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Lalmohan Jhulki Rakesh Purkait HemantaK. Kisan Valerio Bertolasi AnvarhuseinA. Isab Chittaranjan Sinha Joydev Dinda 《应用有机金属化学》2020,34(8):e5673
Starting from proligand 1-methyl-2-(phenyl)imidazo[1,5-a]pyridine-2-iumchloride ( 1 .HCl), 1-methyl-2-(phenyl)imidazo[1,5-a]pyridine silver(I)chloride, ( 2 ) has been prepared. Synthesis, structures and photophysical properties of (2,2/−bipyridyl)-1-methyl-2-(phenyl)imidazo[1,5-a]pyridinesilver(I)hexaflurophosphate, ( 3 ), 1-methyl-2-(phenyl)imidazo[1,5-a]pyridinesilver(I)carbazolate, ( 4 ) and 1-methyl-2-(phenyl)imidazo[1,5-a]pyridinegold(I)carbazolate, ( 5 ) are focused. Herein we have first reported the NHC-Ag-(bpy/carbazole). All the complexes have been characterized by elemental analysis, various spectroscopic studies and finally screened for luminescent properties. All the complexes are strongly emissive. Solid state structures of 2 , 3 , 4 and 5 have been determined by X-ray diffraction studies. Conventionally, complex 2 adopts linear geometry whereas complex 3 embraces triangular planar geometry around Ag; complex 4 and 5 clinches linear geometry around Ag/Au. All the complexes absorb light within 275–343 nm. Complex 3 is luminous at ~407 mn, whereas complex 4 and 5 luminous at ~360 nm having short life time 1.00–6.97 ns. The quantum yield (Φem) of the complexes varies 0.106–0.186. It is expected variation of luminescence arises due to change of metal and the chromophore (bpy/carbazole). Density Functional Theory (DFT) and Temparature Dependent Density Functional Theory (TDDFT) calculations were performed to verify crystallographically derived parameters and to calculate the UV–Vis properties of the ground state as well as of the first excited state of the complexes. 相似文献
124.
Moumita Maiti Susanta Lahiri B. S. Tomar 《Journal of Radioanalytical and Nuclear Chemistry》2012,291(2):427-432
149Gd was produced from the 12C induced reaction on natural praseodymium target. No-carrier-added (nca) 149Gd was separated from the bulk target matrix by liquid–liquid extraction (LLX) using cation exchanger di-(2-ethylhexyl)phosphoric
acid (HDEHP) dissolved in cyclohexane. High separation factor of 2,450 was achieved at the optimal experimental condition
when 1% HDEHP and 0.1 M HCl were used as organic and aqueous phases respectively. The result was also compared with the previous
reports. 相似文献
125.
Subhashree P. DashSagarika Pasayat SaswatiHirak R. Dash Surajit DasRay J. Butcher Rupam Dinda 《Polyhedron》2012,31(1):524-529
Some new oxovanadium(V) complexes, [VOL1-3(OEt)(EtOH)] (1-3), have been reported, which were obtained from the reaction of the Schiff bases H2L1-3 (where H2L1 = the salicylhydrazone of diacetyl monoxime; H2L2 = the 4-methoxy salicylhydrazone of diacetyl monoxime and H2L3 = the 4-hydroxy salicylhydrazone of diacetyl monoxime) with VO(acac)2 in a 1:1 molar ratio. Three 4-R-aroylhydrazoneoximes (V) have been used as ligands in the present study, differing in the inductive effect of the substituent R (R = H, OCH3 and OH), in order to observe their influence, if any, on the redox potentials and biological activity of the complexes. All the synthesized ligands and metal complexes were successfully characterized by elemental analysis, IR, UV-Vis and NMR spectroscopy. An X-ray diffraction study of [VOL1(OEt)(EtOH)] (1) reveals that the metal center has a distorted octahedral O5N coordination sphere, where the O,N,O donor ligand and the ethoxo group constitute a satisfactory O3N basal plane. Cyclic voltammetry of the complexes show a quasi-reversible cyclic voltammetric response in the potential range 0.29-0.36 V involving a single electron V(V)-V(IV) reduction. The complexes have also been screened for their antibacterial activity against Escherichia coli, Bacillus, Proteus and Klebsiella. Minimum inhibitory concentrations of these complexes and the antibacterial activities indicate compound 1 as the potential lead molecule for drug design. 相似文献
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127.
Amongst various radionuclides of molybdenum, 90Mo and 99Mo have suitable β energy for clinical uses. In this paper we report separation of 99Mo from 99Mo-99mTc equilibrium mixture. The liquid–liquid extraction technique has been employed using trioctylamine (TOA) diluted in cyclohexane
as organic phase and HCl as aqueous phase. At 10−5 M HCl and 0.5 M TOA concentration 99mTc quantitatively transferred to the organic phase leaving 99Mo in the aqueous phase. The developed separation method is efficient and provides very high separation factor. 相似文献
128.
Urvashi Gangal Monika Srivastava Susanta K. Sen Gupta 《Plasma Chemistry and Plasma Processing》2010,30(2):299-309
A study of scavenging effects of iso-propanol, n-propanol, n-butanol and acetone on H• radicals, precursors for nonfaradaic products of anodic contact glow discharge electrolysis (CGDE) in aqueous media, has
been carried out. A kinetic analysis of the competing reactions of H• with different species in the system leads to a primary yield of 9.8 mol (mol electron)−1 each of H• and OH• radicals in the liquid-phase reaction zone of anodic CGDE. The method is considerably more convenient to apply than those
reported earlier based on the use of OH• scavengers. 相似文献
129.
Closed-shell contacts between two copper(I) ions are expected to be repulsive. However, such contacts are quite frequent and are well documented. Crystallographic characterization of such contacts in unsupported and bridged multinuclear copper(I) complexes has repeatedly invited debates on the existence of cuprophilicity. Recent developments in the application of Bader's theory of atoms-in-molecules (AIM) to systems in which weak hydrogen bonds are involved suggests that the copper(I)-copper(I) contacts would benefit from a similar analysis. Thus the nature of electron-density distributions in copper(I) dimers that are unsupported, and those that are bridged, have been examined. A comparison of complexes that are dimers of symmetrical monomers and those that are dimers of two copper(I) monomers with different coordination spheres has also been made. AIM analysis shows that a bond critical point (BCP) between two Cu atoms is present in most cases. The nature of the BCP in terms of the electron density, ρ, and its Laplacian is quite similar to the nature of critical points observed in hydrogen bonds in the same systems. The ρ is inversely correlated to Cu-Cu distance. It is higher in asymmetrical systems than what is observed in corresponding symmetrical systems. By examining the ratio of the local electron potential-energy density (V(c)) to the kinetic energy density (G(c)), |V(c)|/G(c) at the critical point suggests that these interactions are not perfectly ionic but have some shared nature. Thus an analysis of critical points by using AIM theory points to the presence of an attractive metallophilic interaction similar to other well-documented weak interactions like hydrogen bonding. 相似文献
130.
A new iridoid, shanzhiol (1), was isolated from the aerial parts of Mussaenda roxburghii. The structure was established by spectroscopic (including 2D NMR) and chemical methods. Shanzhiol (1) showed mild antibacterial activity against both Staphylococcus aureus and Escherichia coli with a MIC of 100 microg/mL by the broth dilution method. 相似文献