ligand

A copper-based catalytic system, using an air-stable diazaphospholane as the ligand, was developed for an efficient Ullmann reaction between aryl iodides and alkyl or heterocyclic amines.     

Highly efficient and practical phosphoramidite-copper catalysts for amination of aryl iodides and heteroaryl bromides with alkylamines and N(H)-heterocycles

A highly efficient copper-catalyzed system using phosphoramidite as ligands was applied to N-arylation of alkylamines and N(H)-heterocycles with aryl iodides and heteroaryl bromides. The reactions were carried out in relative mild conditions and good to excellent yields were obtained.     

Mild and efficient copper-catalyzed amination of aryl bromides with primary alkylamines

[reaction: see text] An efficient copper-catalyzed amination of aryl bromides with primary alkylamines was developed that uses commercially available diethylsalicylamide as the ligand. This amination reaction can be performed at 90 degrees C in good yield. A variety of functional groups are compatible with these reaction conditions. Preliminary results show that this reaction can be carried out under solvent-free conditions with comparable yields.     

Copper-catalyzed N-arylation of sulfonamides with aryl bromides and iodides using microwave heating

The copper-catalyzed N-arylation of sulfonamides with a variety of aryl bromides and iodides using microwave heating is described.     

Copper-catalyzed cross-coupling of sulfonamides with aryl iodides and bromides facilitated by amino acid ligands

A highly general, convenient, and inexpensive catalyst system was developed for the N-arylation of sulfonamides with aryl iodides or bromides by using 5-20 mol % of CuI as catalyst, 20 mol % of N-methylglycine (for aryl iodides) or N,N-dimethylglycine (for aryl bromides) as ligand, and K₃PO₄ as base.