Sonogashira Coupling Reaction In Water Research Articles

Palladium-Catalyzed Mizoroki-Heck and Copper-Free Sonogashira Coupling Reactions in Water Using Thermoresponsive Polymer Micelles.

A few kinds of thermoresponsive diblock copolymers have been synthesized and utilized for palladium-catalyzed coupling reactions in water. Poly(N-isopropylacrylamide) (PNIPAAm) and poly(N,N-diethylacrylamide) (PDEAAm) are employed for thermoresponsive segments and poly(sodium 4-styrenesulfonate) (PSSNa) and poly(sodium 2-acrylamido-methylpropanesulfonate) (PAMPSNa) are employed for hydrophilic segments. Palladium-catalyzed Mizoroki–Heck reactions are performed in water and the efficiency of the extraction process is studied. More efficient extraction was observed for the PDEAAm copolymers when compared with the PNIPAAm copolymers and conventional surfactants. In the study of the Sonogashira coupling reactions in water, aggregative precipitation of the products was observed. Washing the precipitate with water gave the product with satisfactory purity with a good yield.

Synthesis of Sulfonamide-Based Ynamides and Ynamines in Water.

Ynamides, though relatively more stable than ynamines, are still moisture-sensitive and prone to hydration especially under acidic and heating conditions. Here we report an environmentally benign, robust protocol to synthesize sulfonamide-based ynamides and arylynamines via Sonogashira coupling reactions in water, using a readily available quaternary ammonium salt as the surfactant.

Green, cost‐effective and efficient procedure for Heck and Sonogashira coupling reactions using palladium nanoparticles supported on functionalized Fe3O4@SiO2 by polyvinyl alcohol as a highly active, durable and reusable catalyst

A novel heterogenized organometallic catalyst was synthesized by coordinating palladium with polyvinyl alcohol‐functionalized Fe3O4@SiO2 nanospheres. This novel catalyst was characterized using Fourier transform infrared spectroscopy, X‐ray diffraction, transmission electron microscope, field emission scanning electron microscope, dynamic light scattering, UV–vis spectroscopy, X‐ray photoelectron spectroscopy, energy dispersive X‐ray analysis, thermogravimetric analysis and inductively coupled plasma analysis. The prepared palladium nanoparticles supported on polyvinyl alcohol functionalized Fe3O4@SiO2 nanoparticles were successfully applied as a magnetically recyclable catalyst in Heck and Sonogashira coupling reactions in water. They showed remarkable activity toward aryl halides (I, Br, Cl) using very low palladium loading in excellent yields and demonstrated high TONs (mmol of product per mmol of catalyst). Also, the catalyst could be magnetically separated and reused seven times without any appreciable loss of catalytic activity.

Synthesis of new 2-substituted pyrazolo[5,1-b][1,3]oxazoles via Sonogashira coupling reactions in water

New 2-substituted pyrazolo[5,1-b][1,3]oxazoles are synthesized through the Sonogashira coupling reaction of 2-iodomethyl-6-methylpyrazolo[5,1-b][1,3]oxazole with terminal alkynes in the presence of a palladium catalyst. This process is carried out in the absence of any copper salt, and provides an eco-friendly and efficient method for the synthesis of the products in water in good-to-high yields. Some of the compounds synthesized were screened for their in vitro anti-oxidant activity using the DPPH (2,2-diphenyl-2-picrylhydrazyl) assays.

Melamine‐Based Microporous Network Polymer Supported Palladium Nanoparticles: A Stable and Efficient Catalyst for the Sonogashira Coupling Reaction in Water

AbstractA template consisting of a melamine‐based microporous polymer network was synthesized and utilized as a solid support to stabilize palladium nanoparticles; the resulting Pd/SNW1 material showed good catalytic activity in copper‐free Sonogashira coupling in water. Various aryl iodides were efficiently coupled with arylacetylenes under very low catalyst loadings in an environmentally benign medium. Hot filtration tests confirmed the heterogeneity of the catalyst, which was reused under the optimized conditions without any significant change in its activity. This simple preparation of the catalyst, the stability of the catalyst, product selectivity, and easy recovery and regeneration indicate the possible utilization of this catalytic system in a multitude of catalyzed reactions and industrial processes.

Facile and surfactant-free synthesis of Pd nanoparticles by the extract of the fruits of Piper longum and their catalytic performance for the Sonogashira coupling reaction in water under ligand- and copper-free conditions

This work reports a facile synthesis of palladium nanoparticles (Pd NPs) by the extract of the fruits of Piper longum without any stabilizer or surfactant.

Sonogashira Coupling Reaction in Water Using a Polymer-Supported Terpyridine–Palladium Complex under Aerobic Conditions

Sonogashira Coupling Reaction in Water Using a Polymer-Supported Terpyridine–Palladium Complex under Aerobic Conditions

A novel polymer containing phosphorus-nitrogen ligands for stabilization of palladium nanoparticles: an efficient and recyclable catalyst for Suzuki and Sonogashira reactions in neat water.

