14300-30-2Relevant academic research and scientific papers
Design and development of cyclometalated ruthenium complexes containing thiophenyl-pyridine ligand for dye-sensitized solar cells
Li, Chung-Yen,Su, Chaochin,Wang, Hsiou-Hsuan,Kumaresan, Prabakaran,Hsu, Chia-Hsuan,Lee, I-Ting,Chang, Wei-Chun,Tingare, Yogesh S.,Li, Ting-Yu,Lin, Chia-Feng,Li, Wen-Ren
, p. 57 - 65 (2014)
Two new cyclometalated ruthenium sensitizers NC102 (1) and NC103 (2), where the two NCS- ligands of the N3 analog were replaced with the 2-thiophen-2-yl-pyridine and 2-benzo[b]thiophen-2-yl-pyridine ligands, respectively, were designed and synthesized for dye-sensitized solar cell applications. The effects of these two ligands on the photophysical behavior of ruthenium complexes were investigated by their optical, electrochemical, and photovoltaic properties. The sensitizer NC103 (2) with the fluoride substitution in the ligand exhibited the best cell performance with a short-circuit current (Jsc) of 9.45 mA/cm2, an open-circuit voltage (V oc) of 630 mV, and a fill factor (FF) of 0.71, giving an overall power conversion efficiency of (η) 4.22% under simulated AM 1.5 irradiation.
Excellent Suzuki–Miyaura catalytic activity of a new Pd(II) complex with sulfonamide–Schiff base ligand
Banik, Biplab,Tairai, Archana,Bhattacharyya, Pradip K.,Das, Pankaj
, p. 519 - 523 (2016)
A new air-stable Pd(II) complex containing a sulfonamide–Schiff base ligand has been synthesized, characterized and investigated as a catalyst for the Suzuki–Miyaura reactions of aryl halides with arylboronic acids. Theoretical calculations (B3LYP) and spectroscopic evidence suggest that the sulfonamide–Schiff base coordinates to the Pd centre through sulfonamide nitrogen (?SO2NH2) rather than imine (?CH?N). The complex shows excellent cross-coupling activity with aryl bromides in water at room temperature and aryl chlorides in isopropanol at 60°C. Copyright
Phosphine-stabilized Pd nanoparticles supported on silica as a highly active catalyst for the Suzuki-Miyaura cross-coupling reaction
Sahu, Debojeet,Das, Pankaj
, p. 3512 - 3520 (2015)
We have prepared a silica supported palladium nanocatalyst (PdNP@PPh2-SiO2) with high dispersion via a one-step reaction between commercially available 2-diphenylphosphinoethyl-functionalized silica gel (PPh2-SiO2) and PdCl2 without the assistance of an external reductant or stabilizer. The catalyst was well characterized by N2-adsorption, XRD, HRTEM, SEM-EDX and ICP analyses. The supported catalyst exhibited excellent activity for the Suzuki-Miyaura cross-coupling reactions of aryl halides (including aryl chlorides) with arylboronic acids. The facile synthesis of the catalyst combined with high product yields at relatively low catalyst loading (0.5 mol%) represents one of the most efficient silica supported heterogeneous systems for the Suzuki coupling of aryl chlorides. The catalyst could be reused several times without compromising its activity.
An unsymmetrical Schiff-base derived recyclable Pd-catalyst for Suzuki–Miyaura and Sonogashira reactions in aqueous media
Das, Pankaj,Gogoi, Achinta,Puzari, Amlan
, (2021/06/02)
Abstract: A water-soluble palladium (II) complex containing an unsymmetrical Schiff-base ligand was synthesized and applied as catalyst Suzuki–Miyaura and Sonogashira cross-coupling reactions in aqueous media. Notably, moderate to excellent yields of biaryls were obtained in Suzuki reaction with usually less reactive aryl and heteroaryl chlorides under relatively mild condition. Moderate-to-high yields of aryl-alkynes were also obtained in Sonogashira reactions using aryl bromides. Apart from hydrophilic nature, the accomplishment of reactions in water, high recyclability, broad functional group tolerance, etc., are other advantages of the system. Graphic abstract: [Figure not available: see fulltext.]
Accessing Heterobiaryls through Transition-Metal-Free C-H Functionalization
Banik, Ananya,Paira, Rupankar,Shaw, Bikash Kumar,Vijaykumar, Gonela,Mandal, Swadhin K.
, p. 3236 - 3244 (2018/03/23)
Herein we report a transition-metal-free synthetic protocol for heterobiaryls, one of the most important pharmacophores in the modern drug industry, employing a new multidonor phenalenyl (PLY)-based ligand. The current procedure offers a wide substrate scope (24 examples) with a low catalyst loading resulting in an excellent product yield (up to 95%). The reaction mechanism involves a single electron transfer (SET) from a phenalenyl-based radical to generate a reactive heteroaryl radical. To establish the mechanism, we have isolated the catalytically active SET initiator, characterizing by a magnetic study.
