6302-53-0Relevant academic research and scientific papers
Cu(II) immobilized on Fe3O4@Agarose nanomagnetic catalyst functionalized with ethanolamine phosphate–salicylaldehyde schiff base: A magnetically reusable nanocatalyst for preparation of 2-substituted imidazolines, oxazolines, and thiazolines
Zarei, Zeinab,Akhlaghinia, Batool
, p. 170 - 191 (2018/02/17)
Herein we synthesized Cu(II) immobilized on Fe 3 O 4 @Agarose functionalized with ethanolamine phosphate–salicylaldehyde Schiff base (Fe 3 O 4 @Agarose/SAEPH 2 /Cu(II)) as a new and cost-effective nanomagnetic catalyst. The nanomagnetic catalyst was characterized by FT- IR, XRD, VSM, SEM- EDX, TEM, TGA, and ICP techniques and it was found that the particles were about 9–25 nm in size and spherical with entrapment of the Fe 3 O 4 particles in the hollow pore structure of the agarose. The prepared nanomagnetic catalyst showed excellent activity for preparation of 2-substituted imidazolines, oxazolines, and thiazolines. The catalyst is easy to prepare and exhibits higher catalytic activity than some commercially available copper sources. More importantly, this nanomagnetic catalyst can be easily recovered by using a permanent magnet and reused for at least seven cycles without significant deactivation.
Synthesis of benzimidazole and quinoxaline derivatives using reusable sulfonated rice husk ash (RHA-SO3H) as a green and efficient solid acid catalyst
Shamsi-Sani, Mahnaz,Shirini, Farhad,Abedini, Masoumeh,Seddighi, Mohadeseh
, p. 1091 - 1099 (2016/04/26)
In this work, a simple, rapid and efficient method for the preparation of benzimidazoles and quinoxalines from the condensation of o-phenylene diamines with aldehydes and/or 1,2-dicarbonyl compounds in the presence of sulfonated rice husk ash (RHA-SO3H) as an efficient green catalyst is reported. RHA-SO3H can be easily prepared using a readily available organic compound by simple modification of rice husk ash. All reactions are performed under mild reaction conditions with high to excellent yields. The method is applicable to aromatic, unsaturated and hetero aromatic aldehydes. The advantages of this method are short reaction times, milder conditions, easy work-up, solvent-free conditions and catalyst reusability.
Ruthenium(II) carbonyl complexes containing pyridoxal thiosemicarbazone and trans-bis(triphenylphosphine/arsine): Synthesis, structure and their recyclable catalysis of nitriles to amides and synthesis of imidazolines
Manikandan, Rajendran,Anitha, Panneerselvam,Prakash, Govindan,Vijayan, Paranthaman,Viswanathamurthi, Periasamy,Butcher, Ray Jay,Malecki, Jan Grzegorz
, p. 312 - 324 (2015/01/30)
Pyridoxal N(4)-substituted thisemicarbazone hydrochloride ligands (L1-3) were synthesized and reacted with the ruthenium(II) starting complexes [RuHCl(CO)(EPh3)3] (EP or As). The resulting complexes [Ru(CO)(L1-3)(EPh3)2] (1-6) were characterized by elemental analyses and spectroscopic techniques. The molecular structure of complex 5 was identified by means of single crystal X-ray diffraction analysis. The catalytic activity of the new complexes was evaluated for the selective hydration of nitriles to primary amides and also the condensation of nitriles with ethylenediamine under solvent free conditions. The processes were operative with aromatic, heteroaromatic and aliphatic nitriles, and tolerated several substitutional groups. The studies on the effect of substitution over thiosemicarbazone, reaction time, temperature, solvent and catalyst loading were carried out in order to find the best catalyst in this series of complexes and favourable reaction conditions. A probable mechanism for both the catalytic reactions of nitrile has also been proposed. The catalyst was recovered and recycled in the hydration of nitriles for five times without any significant loss of its activity.
Thermally triggered solid-state single-crystal-to-single-crystal structural transformation accompanies property changes
Li, Quan-Quan,Ren, Chun-Yan,Huang, Yang-Yang,Li, Jian-Li,Liu, Ping,Liu, Bin,Liu, Yang,Wang, Yao-Yu
supporting information, p. 4703 - 4711 (2015/03/18)
The 1D complex [(CuL0.5H2O)·H2O]n (1) (H4 L = 2,2′-bipyridine-3,3′ ,6,6′-tetracarboxylic acid) undergoes an irreversible thermally triggered single-crystal-to-single-crystal (SCSC) transformation to produce the 3D anhydrous complex [CuL0.5]n (2). This SCSC structural transformation was confirmed by single-crystal X-ray diffraction analysis, thermogravimetric (TG) analysis, powder X-ray diffraction (PXRD) patterns, variable-temperature powder X-ray diffraction (VT-PXRD) patterns, and IR spectroscopy. Structural analyses reveal that in complex 2, though the initial 1D chain is still retained as in complex 1, accompanied with the Cu-bound H2O removed and new O(carboxyl)-Cu bond forming, the coordination geometries around the CuII ions vary from a distorted trigonal bipyramid to a distorted square pyramid. With the drastic structural transition, significant property changes are observed. Magnetic analyses show prominent changes from antiferromagnetism to weak ferromagnetism due to the new formed Cu1-O-C-O-Cu4 bridge. The catalytic results demonstrate that, even though both solid-state materials present high catalytic activity for the synthesis of 2-imidazolines derivatives and can be reused, the activation temperature of complex 1 is higher than that of complex 2. In addition, a possible pathway for the SCSC structural transformations is proposed.