A new polymer containing phosphorus and nitrogen ligands was successfully synthesized, characterized and used for the stabilization of highly monodispersed palladium nanoparticles having an average diameter of 2-3 nm. The thermally stable heterogeneous catalyst was successfully applied in Suzuki-Miyaura and copper-free Sonogashira-Hagihara coupling reactions of aryl halides under low palladium loading conditions. Reactions were proceeded in neat water without using any organic co-solvents. The catalyst was successfully recycled for the sample Suzuki-Miyaura reaction nine consecutive times with small drop in catalytic activity.

A heterogeneous and reusable nanopolymer-supported palladium catalyst for the copper- and phosphine-free Sonogashira coupling reaction under aerobic conditions in water

We report here the synthesis of a nanopolymer-supported palladium(II) complex catalyst, [PS-tet-Pd(II)] using a simple protocol. The catalyst was characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM), FT-IR, and energy dispersive X-ray spectroscopy (EDS). PS-tet-Pd(II) proves to be a useful heterogeneous catalyst in the copper- and phosphine-free Sonogashira coupling reaction in water. The catalyst can be recovered from the reaction mixture by simple filtration and reused several times without any significant loss of catalytic activity.

Pd nanoparticles immobilized on poly(NIPAM-co-4-VP) hydrogel: Highly active and reusable catalyst for carbon–carbon coupling reactions in water

Poly(N-isopropylacrylamide-co-4-vinylpyridine) [poly(NIPAM-co-4-VP)] co-polymer exhibited inverse temperature solubility with a lower critical solution temperature (LCST) in water. Pd nanoparticles were immobilized on these poly(NIPAM-co-4-VP) hydrogels. The heterogeneous Pd catalyst showed high catalytic activities for carbon–carbon coupling reactions, such as Suzuki–Miyaura, Heck–Mizoroki, and Sonogashira coupling reactions in water. The Pd catalyst immobilized on poly(NIPAM-co-4-VP) hydrogel (NIPAM:4-VP = 1:1 M ratio) showed an excellent recyclability and excellent yield for carbon–carbon coupling reactions.

A reusable polystyrene-supported copper(II) catalytic system for N-arylation of indoles and Sonogashira coupling reactions in water

A polymer–anchored Cu(II) N,N-dimethylethylenediamine complex was prepared and characterized by various techniques, including Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), energy dispersive X-ray spectroscopy (EDX), atomic absorption spectroscopy (AAS), and thermogravimetric analysis (TGA). This heterogeneous Cu(II) catalyst, efficiently works for the N-arylation of indoles and Sonogashira coupling of terminal alkynes with aryl halides in aqueous medium. The effect of solvent, and base for the CN, and CC coupling reactions were reported. Further, the catalyst can be easily recovered quantitatively by simple filtration and reused up to four times without significant loss of its catalytic activity.

A general catalyst for Suzuki-Miyaura and Sonogashira reactions of aryl and heteroaryl chlorides in water.

We report the synthesis of 2-(3-sulfonatomesityl)-5-sulfonatoindenyl)dicyclohexylphosphine hydrate sodium salt and its use in palladium-catalyzed Suzuki-Miyaura and Sonogashira coupling reactions in water (and biphasic water-organic solvent mixtures) to prepare a variety of functionalized biaryls and aryl alkynes in excellent yield.

ChemInform Abstract: Recyclable Polymer‐Supported Nanometal Catalysts in Water

Two types of polymer-supported nanometal catalysts with high catalytic activity and recyclability in water have been developed. One catalyst was composed of linear polystyrene-stabilized metal nanoparticles (PS-MtNPs). A palladium catalyst (PS-PdONPs) was prepared in water by the thermal decomposition of Pd(OAc)2 in the presence of polystyrene. The degree of immobilization of Pd, but not the size of the Pd nanoparticles, was dependent on the molecular weight and cross-linking of the polystyrene. The PS-PdONPs exhibited high catalytic activity for Suzuki, Heck, and Sonogashira coupling reactions in water and they could be recycled without loss of activity. Linear polystyrene was also suitable as a stabilizer for in situ generated PdNPs and PtNPs. The second catalyst was a polyion complex that was composed of poly[4-chloromethylstyrene-co-(4-vinylbenzyl)tributylammonium chloride] and poly(acrylic acid)-stabilized PdNPs (PIC-PdNPs). Aggregation and redispersion of PIC-PdNPs were easily controlled by adjusting the pH value of the solution.

