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1.
Vadapalli Chandrasekhar Viswanathan Baskar Ramamoorthy Boomishankar Selvarajan Nagendran 《Phosphorus, sulfur, and silicon and the related elements》2013,188(4-5):699-701
The reactions of n-butyl stannonic acid with(PhO) 2 P(O)H leads to the formation of a hexameric tin cage [{(n-BuSn) 3 (PhO) 3 O} 2 {HPO 3 } 4 ].This reaction involves an in situ P─O bond cleavage and the generation of a [HPO 3 ] 2? ion. A direct reaction of six equivalents of n-BuSnO(OH) acid with six equivalents of C 6 H 5 OH and four equivalents of H 3 PO 3 also leads to the formation of same cage structure. A tetranuclear organooxotin cage[(PhCH 2 ) 2 Sn 2 O(O 2 P(OH)-t-Bu) 4 ] 2 has been assembled by debenzylation involving the reaction of (PhCH 2 ) 2 SnCl 2 ,(PhCH 2 ) 2 SnO·H 2 O or (PhCH 2 ) 3 SnCl with two equivalents of t-BuP(O)OH 2 . A half-cage intermediate [(PhCH 2 ) 2 Sn 2 O(O 2 P(OH)-t-Bu) 4 ] has been detected. New organotin cations of the type [n-Bu 2 Sn(H 2 O) 4 ] 2+[2,5-Me 2 -C 6 H 3 SO 3 ]? 2 and {[n-Bu 2 Sn(H 2 O) 3 LSn(H 2 O) 3 (n-Bu) 2 ] 2+[1,5-(SO 3 ) 2 -C 10 H 6 ] 2?} have been obtained in the reactions of n-Bu 2 SnO or (n-Bu 3 Sn) 3 O with 2,5-dimethyl sulfonic acid and 1,5-naphthalene disulfonic acid respectively. These organotin cations form interesting supramolecular structures in the solid state as a result of O─H─···O hydrogen bonding. 相似文献
2.
Can Low‐Valent Germanium Chemistry Be Practiced Under Ambient Conditions? A Tale of a Water‐Stable Yet Reactive Germylene Monochloride Complex 下载免费PDF全文
Chandan Kumar Jha Surendar Karwasara Dr. Selvarajan Nagendran 《Chemistry (Weinheim an der Bergstrasse, Germany)》2014,20(33):10240-10244
A germylene monochloride complex ((DPM)GeCl, 1 ) that is water stable was isolated for the first time. Interestingly, it reacts with cesium fluoride under ambient conditions (non‐inert atmosphere and water‐containing solvent) to afford water stable germylene monofluoride complex ((DPM)GeF, 2 ). Due to the usage of DPM (dipyrrinate) ligand, germylene monohalides 1 and 2 show fluorescence in the visible region at 555 and 538 nm, respectively. Compounds 1 and 2 are the first fluorescent germylene complexes and were characterized by multinuclear NMR spectroscopy. The structure of compound 1 was also proved by single crystal X‐ray diffraction studies. 相似文献
3.
V. Chandrasekhar S. Nagendran S. Kingsley V. Krishnan R. Boomishankar 《Journal of Chemical Sciences》2000,112(3):171-178
This article presents a brief overview of different kinds of silanols and the important reactions of N-bonded silanetriols.
The synthesis and characterization of silanediols containing Si-N and Si-C bonds, (2,4,6-Me3C6H2)N(SiMe3)Si(Me)(OH)2 (1e) is described. 1e shows a polymeric crinkled tape type of structure due to extensive intermolecular hydrogen bonding.
We also describe the formation of a neutral copper(II) complex derived from the reaction of CuCl2 with (O)P(3,5-Me2Pz)3 where the ligand undergoes a facile P-N bond cleavage and functions as an N2O type of tridentate ligand. 相似文献
4.
Sarish S Nembenna S Nagendran S Roesky HW Pal A Herbst-Irmer R Ringe A Magull J 《Inorganic chemistry》2008,47(13):5971-5977
Controlled hydrolysis of strontium amide LSrN(SiMe 3) 2(thf) (L = CH(CMe2,6- i-Pr 2C 6H 3N) 2) ( 1) gave an unprecedented example of a hydrocarbon-soluble strontium hydroxide, [LSr(thf)(mu-OH) 2Sr(thf) 2L] ( 2). In compound 2, the tetrahydrofuran (THF) molecules can easily replaced by benzophenone and triphenylphosphine oxide to yield [LSr(mu-OH)(OCPh 2)] 2 ( 3) and [LSr(mu-OH)(OPPh 3)] 2 ( 4) compounds. Among the two strontium atoms of 2, one is coordinated to a single THF molecule, while the other is coordinated to two THF molecules. Interestingly, strontium hydroxide complex 2 behaves as an acid in its reaction with Zr(NMe 2) 4 and results in a heterobimetallic oxide, [LSr(mu-O)Zr(NMe 2) 3] 2 ( 5). Compound 5 is dimeric in the solid state and contains a Sr 2Zr 2O 2 core. 相似文献
5.
Chandrasekhar V Nagendran S Gopal K Steiner A Zacchini S 《Chemical communications (Cambridge, England)》2003,(7):862-863
A 1:2 reaction of Ph3SnOSnPh3 1 with RfCOOH 2 leads to the formation of [Ph2Sn(OH)OC(O)(Rf)]2 3, by means of a facile Sn-C bond cleavage process. 相似文献
6.
