7581-94-4Relevant academic research and scientific papers
Synthesis and application of Cu(II) immobilized MCM-41 based solid Lewis acid catalyst for aminolysis reaction under solvent-free condition
Chaudhary, Garima,Gupta, Neha,Singh, Amit Pratap
, (2021/07/22)
In this paper, a Cu(II) immobilized periodic mesoporous organosilica (PMOs) was synthesized and used as a reusable solid Lewis acid catalyst for the aminolysis of epoxides under solvent-free conditions. An amide-based ligand, L-propylsilyl (1) having a specific binding pocket was prepared and fabricated on mesoporous MCM-41 to produce mesoporous organosilica L-propylsilyl@MCM-41 (2). Further, it has been utilized for anchoring Cu(II) ions under controlled reaction conditions to yield solid Lewis acid catalyst Cu(II)-L-propylsilyl@MCM-41 (3). The synthesized catalyst 3 exhibits significantly higher catalytic activity for aminolysis compared to hitherto known solid Lewis acid catalysts. An extensive range of β-amino alcohols with high regio and stereoselectivity were prepared by using catalyst 3. The catalyst was recovered easily and reused eight times without any loss in its catalytic activity. Furthermore, the synthesis of clinically significant propranolol (β-blocker) from α- naphthyl glycidyl ether was attained successfully using catalyst 3 in a very decent yield.
Syntheses, structures and catalytic activities of low-coordinated rare-earth metal complexes containing 2,2′-pyridylpyrrolides
Du, Jun,Zhou, Shuangliu,Zhang, Xiuli,Zhang, Lijun,Cui, Peng,Huang, Zeming,Wei, Yun,Zhu, Xiancui,Wang, Shaowu
, (2019/11/20)
Reactions of the ligand precursors 2-(2′-pyridyl)-3,5-Me2-pyrrole (L1H) and 2-(2-pyridyl)-3,4,5-Me3-pyrrole (L2H) with [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 in toluene afforded a series of low-coordinated rare-earth metal bis-amido complexes L1RE[N(SiMe3)2]2 [RE = Y (1a), Dy (1b), Er (1c), Yb (1d)] and L2RE[N(SiMe3)2]2 [RE = Y (2a), Dy (2b), Er (2c), Yb (2d)]. With the ionic radius of rare-earth metal increasing, the reaction of L1H and [(Me3Si)2N]3RE(μ-Cl)Li(THF)3 gave dinuclear complexes (L1)2RE(μ-Cl)(μ-η5:η1:η1-L1)RE(L1)[N(SiMe3)2]2 [RE = Sm (1e), Pr (1f)]; however, the reaction of L2H and [(Me3Si)2N]3Sm(μ-Cl)Li(THF)3 afforded (L2)2Sm[N(SiMe3)2]2 (2e). Results indicated that the ionic radius of rare-earth metal and subtle change in the ligands have substantial effects on the structure and bonding mode of complexes. The complexes showed a high catalytic activity for the ring-opening reaction of cyclohexene oxide with amines to afford various β-aminoalcohols under mild solvent-free conditions.
Heterogeneous ring-opening reactions and Knoevenagel condensation reactions with cobalt complexes: Effect of CoII versus CoIII states on catalysis
Kumar, Sushil,Gupta, Rajeev
, p. 843 - 852 (2020/06/26)
This work illustrates comparative catalytic performance of two sets of cobalt complexes within a common macrocyclic ligand environment: CoII complexes 1 and 2 versus CoIII complexes 3 and 4. All four cobalt complexes functioned as the heterogeneous catalysts for the ring-opening reactions of assorted epoxides as well as Knoevenagel condensation reactions of assorted aldehydes. Cobalt(II) complexes were noted to be the superior catalysts over cobalt(III) complexes for both types of organic transformations. The observed difference in the catalytic performance of two sets of cobalt complexes has been related to the kinetic differences between CoII versus CoIII ions. All four cobalt complexes display high catalytic efficiency and excellent reusability without any apparent loss in the catalytic performance.
Synthesis and structure of an air-stable bis(pentamethylcyclopentadienyl) zirconium pentafluorbezenesulfonate and its application in catalytic epoxide ring-opening reactions
Li, Ningbo,Wang, Lingxiao,Wang, Haojiang,Qiao, Jie,Zhao, Wenjie,Xu, Xinhua,Liang, Zhiwu
, p. 1033 - 1039 (2018/02/06)
An air-stable mononuclear complex of bis(pentamethylcyclopentadienyl) zirconium pentafluorbezenesulfonate was successfully synthesized by treating C6F5SO3Ag with [(CH3)5Cp]2ZrCl2, which showed the cationic uninuclear structure of [{(CH3)5Cp}2Zr(CH3CN)2(H2O)][OSO2C6F5]2·CH3CN (1) confirmed by the X-ray analysis. Complex 1 was also characterized by other techniques and found to have the good nature of air-stability, water tolerance, thermally-stability and strong Lewis-acidity. Moreover, the complex showed high catalytic activity and recyclability in catalytic epoxide ring-opening reactions by amines or alcohols. This catalytic system affords a simple and efficient approach for synthesis of β-amino alcohols or β-alkoxy alcohols.
