Abstract Suzuki–Miyaura cross coupling reactions of aryl halides with aryl boronic acids were carried out in basic ionic liquids in the presence of lithium chloride as a promoter. The coupling reactions, carried out in the absence of base and ligand, proceed in good to excellent yields with easy product isolation and catalyst recycle.
An in situ generated catalytic system based on PdCl2 and sodium sulfate exhibited excellent catalytic activity in the Suzuki–Miyaura cross-coupling reactions of aryl halides with arylboronic acids at room temperature in water. A similar catalytic system can be obtained with PdCl2 and sodium chloride or sodium acetate and is equally effective in Suzuki–Miyaura cross-coupling reactions. This method offers a mild and efficient alternative to the existing protocols since the reaction is proceeded in...
An in situ-generated catalytic system based on PdCl2 and primary amine-based ligand exhibited excellent activity (up to 98% isolated yield) in the Suzuki–Miyaura cross-coupling reactions of aryl bromides with arylboronic acids in water, at room temperature, without any additive. The efficiencies of the ligands follow the order: (C6H5)3CNH2 > C6H5CH2 NH2 > C6H5 NH2 > C6H11 NH2, which is in accordance with the palladacycle forming capacity of the respective ligands. Moderate-to-good yields (up to ...
A brief summary of selected pioneering and mechanistic contributions in the field of carbon-carbon cross-coupling reactions with palladium nanoparticles (Pd-NPs) in ionic liquids (ILs) is presented. Five exemplary model systems using the Pd-NPs/ILs approach are presented: Heck, Suzuki, Stille, Sonogashira and Ullmann reactions which all have in common the use of ionic liquids as reaction media and the use of palladium nanoparticles as reservoir for the catalytically active palladium species.
Abstract A simple catalytic system based on PdCl 2 and triphenylphosphine chalcogenides (PPh 3 X; X = O, S, Se) is found to be highly effective (up to 97% isolated yield) in the room temperature Suzuki–Miyaura reactions. Under the same experimental conditions, triphenylphosphine chalcogenides as ligands show superior activities compared to free triphenylphosphine.
#2Fatemeh Rafiee(IUT: Isfahan University of Technology)H-Index: 17
Basic ionic liquids as environmental-friendly solvents and catalysts with high activity and selectivity and easily recovered materials were used to replace traditional bases such as KOH, NaOH, K2CO3, NaHCO3, NaOAc, triethylamine, or tetrabutylammonium acetate. Using the traditional bases generally suffered from disadvantages such as waste production, corrosion and environmental problems. Basic ionic liquids offering a new possibility for developing environmentally friendly basic catalysts due to...
In this paper, we report on the synthesis and application of monosubstituted diaza - bicyclo(2.2.2)octane (dabco) cations associated with a basic anion, dicyanamide. Key prop- erties of these salts—phase transitions, density, and conductivity—were measured and com- pared to those of other common ionic liquids (ILs). Moreover, solvatochromic dyes were used to assess their solvation properties. The Heck cross-coupling reaction was evaluated in dabco-based ILs and compared with the behavior in comm...
Ionic liquids are novel solvents of interest as greener alternatives to conventional organic solvents aimed at facilitating sustainable chemistry. As a consequence of their unusual physical properties, reusability, and eco-friendly nature, ionic liquids have attracted the attention of organic chemists. Numerous reports have revealed that many catalysts and reagents were supported in the ionic liquid phase, resulting in enhanced reactivity and selectivity in various important reaction transformat...
Last. Vijai K. Rai(Allahabad University)H-Index: 18
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Abstract The first example of an ionic liquid-promoted one-pot synthesis of 3-benzamidocoumarins from salicylaldehydes and 2-pheny-1,3-oxazolan-5-one via Knoevenagel condensation-ring transformation cascades has been reported. No by-product formation, operational simplicity, ambient temperature and high yield (85–97%) are the salient features of the present synthetic protocol. After isolation of the product, the ionic liquid, [Bmim]OH can be easily recycled for further use without any loss of ef...
ABSTRACT Through N-alkylation of 1,4-diazabicyclo [2.2.2] octane with 1-bromooctane a new ionic liquid, namely 1‐octyl‐1,4‐diazabicyclo [2.2.2] octan‐1‐ium Bromide [C8DABCO+][Br−] has been synthesized and characterized by FT-IR, FT-Raman and by 1H and 13C-NMR spectroscopies. Three ionic C-H•••Br bonds were predicted by natural bond orbital (NBO), atoms in molecules (AIM) calculations and bond orders but a monodentate coordination between cation and anion is suggested because only one of them has...
This study reports an ionic liquid (IL) promoted green method to obtain diaryl thioethers useful as key intermediates for the synthesis of matrix metalloproteinase (MMP) inhibitors. The synthetic p...
Last. Basudeb Basu(University of North Bengal)H-Index: 6
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Ionic liquids (ILs) are considered as highly useful materials for potential diverse uses such as greener and more convenient alternatives to volatile organic solvents, reagents, additives, ligands and co-solvents. Thermal stability, negligible vapor pressure and high polarity with ionic environments have possibly conferred some unique physico-chemical properties and a wider electrochemical window on ILs. More importantly, these properties are tuneable, depending on variations in alkyl chains and...
Last. Diganta Sarma(Dibrugarh University)H-Index: 18
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The feasible and one of the green ways to synthesize organic compounds especially pyrazole and its derivatives are systematically presented. The one-pot synthesis of pyrazole was achieved by condensation of various hydrazines and 1,3-diketone derivatives at room temperature using transition metal-based ionic liquids. Herein, the unique combination of Fe(III) with ionic liquid is explored and utilized as an efficient homogeneous catalyst for the synthesis of pyrazole and its derivatives. The homo...
The ever-increasing interest in the Suzuki–Miyaura cross-coupling reaction (SMR) and its applications, with more than 40 years of history, has increased exponentially in the last decade, which speaks volumes about its efficiency and effectiveness. This widely used powerful method provides a practical synthetic route for the direct formation of carbon–carbon bonds, which has found considerable academic and industrial use for the production of polymers, fine chemicals and materials, in addition to...
Last. Diganta Sarma(Dibrugarh University)H-Index: 18
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Abstract Development of greener methodologies in synthetic organic chemistry has brought awareness in recent decades due to the ecological performance of green solvent media and catalytic systems. Here, we carried out the peptide bond formation reaction in one of the environmentally secure solvents, ‘ionic liquids’ in the presence of coupling reagent and in the absence of external base at room temperature, affording dipeptides in good to excellent yields.
This chapter summarizes recent progress in the application of room temperature ionic liquids as solvents and catalysts in electrophilic/onium ion chemistry, in metal-mediated bond-forming reactions, and in selected other key reactions.
Abstract Sixteen imidazolium based chiral ionic liquids (CILs) containing Br − and BF 4 − anions, derived from both enantiomers of phenylethylamine, were synthesized. The imidazole ring was constructed through a condensation reaction of formaldehyde, glyoxal and ammonium hydroxide in aqueous media resulting in a simple, versatile and environmentally friendly protocol. The CILs were synthesized with propyl, butyl, pentyl or hexyl alkyl substituents, which provoke a change of the physicochemical p...