Semi-empirical computation on mechanism of imidazolines and benzimidazoles synthesis and their QSAR studies
Hazarika, Swapnali,Konwar, Dilip,Bora, Manas Jyoti
, p. 5073 - 5078 (2015/01/09)
A green, mild and anaerobic synthesis of imidazolines and benzimidazoles from aldehydes and diamines using I2/KI/K2CO3/H2O system has been investigated by semi-empirical methods. The observed efficient direction of the above synthesis has been modeled from a comparison of the energies of four possible transition states arising from mono and di additions of iodines in the configured molecules. In the reaction I1 B is the most favorable transition state [TS] which is shown to be 20 Kcal/mol by PM3 analyses. The resulting trends of relative transition states energies are in excellent agreement with the experimental observations. Also, the bond order, bond length, heat of formation is in good agreement to the formation of product B. In order to establish the suitable mechanism of the reaction a quantitative structure activity relationship analysis has been made using hydrophobicity as the molecular descriptor. In this analysis the values of refractivity, polarizability, hydration energy, electron affinity, ionization potential and dipole moment of the compounds have been correlated with their hydrophobicity which has been taken as the molecular property.
Pd-catalyzed N-arylation of 2-imidazolines provides convenient access to selective cyclooxygenase-2 inhibitors
Krasavin, Mikhail
, p. 235 - 239 (2013/07/26)
The re-emergence, in the recent years, of cyclooxygenase as a biological target in therapeutic areas other than inflammation is likely to require new optimized leads, particularly suited for the requirements of specific drug development programs. We devel
Microwave-assisted cascade cycloaddition for C-N bond formation: An approach to the construction of 1,4,5,6-tetrahydropyrimidine and 2-imidazoline derivatives
An, Shujuan,Yin, Bing,Liu, Ping,Li, Xiangnan,Li, Chen,Li, Jianli,Shi, Zhen
, p. 2525 - 2532 (2013/09/24)
An efficient strategy for the synthesis of various 1,4,5,6- tetrahydropyrimidine and 2-imidazoline derivatives has been reported. The reactions proceeded from nitriles with ethylenediamine or 1,3-diaminopropane via cascade cycloaddition in the presence of CuL2 (L = 2-hydroxy-2-phenylacetate) to afford the corresponding 1,4,5,6- tetrahydropyrimidine or 2-imidazoline derivatives under reflux conditions or microwave irradiation in excellent yields.
Palladium-catalyzed multicomponent synthesis of 2-aryl-2-imidazolines from aryl halides and diamines
Geden, Joanna V.,Pancholi, Alpa K.,Shipman, Michael
, p. 4158 - 4164 (2013/05/22)
An efficient palladium-catalyzed three-component reaction that combines aryl halides, isocyanides, and diamines provides access to 2-aryl-2-imidazolines in yields up to 96%. Through variation of the diamine component, the reaction can be extended to the s
Trichloroisocyanuric acid as an efficient homogeneous catalyst for the chemoselective synthesis of 2-substituted oxazolines, imidazolines and thiazolines under solvent-free condition
Hojati, Seyedeh Fatemeh,Nezhadhoseiny, Seyede Atefe
, p. 1181 - 1189,9 (2020/09/14)
Trichloroisocyanuric acid, as a commercially available and inexpensive catalyst, was used in a new, facile and efficient procedure for the synthesis of 2-oxazolines, 2-imidazolines and 2-thiazolines through the reaction of nitriles with 2-aminoethanol, ethylenediamine or 2-aminoethanethiol under solvent-free conditions.
Novel diversely substituted 1-heteroaryl-2-imidazolines for fragment-based drug discovery
Krasavin, Mikhail
scheme or table, p. 2876 - 2880 (2012/07/28)
A palladium-catalyzed Buchwald-Hartwig arylation protocol has been applied to achieve high-yielding N-heteroarylation of a diverse set of privileged 2-imidazolines. The resulting compounds are of interest as a novel type of molecular tool for fragment-bas
