1892-20-2Relevant academic research and scientific papers
Triazinetriamine-derived porous organic polymer-supported copper nanoparticles (Cu-NPs@TzTa-POP): an efficient catalyst for the synthesis of: N -methylated products via CO2fixation and primary carbamates from alcohols and urea
Haque, Najirul,Biswas, Surajit,Basu, Priyanka,Haque Biswas, Imdadul,Khatun, Resmin,Khan, Aslam,Islam, Sk Manirul
supporting information, p. 15446 - 15458 (2020/10/22)
In recent times, carbon dioxide fixation has received much attention for its potential application as an abundant C1 source and a range of important fine chemicals can be manufactured via this fixation. Here, a copper nanoparticle-decorated porous organic polymer-based (Cu-NPs@TzTa-POP) material was prepared by a simple in situ process. The catalyst was characterized by various techniques such as UV-vis spectra, FTIR spectra, HR-TEM, PXRD, N2 adsorption-desorption, TG-DTA, XPS, and AAS analysis. The synthesized heterogeneous catalyst showed excellent activity in an atmospheric carbon dioxide fixation reaction to produce N-methylated products from aromatic/heterocyclic amines in the presence of polymethyl-hydrosiloxane (PMHS) as the reducing agent at 80 °C within 12 h of the reaction. Through this catalytic N-methylation reaction, we obtained 98% yield of the product with turnover frequency ranging from 18 to 42 h-1. The catalyst is also very stable for the formation of primary carbamates from alcohols using the eco-friendly carbonylating agent, urea. Diverse alcohols (such as benzylic alcohols, phenols, heterocyclic alcohols, as well as aliphatic alcohols) showed much acceptance to this catalytic reaction and produced moderate to excellent yields of the respective carbamate products under ambient reaction conditions. Moreover, Cu-NPs@TzTa-POP is effortlessly recyclable and reusable without the extensive loss of active copper metal centres for many catalytic rounds (up to six catalytic rounds were examined).
Nitro-[2,1-b]imidazopyran compounds and antibacterial uses thereof
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, (2008/06/13)
Methods, compounds and compositions are provided for inhibiting the growth of pathogenic microbes in vitro and of treatment of pathogenic bacterial infections, such as mycobacterial, Clostridium, Cryptosporidium and Helicobacter infections, in vivo using bicyclic nitroimidazole compounds of the formula (II): STR1 wherein R1 is hydrogen, halogen, loweralkyl, haloloweralkyl, cycloalkyl, heterocycle, substituted heterocycle and heterocyclicalkyl; X is oxygen, sulfur or NR2, where R2 is hydrogen, loweralkyl, aryl, cycloalkyl, heterocycle, substituted heterocycle, heterocyclicalkyl, COR3 or SO2 R4 CONR4 R5, where R3, R4 and R5 are independently selected from hydrogen, loweralkyl, aryl, alkylaryl, alkoxyalkyl, alkoxyaryl, alloxyalkoxyaryl, alkylheterocycle, and alkoxyheterocycle; n is 1, 2 or 3; Y and Z are independently selected from oxygen, CH2, CO, CR4 R5 or NR4, where R4 and R5 are as defined above; provided that when n is 2 or 3, the compounds of formula II can be additionally substituted as follows: STR2 wherein R6, R7, R8 and R9 are independently selected from hydrogen, loweralkyl, aryl, alkylaryl, alkoxyalkyl, alkoxyalkylaryl, alkoxyalkylheterocycle, alkylary2alkylaryl, alkylarylaryl, alkylcycloalkyl, alkoxyaryl, alkylheterocycle, and alkoxyheterocycle; and the pharmaceutically acceptable salts thereof.
