Thangamuthu Rajendran - Academia.edu (original) (raw)
Papers by Thangamuthu Rajendran
Journal of Luminescence, 2019
Inorganica Chimica Acta, Aug 1, 2015
ABSTRACT
European Journal of Inorganic Chemistry, Feb 2, 2001
Journal of Photochemistry and Photobiology A-chemistry, Dec 1, 2014
Tetrahedron, May 1, 2005
Though electron transfer (ET) from the aromatic sulfide to the oxidant as the rate-determining st... more Though electron transfer (ET) from the aromatic sulfide to the oxidant as the rate-determining step has been proposed in many oxidation reactions, the formation of sulfide radical cation as the intermediate has only been confirmed in a few studies 5 , 7 , 32 , 33 and 34 since the ...
Inorganic Chemistry, Apr 19, 2000
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Journal of Innovative Research in Science, Engineering and Technology, 2013
Dalton Transactions, 2010
Inorganic Chemistry, Jul 18, 2003
Self-assembly of rhenium-based nanoscale rectangular prismatic boxes has been achieved in quantit... more Self-assembly of rhenium-based nanoscale rectangular prismatic boxes has been achieved in quantitative conversion. The facrhenium corner provided three mutually perpendicular coordination sites and served as a good candidate for the construction of 3-D boxes. These are the first Re-based, neutral, luminescent prisms of M 8 L 2 L′ 8 type that has been characterized crystallographically. Their luminescent properties and molecular recognition capabilities make these molecular prisms interesting supramolecules.
Electrocatalysis, May 8, 2021
The present work reports the selective oxidation of L-cysteine (L-Cys), L-methionine (L-Met), and... more The present work reports the selective oxidation of L-cysteine (L-Cys), L-methionine (L-Met), and methionine–glycine (Met-Gly) in phosphate buffer (PB) (pH = 7.2) using [oxoiron(IV)–salen] ion immobilized glassy carbon electrode (FeIV/Nf/GC electrode). The cyclic voltammogram (CV) of the modified GC electrode shows a clear oxidation peak at 1.18 (± 0.02) V, assigned to FeIII/FeIV redox couple. The differential pulse voltammograms (DPV) show a well-defined oxidation peak at 1.32 (± 0.02) V for oxidation of L-Cys, 1.26 (± 0.02) V for L-Met and 1.51 (± 0.02) V for Met-Gly, respectively. Cyclic voltammetric (CV) response of oxidation peak current increases linearly with increase the concentration of L-Cys, L-Met, and Met-Gly in the concentration ranges about 0.4–20 μM with the correlation coefficient value (R2) of 0.99, and the detection limits are found to be 0.3 μM (S/N = 3), 0.2 μM (S/N = 3), and 0.3 μM (S/N = 3), respectively. The present modified electrode exhibits good catalytic activity towards the oxidation of L-Cys, L-Met, and Met-Gly. The electrochemical oxidation of L-Cys, L-Met, and Met-Gly follows the electron transfer mechanism and provides L-cysteine (–S–S–, a disulfide), methionine sulfoxide (MetSO), and sulfone (MetSO2) as the major products. The present modified electrode is successfully applied to the medicinally important real samples and gets good recovery results. The present work reports the stable and selective determination of a). L-Cysteine (L-Cys), b).L-Methionine (L-Met) and Methionine-Glycine (Met-Gly) in phosphate buffer (pH = 7.2) using [oxoiron(IV)-salen] ion immobilized glassy carbon electrode (FeIV/Nf/GC electrode).
Journal of Physical Chemistry A, Jun 16, 2014
In order to develop a new photocatalytic system, we designed a new redox-active module (5) to hol... more In order to develop a new photocatalytic system, we designed a new redox-active module (5) to hold both a photosensitizer part, [Ru(II)(terpy)(bpy)X](n+) (where terpy = 2,2':6',2''-terpyridine and bpy = 2,2'-bipyridine), and a popular Jacobsen catalytic part, salen-Mn(III), covalently linked through a pyridine-based electron-relay moiety. On the basis of nanosecond laser flash photolysis studies, an intramolecular electron transfer mechanism from salen-Mn(III) to photooxidized Ru(III) chromophore yielding the catalytically active high-valent salen-Mn(IV) species was proposed. To examine the reactivity of such photogenerated salen-Mn(IV), we employed organic sulfide as substrate. Detection of the formation of a Mn(III)-phenoxyl radical and a sulfur radical cation during the course of reaction using time-resolved transient absorption spectroscopy confirms the electron transfer nature of the reaction. This is the first report for the electron transfer reaction of organic sulfide with the photochemically generated salen-Mn(IV) catalytic center.