Tetragonal versus hexagonal: Structure-dependent catalytic activity of Co/Zn bimetallic metal-organic frameworks
Pariyar, Anand,Asl, Hooman Yaghoobnejad,Choudhury, Amitava
, p. 9250 - 9257 (2016/09/28)
Tetragonal and hexagonal phases of monometallic Zn and bimetallic Co/Zn metal-organic frameworks (MOFs), with secondary building units (SBUs) containing a M3O (M = metal) cluster, were synthesized from identical constituents using a benzenetricarboxylate (BTC3-) linker that forms decorated 3,6- and 3,5-connected networks, respectively. There exist subtle differences between the SBUs; one of the metal atoms in the M3O cluster in the tetragonal phase has one dissociable DMF solvent molecule while that in the hexagonal phase has three. Connectivities between the SBUs form one-dimensional channels in both MOFs. These MOFs catalyze the chemoselective addition of amines to epoxides, giving exclusively β-hydroxyamine under heterogeneous conditions. A ring-opening reaction of a symmetrical epoxide showed that the hexagonal phase diastereoselectively yields trans-alcohol, exhibiting an exquisite model for structure-dependent activity.
Quaternary ammoniums and a cationic sodium complex as supramolecular catalysts in ring-opening of epoxides by amines
Thomas, Coralie,Brut, Sébastien,Bibal, Brigitte
, p. 1646 - 1650 (2014/02/14)
Supramolecular ionic organocatalysts and a metal-based catalyst were investigated in the ring-opening of epoxides by amines, without any artifice to enhance conversion (i.e., solvophobic effect, extended reaction time, heating, excess of amine, high catalyst loading). Different β-amino-alcohols were obtained in satisfying conversion (50-80%) in 24 h, under mild conditions.
N-Fluorobenzenaminium tetrafluoroborate generated in situ by aniline and Selectfluor as a reusable catalyst for the ring opening of epoxides with amines under microwave irradiation
Chauhan, Manmohan Singh,Yadav, Geeta Devi,Hussain, Firasat,Singh, Surendra
, p. 3945 - 3952 (2015/02/19)
The ring opening of epoxides with aromatic and aliphatic amines was carried out under solvent free conditions using N-fluorobenzenaminium tetrafluoroborate (2 mol%) generated in situ by the reaction of aniline and Selectfluor as a catalyst with microwave irradiation. Excellent yields of β-amino alcohols were obtained. The catalyst also results in the retention of the stereochemistry for the ring opening of enantiopure epoxide with amine. The catalyst was recovered and reused up to 4 cycles for the ring opening of cyclohexene oxide with aniline. This journal is
Three-dimensional {Co3+-Zn2+} and {Co 3+-Cd2+} networks originated from carboxylate-rich building blocks: Syntheses, structures, and heterogeneous catalysis
Kumar, Girijesh,Gupta, Rajeev
, p. 10773 - 10787 (2013/10/22)
The present work shows the utilization of Co3+ complexes appended with either para- or meta-arylcarboxylic acid groups as the molecular building blocks for the construction of three-dimensional {Co 3+-Zn2+} and {Co3+-Cd2+} heterobimetallic networks. The structural characterizations of these networks show several interesting features including well-defined pores and channels. These networks function as heterogeneous and reusable catalysts for the regio- and stereoselective ring-opening reactions of various epoxides and size-selective cyanation reactions of assorted aldehydes.
Efficient solvent-free aminolysis of epoxides under (C4H 12N2)2[BiCl6]Cl·H 2O catalysis
Lu, Hong-Fei,Sun, Lei-Lei,Le, Wen-Jun,Yang, Fei-Fei,Zhou, Jun-Tao,Gao, Yu-Hua
experimental part, p. 4267 - 4272 (2012/09/22)
An efficient and rapid procedure for ring opening of various epoxides with aromatic, aliphatic and heterocyclic amines is developed at room temperature under solvent-free conditions in the presence of (C4H 12N2)2[BiCl6]Cl·H 2O (1 mol %). This catalyst can be reused several times without losing of its activity.
In vivo antifilarial activity of some cyclic and acylic alcohols
Agarwal, Alka,Awasthi, Satish K.,Murthy
experimental part, p. 430 - 434 (2012/04/18)
The filarial nematodes, Wuchereria bancrofti, Brugia malayi, and Brugia timori are the causative agents of lymphatic filariasis. 2-Substituted propanol, cyclohexanol, and cyclooctanol compounds were evaluated for microfilaricidal and macrofilaricidal activity in vivo against Acanthocheilonema viteae and Litomosoides carinii in rodents. In the cyclohexanol series, 2-(piperidin-1-yl) cyclohexanol (2b) showed 88.9% macrofilaricidal activity against A. viteae in vivo, while cyclooctanol series, 2-(4- benzyl piperdin-1-yl) cyclooctanol (2f) showed 100% macrofilaricidal activity against A. viteae. Further, compounds 1-(furan-2-ylamino) ethanol (4a) and 1-(4-benzylpiperidin- 1-yl)-ethyl acetate (5b) showed 81.3% and 83.4% macrofilaricidal activity, respectively, against the same parasite. Interestingly, compounds 2f and 4a showed significant sterilization of female worms in A. viteae. However, these compounds were found inactive against L. carinii. Therefore, the new class of compounds appeared to have promising antifilarial activity.