Palladium complexes with two unsymmetrical Schiff base ligands: Highly active catalyst for activation of chloroarenes in Suzuki-Miyaura reaction
Puzari, Amlan,Shahnaz, Nasifa,Das, Pankaj
, p. 837 - 842 (2020/06/26)
Two new unsymmetrical Schiff base derived palladium(II) complexes, [PdCl2{bis(salicylidene)-2-aminobenzamide}] (C1) and [PdCl2{N,N'-bis(salicylidene)-2-aminobenzylamine}] (C2) have been synthesized and characterized. The complexes have been explored as catalysts for the Suzuki-Miyaura cross-coupling reactions of aryl halides with arylboronic acids. An optimization study reveals that under similar experimental conditions, the complex C1 shows superior activity over the complex C2. Using the complex C1 as catalyst, less reactive chloroarenes are efficiently converted to their corresponding biaryls under relatively mild conditions (80oC, 0.5 mol% catalyst) using EtOH as an environmentally safer reaction media. Excellent yields of cross coupling products are also obtained with aryl bromides at room temperature in neat water with low catalyst loading (0.02 mol %).
Iodine-Catalyzed Synthesis of Chalcogenophenes by the Reaction of 1,3-Dienyl Bromides and Potassium Selenocyanate/Potassium Sulfide (KSeCN/K2S)
Maity, Pintu,Ranu, Brindaban C.
, p. 4369 - 4378 (2017/12/26)
The methods available for the synthesis of chalcogenophenes, in general, are associated with drawbacks of harsh conditions, use of costly metals, broad applicability, tedious purification process and low yield. To avoid these drawbacks a transition metal-free iodine-catalyzed reaction of aryl-susbstituted 1,3-dienyl bromides with potassium selenocyanate/potassium sulfide (KSeCN/K2S) leading to the corresponding selenophenes and thiophenes has been developed. Iodine is relatively benign, less expensive and readily available. Several diversely substituted selenophenes and thiophenes have been obtained by this procedure in high yields. Using this procedure 2-(4-chlorophenyl)thiophene, a key intermediate for the synthesis of a melanin concentrating hormone receptor ligand involved in the treatment of eating disorders, weight gain, obesity, depression and anxiety has been synthesized. Although the reaction is one-pot essentially it proceeds in two steps involving a selenocyanate/thiolate intermediate leading to the selenophene/thiophene. The simple operation, use of inexpensive reagents and a metal-free process make this procedure more attractive for an easy access to substituted selenophenes and thiophenes. (Figure presented.).
Activation of aryl chlorides in water for Suzuki coupling with a hydrophilic salen-Pd(II) catalyst
Shahnaz, Nasifa,Puzari, Amlan,Paul, Bidisha,Das, Pankaj
, p. 55 - 58 (2016/08/18)
For exploiting aqueous condition, we have designed a simple water-soluble palladium Schiff-base catalyst for Suzuki-Miyaura reactions of aryl halides with arylboronic acids. The reactions could be performed in neat water with aryl bromides and iodides at room temperature and with aryl chlorides at 100 °C. Good-to-excellent yields of cross-coupling products were obtained with a diverse range of aryl halides including heteroaryl halides. Interestingly, the homogeneous catalyst could be conveniently recycled with aryl bromides or chlorides for at least four times, although a progressive decrease in the product yields were noticed.
Facile synthesis of palladium nanoparticles supported on silica: An efficient phosphine-free heterogeneous catalyst for Suzuki coupling in aqueous media
Sahu, Debojeet,Silva, Ana R.,Das, Pankaj
, p. 32 - 35 (2016/08/09)
A convenient one-step method for synthesizing highly dispersed palladium nanoparticles supported on silica, without taking assistance from any external reductant or stabilizer, has been developed. The supported nanoparticles were characterized by N2-adsorption desorption, XRD, HRTEM, SEM-EDX, XPS, ICP analyses and applied as catalyst for Suzuki-Miyaura reactions of aryl halides. The reactions with aryl bromides were performed in neat water at room temperature; while the reactions with aryl chlorides were conducted in aqueous-ethanol at 90?°C. The catalyst could be reused at least three times without compromising with its activity, however from the fourth cycle a progressive decrease in yield was noticed. No aggregation of NPs was observed by the TEM analysis of the six-time used catalyst.
Palladium complex containing two sterically hindered ligands as highly efficient catalyst for Suzuki-Miyaura reaction
Shahnaz, Nasifa,Das, Pankaj
, p. 829 - 833 (2016/01/26)
A new palladium(II) complex containing two sterically hindered ligands, a P,P-bonded diphosphine and N,N-bonded Schiff base, within the same coordination sphere has been synthesized and investigated as a catalyst for the Suzuki-Miyaura cross-coupling reactions of aryl halides with arylboronic acids. The reaction was highly efficient with aryl bromides in water at room temperature and aryl chlorides in dimethylformamide under relatively mild conditions. Excellent yields of coupling products were obtained for a wide range of aryl halides including heteroaryl halides with a low loading of catalyst.