Journal of Physical Chemistry A, Oct 5, 2007
Alkoxy-bridged rhenium(I) rectangles [{(CO) 3 Re(µ-OR) 2 Re(CO) 3 } 2 (µ-bpy) 2 ] (1, R) C 4 H 9 ... more Alkoxy-bridged rhenium(I) rectangles [{(CO) 3 Re(µ-OR) 2 Re(CO) 3 } 2 (µ-bpy) 2 ] (1, R) C 4 H 9 ; 2, R) C 8 H 17 ; 3, R) C 12 H 25 ; bpy) 4,4′-bipyridine) comprising long alkyl chains form optically transparent aggregates and exhibit luminescence enhancement in the presence of water. The aggregation of Re(I)-rectangle was followed using a light-scattering technique. Presumably, the enhanced luminescence efficiency resulted from restriction of torsional molecular motion in the aggregates. In addition, the rate of bimolecular quenching of Re(I)aggregates in the triplet excited state by various electron donors (amines) and acceptors (quinones) was efficient. These results indicate that the excited state of aggregated Re(I) surfactants with an electron acceptor and donor facilitate the electron-transfer quenching process after they became preassociated inside the Re(I)aggregated species. These synthesized compounds may be useful fluorescent materials in optoelectronic applications.
Physical Chemistry Chemical Physics, 2001
The present work involves an attempt to prepare two Ruthenium(II) complexes [Ru(bpy)3]2+ (I) and ... more The present work involves an attempt to prepare two Ruthenium(II) complexes [Ru(bpy)3]2+ (I) and [Ru(phen)3]2+ (II) by simple and effective one-pot synthesis in a greener way and we have succeeded in achieving the target compounds in very good yields. Furthermore, we have studied extensively the photochemical reduction of complex I and II , *[Ru(NN)3]2+ in their excited states with various aromatic amines in the absence and presence of oxygen molecules by the luminescence quenching technique. The quenching rate constants, kq for each photoredox reactions have been determined using Stern-Volmer analysis. The results exhibit an interesting trend which depends on the nature of the quencher. In particular, the result proves the efficient interacting mechanism of oxygen with the excited state of *[Ru(NN) 3 ] 2+ .
Journal of Physical Chemistry A, Oct 1, 1997
Photoinduced electron transfer (ET) is one of the very active areas of research in chemistry in t... more Photoinduced electron transfer (ET) is one of the very active areas of research in chemistry in this decade. 1-4 The rate of electron transfer from a donor molecule to an acceptor in a solvent is controlled by several factors and the most important of them are the free energy change ...
Arabian journal for science and engineering, Feb 21, 2015
Herein, we report the solvothermal method for the synthesis of iron(III)-salen complexes (salen =... more Herein, we report the solvothermal method for the synthesis of iron(III)-salen complexes (salen = N,N-bis (salicylidene)ethylenediaminato) from salicylaldehyde, 2,2bis ethylenediamine and ferric chloride in a single step. The solvothermal method involves the synthesis of complexes with good quality having excellent control on the composition. An insight into the spectral, computational, electrochemical and antibacterial studies highlights the structural, Electronic supplementary material The online version of this article (
The quenching rate constants (k q) of quenching of excited *RuL5+ complexes (L is 4,4'-dialkyl-2,... more The quenching rate constants (k q) of quenching of excited *RuL5+ complexes (L is 4,4'-dialkyl-2,2'-bipyridine) by substituted styrylpyridines are neither influenced by increase in size of the alkyl group of the sensitizer nor by the substituent in the quencher and energy transfer seems to be predominant. However, in the quenching of *RuL5+ by 4'-nitro-4-styrylpyridine and 4-methyl-4-styrylpyridinium iodide both electron transfer and energy transfer seem to occur.
Russian Journal of Physical Chemistry A, 2021
The emission spectra and lifetime of cationic complexes [Ru(NN)3]2+ are highly influenced by the ... more The emission spectra and lifetime of cationic complexes [Ru(NN)3]2+ are highly influenced by the presence of anionic surfactant sodium dodecyl sulfate (SDS). The rate of photoreduction of [Ru(NN)3]2+ with ArO– is facilitated by the decrease in the polarity of the solvent. On the other hand, addition of SDS entails initial decrease in the quenching constant, kq. The change of kq value with the increase in [SDS] depends on the structure of phenolate ion. With phenolate ions containing alkyl groups, micellar catalysis is observed at high [SDS]. These results on micellar effect are accounted for in terms of pseudo phase ion exchange model.