Recyclable Polymer‐Supported Nanometal Catalysts in Water

Two types of polymer-supported nanometal catalysts with high catalytic activity and recyclability in water have been developed. One catalyst was composed of linear polystyrene-stabilized metal nanoparticles (PS-MtNPs). A palladium catalyst (PS-PdONPs) was prepared in water by the thermal decomposition of Pd(OAc)2 in the presence of polystyrene. The degree of immobilization of Pd, but not the size of the Pd nanoparticles, was dependent on the molecular weight and cross-linking of the polystyrene. The PS-PdONPs exhibited high catalytic activity for Suzuki, Heck, and Sonogashira coupling reactions in water and they could be recycled without loss of activity. Linear polystyrene was also suitable as a stabilizer for in situ generated PdNPs and PtNPs. The second catalyst was a polyion complex that was composed of poly[4-chloromethylstyrene-co-(4-vinylbenzyl)tributylammonium chloride] and poly(acrylic acid)-stabilized PdNPs (PIC-PdNPs). Aggregation and redispersion of PIC-PdNPs were easily controlled by adjusting the pH value of the solution.

Recent progress and current applications of Sonogashira coupling reaction in water

The use of aqueous media in palladium‐catalyzed reactions has become popular because water‐based synthetic processes are inherently safer as well as being inexpensive. Moreover, it does not require dry solvents, and the products may easily be isolated by extraction, which greatly facilitates the operation. Thus the use of water in palladium‐catalyzed reactions represents one of the most economically and environmentally viable options for many organic transformations. In this review, recent developments of Sonogashira reaction in water or aqueous media will be disclosed. Copyright © 2013 John Wiley & Sons, Ltd.

ChemInform Abstract: Cross‐Linked Polymer‐Supported Palladium‐Catalyzed Carbonylative Sonogashira Coupling Reaction in Water.

Abstract A cross-linked polymer-supported ionic liquid immobilized palladium catalyst, which is prepared by reaction of the Pd(OAc)2 with copolymer of 3-butyl-1-vinylimidazolium iodide and divinylbenzene, was well characterized and employed as an effective heterogeneous catalyst for carbonylative Sonogashira coupling reaction of aryl iodides with terminal alkynes in water, affording the corresponding α,β-alkynyl ketones in good to excellent yields. The catalytic system not only solves the basic problem of homogeneous palladium catalyst recovery and reuse but also avoids the use of toxic phosphine ligands. The stability of supported palladium was also discussed.

Linear Polystyrene-Stabilized Palladium Nanoparticles-Catalyzed C–C Coupling Reaction in Water

Linear polystyrene-stabilized PdO nanoparticles (PS-PdONPs) were prepared in water by thermal decomposition of Pd(OAc)(2) in the presence of polystyrene. The immobilization degree of palladium was dependent on the molecular weight of polystyrene, while the size of the Pd nanoparticles was not. Linear polystyrene-stabilized Pd nanoparticles (PS-PdNPs) were also prepared using NaBH(4) and phenylboronic acid as reductants. The catalytic activity of PS-PdONPs was slightly higher than that of PS-PdNPs for Suzuki coupling reaction in water. PS-PdONPs exhibited high catalytic activity for Suzuki and copper-free Sonogashira coupling reactions in water and recycled without loss of activity.

Cross-linked polymer supported palladium catalyzed carbonylative Sonogashira coupling reaction in water

A cross-linked polymer-supported ionic liquid immobilized palladium catalyst, which is prepared by reaction of the Pd(OAc)2 with copolymer of 3-butyl-1-vinylimidazolium iodide and divinylbenzene, was well characterized and employed as an effective heterogeneous catalyst for carbonylative Sonogashira coupling reaction of aryl iodides with terminal alkynes in water, affording the corresponding α,β-alkynyl ketones in good to excellent yields. The catalytic system not only solves the basic problem of homogeneous palladium catalyst recovery and reuse but also avoids the use of toxic phosphine ligands. The stability of supported palladium was also discussed.

ChemInform Abstract: Polymer‐Supported Palladium Perfluorooctanesulfonate [Pd(OPf)2]: A Recyclable and Ligand‐Free Palladium Catalyst for Copper‐Free Sonogashira Coupling Reaction in Water under Aerobic Conditions.

AbstractChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 200 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Polymer-supported palladium perfluorooctanesulfonate [Pd(OPf) 2]: A recyclable and ligand-free palladium catalyst for copper-free Sonogashira coupling reaction in water under aerobic conditions

Amberlyst A-21, a kind of well-known and cheap polymeric material, was treated with palladium perfluorooctanesulfonate [Pd(OPf) 2] giving a reagent with a palladium loading of 1.94 (wt%). The polymer-supported fluorous palladium catalyzes the highly efficient Sonogashira coupling reaction in water. The reactions can be performed under copper- and ligand-free conditions in an air atmosphere. The palladium catalyst is easily separated and can be reused several times without a significant loss of catalytic activity.