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1.
Sekarpandi Sakthivel Suribabu Jammi Tharmalingam Punniyamurthy 《Tetrahedron: Asymmetry》2012,23(2):101-107
Stereoregular non-linear chiral main chain polymers 1a–b bonded alternatively with (R,R)-salen and 1,4-diethynyl-2,5-dioctyloxybenzene moieties have been synthesized using palladium catalyzed C–C cross-coupling and Schiff base formation reactions as the key steps. These polymers are soluble in common organic solvents, and act as an effective chemosensor for the detection of Zn2+ with respect to other metal ions with enhanced fluorescence. The CD spectra observed for the polymers 1a–b could be attributed to the helical secondary structure with a low degree of inter-strand interactions. This reduced inter-strand interaction has been ascertained from the titration of pyridine to the Zn(II)-polymer 1b complex, which results in minor changes in the fluorescence emission. 相似文献
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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
3.
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
4.
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
5.
A copper(II)-catalyzed conversion of bisaryloxime ethers to 2-arylbenzoxazoles has been developed. The reaction involves a cascade C-H functionalization and C-N/C-O bond formation under oxygen atmosphere. 相似文献
6.
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
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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
9.
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
10.
Govindarasu Murugavel Pradeep Sadhu Tharmalingam Punniyamurthy 《Chemical record (New York, N.Y.)》2016,16(4):1906-1917
Self‐assembled copper(II) complexes are described as effective catalysts for nitroaldol (Henry) reactions on water. The protocol involves a heterogeneous process and the catalysts can be recovered and recycled without loss of activity. Further, C2‐symmetric N,N′‐substituted chiral copper(II) salan complexes are found to be more effective catalysts than chiral copper(II) salen complexes for reactions in homogeneous catalysis, with high enantioselectivities. The reactions involve bifunctional catalysis, bearing the properties of a Brønsted base, as well as a Lewis acid, to effect the reaction in the absence of external additives. 相似文献