Journal of Luminescence, 2019
Inorganica Chimica Acta, Aug 1, 2015
ABSTRACT
European Journal of Inorganic Chemistry, Feb 2, 2001
Journal of Photochemistry and Photobiology A-chemistry, Dec 1, 2014
Tetrahedron, May 1, 2005
Though electron transfer (ET) from the aromatic sulfide to the oxidant as the rate-determining st... more Though electron transfer (ET) from the aromatic sulfide to the oxidant as the rate-determining step has been proposed in many oxidation reactions, the formation of sulfide radical cation as the intermediate has only been confirmed in a few studies 5 , 7 , 32 , 33 and 34 since the ...
Inorganic Chemistry, Apr 19, 2000
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
An entry from the Cambridge Structural Database, the world's repository for small molecule cr... more An entry from the Cambridge Structural Database, the world's repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.
International Journal of Innovative Research in Science, Engineering and Technology, 2013
Dalton Transactions, 2010
Inorganic Chemistry, Jul 18, 2003
Self-assembly of rhenium-based nanoscale rectangular prismatic boxes has been achieved in quantit... more Self-assembly of rhenium-based nanoscale rectangular prismatic boxes has been achieved in quantitative conversion. The facrhenium corner provided three mutually perpendicular coordination sites and served as a good candidate for the construction of 3-D boxes. These are the first Re-based, neutral, luminescent prisms of M 8 L 2 L′ 8 type that has been characterized crystallographically. Their luminescent properties and molecular recognition capabilities make these molecular prisms interesting supramolecules.
Electrocatalysis, May 8, 2021
The present work reports the selective oxidation of L-cysteine (L-Cys), L-methionine (L-Met), and... more The present work reports the selective oxidation of L-cysteine (L-Cys), L-methionine (L-Met), and methionine–glycine (Met-Gly) in phosphate buffer (PB) (pH = 7.2) using [oxoiron(IV)–salen] ion immobilized glassy carbon electrode (FeIV/Nf/GC electrode). The cyclic voltammogram (CV) of the modified GC electrode shows a clear oxidation peak at 1.18 (± 0.02) V, assigned to FeIII/FeIV redox couple. The differential pulse voltammograms (DPV) show a well-defined oxidation peak at 1.32 (± 0.02) V for oxidation of L-Cys, 1.26 (± 0.02) V for L-Met and 1.51 (± 0.02) V for Met-Gly, respectively. Cyclic voltammetric (CV) response of oxidation peak current increases linearly with increase the concentration of L-Cys, L-Met, and Met-Gly in the concentration ranges about 0.4–20 μM with the correlation coefficient value (R2) of 0.99, and the detection limits are found to be 0.3 μM (S/N = 3), 0.2 μM (S/N = 3), and 0.3 μM (S/N = 3), respectively. The present modified electrode exhibits good catalytic activity towards the oxidation of L-Cys, L-Met, and Met-Gly. The electrochemical oxidation of L-Cys, L-Met, and Met-Gly follows the electron transfer mechanism and provides L-cysteine (–S–S–, a disulfide), methionine sulfoxide (MetSO), and sulfone (MetSO2) as the major products. The present modified electrode is successfully applied to the medicinally important real samples and gets good recovery results. The present work reports the stable and selective determination of a). L-Cysteine (L-Cys), b).L-Methionine (L-Met) and Methionine-Glycine (Met-Gly) in phosphate buffer (pH = 7.2) using [oxoiron(IV)-salen] ion immobilized glassy carbon electrode (FeIV/Nf/GC electrode).
Journal of Physical Chemistry A, Jun 16, 2014
In order to develop a new photocatalytic system, we designed a new redox-active module (5) to hol... more In order to develop a new photocatalytic system, we designed a new redox-active module (5) to hold both a photosensitizer part, [Ru(II)(terpy)(bpy)X](n+) (where terpy = 2,2':6',2''-terpyridine and bpy = 2,2'-bipyridine), and a popular Jacobsen catalytic part, salen-Mn(III), covalently linked through a pyridine-based electron-relay moiety. On the basis of nanosecond laser flash photolysis studies, an intramolecular electron transfer mechanism from salen-Mn(III) to photooxidized Ru(III) chromophore yielding the catalytically active high-valent salen-Mn(IV) species was proposed. To examine the reactivity of such photogenerated salen-Mn(IV), we employed organic sulfide as substrate. Detection of the formation of a Mn(III)-phenoxyl radical and a sulfur radical cation during the course of reaction using time-resolved transient absorption spectroscopy confirms the electron transfer nature of the reaction. This is the first report for the electron transfer reaction of organic sulfide with the photochemically generated salen-Mn(IV) catalytic center.
