A general and long-lived catalyst for the palladium-catalyzed coupling of aryl halides with thiols

A general catalytic system for the coupling of aryl halides and sulfonates with thiols based on the use of the CyPF-t-Bu ligand (1) is reported. The reactions catalyzed by complexes of 1 occur in excellent yields with broad scope and exhibit extraordinary turnover numbers and high tolerance of functional groups. Turnover numbers usually exceed those of previous catalysts by 2 or 3 orders of magnitude. In addition, the reactions of aryl tosylates with alkane thiols to form aryl sulfides are reported for the first time. Finally, the synthesis of a diarylsulfide from two bromoarenes was accomplished using a hydrogen sulfide surrogate.     

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.     

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.     

A general rhodium-catalyzed cross-coupling reaction of thiols with aryl iodides

The general procedure for the rhodium-catalyzed cross-coupling of thiols with aryl iodides is described. The catalytic system consists of 5 mol % of [RhCl(cod)]₂ and 10 mol % of PPh₃ as a ligand. A variety of aryl iodides reacted with thiols, giving aryl thioethers in good to excellent yields. It is important to note that the deactivated aryl iodides such as 4-iodoanisole is worked smoothly to provide the corresponding aryl thioethers in excellent yields. Functional groups such as free-amines, chloro, are all tolerated under the employed reaction conditions.     

A general and efficient CuI/BtH catalyzed coupling of aryl halides with thiols

We report an exceptionally mild, general and efficient copper catalyzed cross coupling reaction of aryl bromides and thiols using 0.5 mol % CuI and 1 mol % benzotriazole. Experimental simplicity, generality, functional group tolerance and low cost of the catalyst are advantages of the protocol.     

Simple, efficient and recyclable catalytic system for performing copper-catalyzed C-S coupling of thiols with aryl iodides in PEG and PEG-H2O

A new protocol for the coupling of aryl iodides with thiophenols or alkanethiols is reported. The reaction is catalyzed by CuI-PEG or CuI-PEG-H₂O system in the absence of ligands and volatile organic solvents. A variety of functionalized aryl sulfides are prepared in excellent yields. The isolation of the products is readily performed by the extraction with diethyl ether or petroleum ether, and the CuI-PEG catalyst can be reused without significant loss in activity. The simple catalytic system is economically competitive and environmentally friendly.     

A general palladium-catalyzed coupling of aryl bromides/triflates and thiols

We have developed an efficient palladium-catalyzed carbon-sulfur bond formation reaction of aryl bromides, triflates, and activated aryl chloride. Using this protocol, we have shown tolerance to a wide variety of aryl thiols and alkyl thiols that can also be used as sulfide equivalents. [reaction: see text]     

A general and efficient copper catalyst for the amidation of aryl halides

An experimentally simple and inexpensive catalyst system was developed for the amidation of aryl halides by using 0.2-10 mol % of CuI, 5-20 mol % of a 1,2-diamine ligand, and K(3)PO(4), K(2)CO(3), or Cs(2)CO(3) as base. Catalyst systems based on N,N'-dimethylethylenediamine or trans-N,N'-dimethyl-1,2-cyclohexanediamine were found to be the most active even though several other 1,2-diamine ligands could be used in the easiest cases. Aryl iodides, bromides, and in some cases even aryl chlorides can be efficiently amidated. A variety of functional groups are tolerated in the reaction, including many that are not compatible with Pd-catalyzed amidation or amination methodology.     

Highly efficient and functional-group-tolerant catalysts for the palladium-catalyzed coupling of aryl chlorides with thiols

The cross-coupling reaction of aryl chlorides with aliphatic and aromatic thiols catalyzed by palladium complexes of the strongly binding bisphosphine CyPF-tBu ligand (1) is reported. Most of the reactions catalyzed by complexes of ligand 1 occur with turnover numbers that exceed those of previous catalysts by two orders of magnitude. The reactions occur with excellent yields, broad scope and high tolerance of functional groups. Coupling of aryl halides with thiols in the presence of low loadings of catalysts derived from other Josiphos type ligands, as well as ligands of other structural types, are also described.     

A highly efficient catalyst for Suzuki coupling of aryl halides and bromoarylphosphine oxides

The biphenyl-based phosphine, P(o-C₆H₄C₆H₄Me)Ph₂, is a moderately bulky and electron-rich phosphine, which has been successfully applied to the palladium catalyzed Suzuki coupling of activated and deactivated aryl halides as well as bromoarylphosphines and bromoarylphosphine oxides, with low catalyst loading and good to excellent conversions and turnovers.     

Copper-catalyzed coupling of alkylamines and aryl iodides: an efficient system even in an air atmosphere

[reaction: see text] A mild method for the copper-catalyzed amination of aryl iodides is reported. This operationally simple C-N bond-forming protocol uses CuI as the catalyst and ethylene glycol as ligand in 2-propanol. A variety of functionalized aryl iodides as well as several amines were efficiently coupled using this method. This catalytic amination procedure is relatively insensitive to moisture and can be performed under an air atmosphere with comparable yield. Preliminary results on the amination of aryl bromides are also described.     

A highly efficient and widely functional-group-tolerant catalyst system for copper(I)-catalyzed S-arylation of thiols with aryl halides

A mild, general, and efficient copper-catalyzed system for C-S bond formation with high chemoselectivity and wide functional group tolerance is developed. With CuBr as catalyst and 1,2,3,4-tetrahydro-8-hydroxy-quinoline as ligand, the S-arylation of thiols with aryl halides performed well, the activated aryl iodides could take place even at room temperature, and the activated aryl bromides and chlorides give the corresponding products with good to excellent yields as well.     

An efficient copper catalyst for the formation of sulfones from sulfinic acid salts and aryl iodides

[reaction: see text] A novel copper-catalyzed method for the coupling of sulfinic acid salts and aryl iodides is described. A variety of methyl and diaryl sulfones have been formed in excellent yields.     

A phosphine-free Pd catalyst for the selective double carbonylation of aryl iodides

The first phosphine-free Pd-catalysed double carbonylation of aryl iodides is reported as a general and practical method, giving excellent conversions and selectivities for a wide range of aryl iodides and amine nucleophiles under atmospheric CO pressure.     

Pd/C: an efficient, heterogeneous and reusable catalyst for carbon monoxide-free aminocarbonylation of aryl iodides

Carbon monoxide-free aminocarbonylation is carried out efficiently via coupling of N,N-dimethylformamide (DMF) with aryl iodides using Pd/C as a heterogeneous catalyst. The catalyst exhibits remarkable activity and is reusable for up to three consecutive cycles. The reaction is applicable to a wide variety of substituted aryl iodides with different steric and electronic properties providing excellent yields of the corresponding tertiary amides.     

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.     

Efficient ligand-free nickel-catalyzed C-S cross-coupling of thiols with aryl iodides

NiCl₂·6H₂O efficiently catalyzes the C-S bond formation by the cross-coupling of aryl iodides with thiols in tetrabutylammonium bromide (TBAB) in excellent yield. The reaction functions in air and the NiLn-TBAB can be recovered and recycled without the loss of activity.