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1.
Jonali Goswami Rajiv L. Bezbaruah Amrit Goswami Naleen Borthakur 《Tetrahedron: Asymmetry》2002,12(24):3343-3348
β-Adrenoreceptor agonists (R)-(−)-denopamine (R)-1 and (R)-(−)-salmeterol (R)-2 have been prepared in good overall yield and high enantioselectivity through a biotransformative pathway. 相似文献
2.
Singh Amrit Singh Amritpal Amanjot Singh Kulvinder Singh Gurjaspreet Saroa Amandeep 《Structural chemistry》2021,32(3):1269-1278
Structural Chemistry - The nucleophilic aromatic substitution reactions of 4,6-dinitroisoindoline-1,3-dione with 1,2,3-triazole isomers, i.e., 1H-1,2,3-triazole and 2H-1,2,3-triazole, have been... 相似文献
3.
Ujwal Pratim Saikia Diganta BaruahPallab Pahari Manash Jyoti Borah Amrit GoswamiDilip Konwar 《Tetrahedron letters》2014
A mild and efficient methodology has been developed for the synthesis of spiro-1,3-oxazine derivatives by the microwave assisted cyclization of N-2-(1′-cyclohexenyl)ethyl-acetamides/benzamides. The reaction was catalyzed by in situ generated trimethylsilyl iodide and featured by its very short reaction time. The starting materials were easily obtained by the condensation of substituted acetic/benzoic acids with 2-(1′-cyclohexenyl)ethyl amine. 相似文献
4.
Crocetti Letizia Floresta Giuseppe Nazir Shabnam Vergelli Claudia Bhogal Amrit Biancalani Claudio Cesari Nicoletta Giovannoni Maria Paola Cilibrizzi Agostino 《Structural chemistry》2022,33(3):769-793
Structural Chemistry - We report here synthetic approaches to access new classes of small molecules based on three heterocyclic scaffolds, i.e. 3,7-dihydropyrimido[4,5-d]pyridazine-4,8-dione,... 相似文献
5.
A. P. Karande A. K. Fulzele Amrit Prakash Md. Afzal J. P. Panakkal H. S. Kamath 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(2):451-455
Neutron Well Coincidence Counting has been explored as a non destructive assay technique for determining the percentage of
PuO2 in blended mixture of UO2 and PuO2 powders. The method has been applied to MOX blends having PuO2 content varying from 0.4 to 44% for both thermal and fast reactors. The use of Neutron Well Coincidence Counting technique
is validated as a process control step for determining PuO2 content in the fabrication of MOX fuel by comparing it with chemical analysis of sintered pellets. It has been used at Advanced
Fuel fabrication Facility, Bhabha Atomic Research Centre, Tarapur during the manufacture of MOX fuel of various types for
thermal and fast reactors. 相似文献
6.
Summary A new tri-cavity decaaza macrocycle (TCM) has been synthesised by the condensation of tetra(aminopropyl)-cyclam with diethanolamine. The new macrocyclic ligand forms tri-nuclear complexes, [Cu3(TCM)(H2O)2]-(ClO4)6 and [Ni3(TCM)(H2O)2](ClO4)6. 相似文献
7.