Journal of Physical Chemistry A, Oct 5, 2007
Alkoxy-bridged rhenium(I) rectangles [{(CO) 3 Re(µ-OR) 2 Re(CO) 3 } 2 (µ-bpy) 2 ] (1, R) C 4 H 9 ... more Alkoxy-bridged rhenium(I) rectangles [{(CO) 3 Re(µ-OR) 2 Re(CO) 3 } 2 (µ-bpy) 2 ] (1, R) C 4 H 9 ; 2, R) C 8 H 17 ; 3, R) C 12 H 25 ; bpy) 4,4′-bipyridine) comprising long alkyl chains form optically transparent aggregates and exhibit luminescence enhancement in the presence of water. The aggregation of Re(I)-rectangle was followed using a light-scattering technique. Presumably, the enhanced luminescence efficiency resulted from restriction of torsional molecular motion in the aggregates. In addition, the rate of bimolecular quenching of Re(I)aggregates in the triplet excited state by various electron donors (amines) and acceptors (quinones) was efficient. These results indicate that the excited state of aggregated Re(I) surfactants with an electron acceptor and donor facilitate the electron-transfer quenching process after they became preassociated inside the Re(I)aggregated species. These synthesized compounds may be useful fluorescent materials in optoelectronic applications.
Physical Chemistry Chemical Physics, 2001
The present work involves an attempt to prepare two Ruthenium(II) complexes [Ru(bpy)3]2+ (I) and ... more The present work involves an attempt to prepare two Ruthenium(II) complexes [Ru(bpy)3]2+ (I) and [Ru(phen)3]2+ (II) by simple and effective one-pot synthesis in a greener way and we have succeeded in achieving the target compounds in very good yields. Furthermore, we have studied extensively the photochemical reduction of complex I and II , *[Ru(NN)3]2+ in their excited states with various aromatic amines in the absence and presence of oxygen molecules by the luminescence quenching technique. The quenching rate constants, kq for each photoredox reactions have been determined using Stern-Volmer analysis. The results exhibit an interesting trend which depends on the nature of the quencher. In particular, the result proves the efficient interacting mechanism of oxygen with the excited state of *[Ru(NN) 3 ] 2+ .
Journal of Physical Chemistry A, Oct 1, 1997
Photoinduced electron transfer (ET) is one of the very active areas of research in chemistry in t... more Photoinduced electron transfer (ET) is one of the very active areas of research in chemistry in this decade. 1-4 The rate of electron transfer from a donor molecule to an acceptor in a solvent is controlled by several factors and the most important of them are the free energy change ...
Arabian journal for science and engineering, Feb 21, 2015
Herein, we report the solvothermal method for the synthesis of iron(III)-salen complexes (salen =... more Herein, we report the solvothermal method for the synthesis of iron(III)-salen complexes (salen = N,N-bis (salicylidene)ethylenediaminato) from salicylaldehyde, 2,2bis ethylenediamine and ferric chloride in a single step. The solvothermal method involves the synthesis of complexes with good quality having excellent control on the composition. An insight into the spectral, computational, electrochemical and antibacterial studies highlights the structural, Electronic supplementary material The online version of this article (
The quenching rate constants (k q) of quenching of excited *RuL5+ complexes (L is 4,4'-dialkyl-2,... more The quenching rate constants (k q) of quenching of excited *RuL5+ complexes (L is 4,4'-dialkyl-2,2'-bipyridine) by substituted styrylpyridines are neither influenced by increase in size of the alkyl group of the sensitizer nor by the substituent in the quencher and energy transfer seems to be predominant. However, in the quenching of *RuL5+ by 4'-nitro-4-styrylpyridine and 4-methyl-4-styrylpyridinium iodide both electron transfer and energy transfer seem to occur.
Russian Journal of Physical Chemistry A, 2021
The emission spectra and lifetime of cationic complexes [Ru(NN)3]2+ are highly influenced by the ... more The emission spectra and lifetime of cationic complexes [Ru(NN)3]2+ are highly influenced by the presence of anionic surfactant sodium dodecyl sulfate (SDS). The rate of photoreduction of [Ru(NN)3]2+ with ArO– is facilitated by the decrease in the polarity of the solvent. On the other hand, addition of SDS entails initial decrease in the quenching constant, kq. The change of kq value with the increase in [SDS] depends on the structure of phenolate ion. With phenolate ions containing alkyl groups, micellar catalysis is observed at high [SDS]. These results on micellar effect are accounted for in terms of pseudo phase ion exchange model.