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991.
Samaresh Layek Bhumika Agrahari Rakesh Ganguly Parthasarathi Das Devendra D. Pathak 《应用有机金属化学》2020,34(3):e5414
Benzoylhydrazone Schiff base–ligated three new ONO pincer–type palladium(II) complexes, [(PdL1(PPh3)] ( 1 ), [(PdL2(PPh3)] ( 2 ), and [(PdL3(PPh3)] ( 3 ), were synthesized by the reaction of the respective ligand, N-(2-hydroxybenzylidene)benzohydrazide (HL1), N-(2-hydroxy-3-methoxybenzylidene)benzohydrazide (HL2), or N-(5-bromo-2-hydroxybenzylidene) benzohydrazide (HL3), with Pd(OAc)2 and PPh3 in methanol and isolated as air-stable reddish-orange crystalline solids in high yields (78%–83%). All three complexes were fully characterized by elemental analysis, Fourier-transform infrared spectroscopy, UV–Visible, 1H nuclear magnetic resonance (NMR), 13C{1H} NMR, and 31P{1H} NMR spectroscopic studies. The molecular structure of all three complexes was established unambiguously by single-crystal X-ray diffraction studies which revealed a distorted square planar geometry of all three complexes. The ONO pincer–type ligands occupied three coordination sites at the palladium, while the fourth site is occupied by the monodentate triphenylphosphine ligand. The catalytic potential of all three complexes was explored in the carbonylative Suzuki coupling of aryl bromides and iodides with arylboronic acids to yield biaryl ketones, using CHCl3 as the source of carbonyl. The reported protocol is convenient and safe as it obviates the use of carbon monoxide (CO) balloons or pressured CO reactors which are otherwise needed for the carbonylation reactions. The methodology has been successfully applied to the synthesis of two antineoplastic drugs, namely, phenstatin and naphthylphenstatin, in good yields (81% and 85%, respectively). Under the optimized reaction conditions, complex 2 exhibited the best catalytic activity in the carbonylative Suzuki couplings. The reported catalysts have wide reaction scope with good functional group tolerance. All catalysts could be retrieved from the reaction after completion and recycled up to three times with insignificant loss in the catalytic activity. 相似文献
992.
Structural Chemistry - Ab initio computation is performed on the binuclear sandwich complexes, M2(η5-Sb5)2. Eclipsed and staggered conformations are generated due to the η5 mode of... 相似文献
993.
Begum Mahbuba Khan Rahat Roy Dhiman Kumer Habib Md. Ahosan Rashid Md. Bazlar Naher Kamrun Islam Mohammad Amirul Tamim Umma Das Sudeb Chandra Al Mamun S. M. Mostafa Hossain Syed Mohammod 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):239-252
Journal of Radioanalytical and Nuclear Chemistry - Geochemical characterization of Shahbazpur structure (Bengal Foredeep) in terms of elemental abundances obtained from INAA are presented by... 相似文献
994.
Liu Shang-Hao Yu Chang-Fei Das Mitali 《Journal of Thermal Analysis and Calorimetry》2020,140(5):2325-2336
Journal of Thermal Analysis and Calorimetry - Severe fire and explosions are frequent phenomena during handling of organic peroxides that are promoted supremely by conditions such as chemical... 相似文献
995.
Monojit Das Bairagya Ryan J. Bujol Prof. Noémie Elgrishi 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(18):3991-4000
Development of highly active molecular electrocatalysts for fuel-forming reactions has relied heavily on understanding mechanistic aspects of the electrochemical transformations. Careful fine-tuning of the ligand environment oriented mechanistic pathways towards higher activity and optimal product distribution for several catalysts. Unfortunately, many catalysts deactivate in bulk electrolysis conditions, diminishing the impact of the plethora of highly tuned molecular electrocatalytic systems. This Minireview covers classical and emerging methods developed to circumvent catalyst deactivation and degradation, with an emphasis on successes with molecular electrocatalysts. 相似文献
996.
Majumder Ratan Kumar Das Sudeb Chandra Rasul Md. Golam Khalil Mohammad Ibrahim Dina Nafisa Tamannaya Kabir Mohammad Zafrul Deeba Farah Rajib Mohammad 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(1):265-277
Journal of Radioanalytical and Nuclear Chemistry - The study investigates the measurement of radon concentration in soils and rocks as a natural tracer for exploring uranium mineralization, first... 相似文献
997.
A new dioxo-molybdenum (VI) complex supported on functionalized Merrifield resin ( MR-Mo ) has been synthesized and characterized by elemental, scanning electron mcroscopy, energy-dispersive X-ray analysis, TGA, Brunauer–Emmett–Teller method, powder-X-ray diffraction, Fourier transform infrared, X-ray photoelectron spectroscopy and DRS–UV–vis analysis. The virgin Merrifield resin ( MR ) was functionalized by carbonylation followed by Schiff base formation with ethanolamine ( MR-SB ). Experimental data showed that the Schiff base coordinated with the MoO22+ moiety via O- and N-atoms. The catalytic activity of MR-Mo was explored under solventless conditions toward the oxidation of organic sulfides and alcohols using 30% aqueous H2O2 as oxidant. The oxidation reactions were conducted under microwave and conventional methods. The microwave-assisted oxidation reactions were found to be many times faster than the conventional methods. The oxidation reactions were selective and formed sulfoxides or aldehydes as the sole product with superior TOF values among the molybdenum (VI)-based complexes. Besides these, the MR-Mo was purely heterogeneous in nature and can be recycled for at least five reaction cycles without the loss of catalytic efficiency and product selectivity. 相似文献
998.
A RhIII‐catalyzed strategy was developed for the rapid construction of highly substituted 2‐pyridone scaffolds using α,β‐unsaturated oximes and fluorinated diazomalonate. The reaction proceeds through direct, site‐selective alkylation based on migratory insertion and subsequent cyclocondensation. A wide substrate scope with different functional groups was explored. The requirement of fluorinated diazomalonate was explored for this transformation. The developed methodology was further extended with the synthesis of the bioactive compound. 相似文献
999.
Das Subhrajit Vasudevan Sivaprakasam 《Journal of Radioanalytical and Nuclear Chemistry》2021,329(2):633-646
Journal of Radioanalytical and Nuclear Chemistry - Radionuclides dating have been applied in the chronological series of sediment core recovered from Satopanth Tal to estimate the sedimentation... 相似文献
1000.
Jena Sudipta Ray Asit Sahoo Ambika Das Prabhat Kumar Champati Bibhuti Bhusan Nayak Sanghamitra Panda Pratap Chandra 《Chemistry of Natural Compounds》2022,58(3):550-552
Chemistry of Natural Compounds - 相似文献