Chandrasekhar V Nagendran S Azhakar R Kumar MR Srinivasan A Ray K Chandrashekar TK Madhavaiah C Verma S Priyakumar UD Sastry GN 《Journal of the American Chemical Society》2005,127(8):2410-2411
Lipophilic hexaporphyrin free-base and copper-metalated assemblies supported on a Sn6O6 core have been synthesized and characterized. The nuclease activity of the copper derivative has been studied. 相似文献
7.
Ultrafiltration membranes are largely applied in the separation of heavy metal ion and macromolecular solutes from aqueous streams. Studies are presented on ultrafiltration blend membranes, based on cellulose acetate (CA) and polyetherimide (PEI) in various blend compositions. Polyethylene glycol (PEG 600) was employed as a non‐solvent additive in various concentrations to the casting solution to improve the ultrafiltration performance of the resulting membranes. The blend membranes prepared were characterized in terms of compaction time, pure water flux (PWF), water content, membrane resistance, and scanning electron microscopy (SEM). The molecular weight cut‐off (MWCO) obtained from the protein separation studies is also reported. Applications of these membranes for separating toxic metal ions from aqueous streams are discussed. Copyright © 2007 John Wiley & Sons, Ltd. 相似文献
8.
All the known polymorphs of Al(OH)3 comprise a stacking of charge neutral layers having the composition [Al2/3□1/3(OH)2] (□: cation vacancy) and designated by the symbol P. Employing a single Al(OH)3 layer (layer group p121/a1) as a structural synthon, the energy profile computed for the translations of P and $\bar{P}$ ($\bar{P}$ : mirror image of P) layers relative to each other within a bilayer model, not only show minima corresponding to the four known polymorphs of Al(OH)3 but also predict three new polymorphs with energy minima at the stacking vectors (7/10, 5/18, 1) (polymorph B1), (1/2, 0, 1) (polymorph B2) and (2/5, 1/9, 1) (polymorph B4). Of these B1 and B2 are 0.30 eV and 0.23 eV below the energy of bayerite (B3), but 0.30 eV and 0.37 eV above the global minimum which corresponds to gibbsite. B4 is only 0.08 eV above the energy of bayerite. This quantitative structural synthon approach offers B1, B2, and B4 as legitimate targets for future synthetic efforts. 相似文献
9.
S Sinhababu RK Siwatch G Mukherjee G Rajaraman S Nagendran 《Inorganic chemistry》2012,51(17):9240-9248
Fluorination of aminotroponiminate (ATI) ligand-stabilized germylene monochloride [(t-Bu)(2)ATI]GeCl (1) with CsF gave the aminotroponiminatogermylene monofluoride [(t-Bu)(2)ATI]GeF (2). Oxidative addition reaction of compound 2 with elemental sulfur and selenium led to isolation of the corresponding germathioacid fluoride [(t-Bu)(2)ATI]Ge(S)F (3) and germaselenoacid fluoride [(t-Bu)(2)ATI]Ge(Se)F (4), respectively. Similarly, reaction of aminotroponiminatogermylene monochloride [(i-Bu)(2)ATI]GeCl (9) with elemental sulfur and selenium gave the aminotroponiminatogermathioacid chloride [(i-Bu)(2)ATI]Ge(S)Cl (11) and aminotroponiminatogermaselenoacid chloride [(i-Bu)(2)ATI]Ge(Se)Cl (12), respectively. Compound 9 has been prepared through a multistep synthetic route starting from 2-(tosyloxy)tropone 5. All compounds (2-4 and 6-12) were characterized through the multinuclear NMR spectroscopy, and single-crystal X-ray diffraction studies were performed on compounds 2, 4, and 8-12. The germaselenoacid halide complexes 4 and 12 showed doublet (-142.37 ppm) and singlet (-213.13 ppm) resonances in their (77)Se NMR spectra, respectively. Germylene monohalide complexes 2 and 9 have a germanium center in distorted trigonal pyramidal geometry, whereas a distorted tetrahedral geometry is seen around the germanium center in germaacid halide complexes 4, 11, and 12. The length of the Ge═E bond in germathioacid chloride (11) and germaselenoacid halide (4 and 12) complexes is 2.065(1) and 2.194(av) ?, respectively. Theoretical studies (based on the DFT methods) on complexes 4, 11, and 12 reveal the nature of the Ge═E multiple bond in these germaacid halide complexes with computed Wiberg bond indices (WBI) being 1.480, 1.508, and 1.541, respectively. 相似文献
10.
Selvaraj Vetrivel Dipak Rana Meenakshi Sundaram Sri Abirami Saraswathi Kumar Divya Noel Jacob Kaleekkal Alagumalai Nagendran 《先进技术聚合物》2019,30(8):1943-1950
Hydrous manganese dioxide (HMO) nanoparticles incorporated cellulose acetate (CA) composite ultrafiltration (UF) membranes are prepared with the aim of improving the water permeation and BSA contaminant removal. The HMO nanoparticles are synthesized from manganese ion and characterized by FT‐IR, XRD, and FESEM. The effect of variation of HMO on CA membranes is probed using FT‐IR, EDAX, contact angle, SEM, and AFM analysis to demonstrate their chemical functionality, hydrophilicity, and morphology. CA/HMO membranes are showing the enhancement in pure water flux (PWF), water uptake, porosity, hydrophilicity, fouling resistance, BSA rejection, and flux recovery ratio (FRR). CA‐1 membrane displayed higher PWF (143.6 Lm2h?1), BSA rejection (95.9%), irreversible fouling (93.3%), and FRR (93.3%). Overall results confirmed that the CA/HMO nanocomposite UF membranes overcome the bottlenecks and shows potential for water treatment applications. 相似文献