Ai‐Xin Zhu Qing‐Yuan Yang Soumya Mukherjee Amrit Kumar Cheng‐Hua Deng Andrey A. Bezrukov Mohana Shivanna Michael J. Zaworotko 《Angewandte Chemie (International ed. in English)》2019,58(50):18212-18217
Coordination networks that reversibly switch between closed and open phases are of topical interest since their stepped isotherms can offer higher working capacities for gas‐storage applications than the related rigid porous coordination networks. To be of practical utility, the pressures at which switching occurs, the gate‐opening and gate‐closing pressures, must lie between the storage and delivery pressures. Here we study the effect of linker substitution to fine‐tune gate‐opening and gate‐closing pressure. Specifically, three variants of a previously reported pcu ‐topology MOF, X‐pcu‐5‐Zn , have been prepared: X‐pcu‐6‐Zn , 6 =1,2‐bis(4‐pyridyl)ethane (bpe), X‐pcu‐7‐Zn , 7 =1,2‐bis(4‐pyridyl)acetylene (bpa), and X‐pcu‐8‐Zn , 8 =4,4′‐azopyridine (apy). Each exhibited switching isotherms but at different gate‐opening pressures. The N2, CO2, C2H2, and C2H4 adsorption isotherms consistently indicated that the most flexible dipyridyl organic linker, 6 , afforded lower gate‐opening and gate‐closing pressures. This simple design principle enables a rational control of the switching behavior in adsorbent materials. 相似文献
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Efficient CO2 Removal for Ultra‐Pure CO Production by Two Hybrid Ultramicroporous Materials 下载免费PDF全文
Dr. Kai‐Jie Chen Dr. Qing‐Yuan Yang Dr. Susan Sen Dr. David G. Madden Amrit Kumar Dr. Tony Pham Katherine A. Forrest Dr. Nobuhiko Hosono Prof. Dr. Brian Space Prof. Dr. Susumu Kitagawa Prof. Dr. Michael J. Zaworotko 《Angewandte Chemie (International ed. in English)》2018,57(13):3332-3336
Removal of CO2 from CO gas mixtures is a necessary but challenging step during production of ultra‐pure CO as processed from either steam reforming of hydrocarbons or CO2 reduction. Herein, two hybrid ultramicroporous materials (HUMs), SIFSIX‐3‐Ni and TIFSIX‐2‐Cu‐i , which are known to exhibit strong affinity for CO2, were examined with respect to their performance for this separation. The single‐gas CO sorption isotherms of these HUMs were measured for the first time and are indicative of weak affinity for CO and benchmark CO2/CO selectivity (>4000 for SIFSIX‐3‐Ni ). This prompted us to conduct dynamic breakthrough experiments and compare performance with other porous materials. Ultra‐pure CO (99.99 %) was thereby obtained from CO gas mixtures containing both trace (1 %) and bulk (50 %) levels of CO2 in a one‐step physisorption‐based separation process. 相似文献
10.
Temperature‐ and Pressure‐Dependent Kinetics of CH2OO + CH3COCH3 and CH2OO + CH3CHO: Direct Measurements and Theoretical Analysis 下载免费PDF全文
Rehab M. I. Elsamra Amrit Jalan Zachary J. Buras Joshua E. Middaugh William H. Green 《国际化学动力学杂志》2016,48(8):474-488
The rate coefficients of the gas‐phase reactions CH2OO + CH3COCH3 and CH2OO + CH3CHO have been experimentally determined from 298–500 K and 4–50 Torr using pulsed laser photolysis with multiple‐pass UV absorption at 375 nm, and products were detected using photoionization mass spectrometry at 10.5 eV. The CH2OO + CH3CHO reaction's rate coefficient is ~4 times faster over the temperature 298–500 K range studied here. Both reactions have negative temperature dependence. The T dependence of both reactions was captured in simple Arrhenius expressions: The rate of the reactions of CH2OO with carbonyl compounds at room temperature is two orders of magnitude higher than that reported previously for the reaction with alkenes, but the A factors are of the same order of magnitude. Theoretical analysis of the entrance channel reveals that the inner 1,3‐cycloaddition transition state is rate limiting at normal temperatures. Predicted rate‐coefficients (RCCSD(T)‐F12a/cc‐pVTZ‐F12//B3LYP/MG3S level of theory) in the low‐pressure limit accurately reproduce the experimentally observed temperature dependence. The calculations only qualitatively reproduce the A factors and the relative reactivity between CH3CHO and CH3COCH3. The rate coefficients are weakly pressure dependent, within the uncertainties of the current measurements. The predicted major products are not detectable with our photoionization source, but heavier species yielding ions with masses m/z = 104 and 89 are observed as products from the reaction of CH2OO with CH3COCH3. The yield of m/z = 89 exhibits positive pressure dependence that appears to have already reached a high‐pressure limit by 25 Torr. 相似文献