Morpholine

About: Morpholine is a research topic. Over the lifetime, 5411 publications have been published within this topic receiving 51063 citations. The topic is also known as: diethylene imidoxide & diethylene oximide.

Studies on the solvent extraction of metal dithiocarbamates

Abstract: Studies on the solvent extraction of morpholine dithiocarbamic acid complexes of divalent metal ions Mn, Fe, Co, Ni, Cu, Zn, Pb, Cd, Hg, and Sn were carried out, and the extraction constants and the overall stability constants were determined. The stability constants of complexes of Cu(II) formed with various substituted dithiocarbamic acids, showed a variation of the stability constants with the basicity of the nitrogen and sulfur atoms in the reagents.

Novel stimuli-responsive hydrogels derived from morpholine: synthesis, characterization and absorption uptake of textile azo dye

Abstract: A new cationic monomer methacrylamido-4-(2-aminoethyl)morpholine, (MAEM) derived from morpholine was synthesized in a single step and characterized by FTIR, 1H and 13C NMR analyses. Through free radical aqueous polymerization, novel copolymeric hydrogels have been prepared successfully using methacrylamido-4-(2-aminoethyl)morpholine and acrylamide (Aam) as monomers. Later on SEM, FTIR, elemental analysis and TG instruments were used to characterize the obtained poly(acrylamide-co-methacrylamido-4-(2-aminoethyl)morpholine), poly(Aam-c-MAEM), hydrogels. Poly(Aam-c-MAEM) hydrogels were tested for swelling, diffusion and uptake of reactive orange, RO, anionic dye. In this regard, various adsorption kinetics and isotherm models as well as operation parameters were systematically examined and discussed in detail in relation to adsorption uptake such as pH of media, comonomer composition, adsorbent dosage, temperature, initial dye concentration and contact time. The description of adsorption process of RO on hydrogels was consistent with the pseudo-second-order model followed by Elovich and pseudo-first-order. The best fitting adsorption model was selected on the basis of R 2, in the order of: Temkin > D-R > Langmuir > Freundlich isotherm. The results obtained in this study demonstrate that poly(Aam-c-MAEM) hydrogels provide an excellent advantage for application of this hydrogel system in the removal of anionic textile dyes from wastewater.

2,3-Dihydrospiro[1H-4- and 5-azabenzimidazole-2,1′ -cyclohexane] ( = Spiro[cyclohexane-1,2′(3′H)-1′H-imidazo[4,5-b]pyridine] and Spiro[cyclohexane-1,2′(3′H)-1′H-imidazo[4, 5-c]pyridine]): Reactions with Nucleophiles

Abstract: The readily available title compounds 4a and 24 react with N-, O-, S-, and C-nucleophiles in presence of MnO2 to give the corresponding mono- or disubstituted 2H-azabenzimidazoles ( = azaisobenzimidazoles), e.g., 11–18 and 26a–h, respectively, or 2,3-dihydro-1H-azabenzimidazoles ( = dihydro-azabenzimidazoles) such as 9 and 10 and 27 and 28, respectively, by a 1, 4- or 1,6-Michael addition (Schemes 2 and 4). The bromo-dihydro-1H-azabenzimidazole 4b lost the Br-atom when treated with piperidine or morpholine yielding the corresponding disubstituted 2H-azabenzimidazole 21 (Scheme 3). Reductive ring opening of the substituted spiro compounds leads to mono- and disubstituted diaminopyridines which are intermediates for fused pyridine ring systems with substituents often not available by conventional routes and of potential pharmaceutical interest (see 32–37). E.g., starting from 4a, a three-step synthesis of the analgesic flupirtine maleate (= ethyl {2-amino-6-[(4-fluorobenzyl)amino]pyridin-3-yl}carbamate maleate = Katadolon®; 39) and of its non-fluorinated derivative D-7195 is described. Its analogue 40 was similarly made from the spiro compound 24.