Mangalampalli Ravikanth

Indian Institute of Technology Bombay, Mumbai, Maharashtra, India

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Publications (178)575.57 Total impact

  • Emandi Ganapathi · Tamal Chatterjee · Mangalampalli Ravikanth ·
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    ABSTRACT: A series of fluorescent BIII complexes of meso-triaryl-substituted 25-oxasmaragdyrins containing axial silyloxy groups were prepared in 80–85 % yields by treating B(OH)2 complexes of meso-triaryl 25-oxasmaragdyrins with different alkyl/aryl chlorosilanes in toluene in the presence of base at reflux temperature followed by simple column chromatographic purification. The eight axially silyloxy-substituted BIII complexes of smaragdyrins were freely soluble in common organic solvents and were characterized by HRMS, 1D and 2D NMR, absorption, fluorescence and electrochemical studies, as well as by X-ray crystallography in the case of one of the complexes. The crystal structure revealed that the smaragdyrin macrocycle is almost planar and that the –OSiMe3 groups on BIII are oriented in the up and down directions relative to the macrocycle. The absorption studies indicated that the axially silyloxy-substituted BIII smaragdyrins are strongly absorbing in the 710–440 nm region with absorption coefficients higher than those of B(OH)2-smaragdyrin complexes. The silylation of –OH groups at the BIII centrein the BIII smaragdyrin complex results in five- to sixfold enhancements in the fluorescence quantum yields and in longer singlet state lifetimes. Thus, the axial silyloxy BIII complexes are strongly fluorescent with quantum yields in the 0.65–0.78 range and singlet state lifetimes in the 4.3–4.9 ns range. The complexes are highly stable under redox conditions and each exhibit two reversible oxidations and one reversible reduction.
    Berichte der deutschen chemischen Gesellschaft 09/2015; 2015(29). DOI:10.1002/ejic.201500718 · 2.94 Impact Factor
  • Booruga Umasekhar · Emandi Ganapathi · Tamal Chatterjee · Mangalampalli Ravikanth ·
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    ABSTRACT: meso-Pyrrolyl boron dipyrromethene (BODIPY) was prepared under simple reaction conditions by using commercially available chemicals. Prior to this work, the BODIPY compound was prepared in multiple steps by using precursors which were not readily available. The X-ray structure of BODIPY revealed that the meso-pyrrole ring is tilted towards the BF2-dipyrrin moiety with a dihedral angle of 33.94°. The reactivity of the meso-pyrrole ring of BODIPY was tested by subjecting it to bromination and formylation reactions, which afforded (α-bromopyrrolyl) BODIPY and (α-formylpyrrolyl) BODIPY in decent yields. The (α-formylpyrrolyl) BODIPY was used to prepare the pyrrole bridged BODIPY dyad. The pyrrole bridged BODIPY dyad exhibited a 15-20 nm bathochromic shift in the absorption band and was weakly fluorescent compared to meso-pyrrolyl BODIPY. Furthermore, our studies show that the meso-pyrrolyl BODIPY can be used as a specific sensor for F(-) ions because of the presence of meso-pyrrole NH which is involved in interactions with F(-) ions. To prove that meso-pyrrole NH is involved in sensing F(-) ions, we also prepared meso-(N-methylpyrrolyl)-BODIPY and characterized it by various spectroscopic techniques and crystallography. Our studies reveal that meso-(N-methylpyrrolyl)-BODIPY does not sense F(-) ions, supporting the involvement of meso-pyrrole NH in sensing F(-) ions.
    Dalton Transactions 09/2015; 44(37). DOI:10.1039/c5dt02634b · 4.20 Impact Factor
  • Source
    Sunit Kumar · Tamanna K. Khan · Mangalampalli Ravikanth ·
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    ABSTRACT: Sterically crowded 1,2,3,5,6,7-hexaarylated azaBODIPYs were synthesized in 25–35% yields by coupling 1,3,5,7-tetraaryl azaBODIPYs with six different aryl boronic acids under Pd(0) coupling conditions. The moderate reaction yields were attributed to steric congestion caused by two additional aryl groups introduced at the tetraaryl azaBODIPY core. The compounds were characterized by HRMS, 1D and 2D NMR spectroscopic techniques. The 1H, 19F and 11B NMR studies of hexaarylated azaBODIPYs showed slight upfield shifts compared to tetraaryl azaBODIPY indicating the slight alteration of electronic properties of azaBODIPY core upon introduction of two additional aryl groups on tetrararyl azaBODIPY. The absorption and fluorescence bands of hexaarylated azaBODIPYs experienced 7–10 nm hypsochromic shifts compared to tetraaryl azaBODIPY. The hexaarylated azaBODIPYs are weakly fluorescent with significant reduction in quantum yields and singlet state lifetimes compared to tetraarylated azaBODIPY.
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    ABSTRACT: Unprecedented examples of smaragdyrin macrocycles containing seven membered heterocyclic rings were synthesized under simple reaction conditions in high yields. The heterocycle formed inside smaragdyrin macrocycle is rare example of heterocycle containing five different atoms, such as B, C, N, O, and P atoms. The mixed BIII and PV complexes of smaragdyrin macrocycles showed new structural, spectral, and electrochemical properties. Heterocycle inside macrocycle! A stable, unprecedented heterocycle made up of five different atoms, such as C, B, N, O, and P, inside a macrocycle has been synthesized. The heterocycle formed inside the smaragdyrin macrocycle represents the rare example of a heterocycle containing five different atoms (see figure).
    Chemistry - A European Journal 07/2015; 21(32):1-6. DOI:10.1002/chem.201501889 · 5.73 Impact Factor
  • Source
    Sunit Kumar · Habtom B Gobeze · Tamal Chatterjee · Francis D'Souza · Mangalampalli Ravikanth ·
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    ABSTRACT: Directly connected, strongly interacting sensitizer donor-acceptor dyads mimic light induced photochemical events of photosynthesis. Here, we have devised a dyad composed of BF2-chelated dipyrromethene (BODIPY) directly linked to BF2-chelated tetraarylazadipyrromethene (azaBODIPY) through the -pyrrole position of azaBODIPY. Structural integrity of the dyad was arrived from 2D NMR (1H-1H COSY and NOESY) spectral studies while single crystal X-ray structure of the dyad provided the relative orientation of the two macrocycles to be ~62o. Due to direct linking of the two entities, ultrafast energy transfer from the 1BODIPY* to azaBODIPY was witnessed. A good agreement between the theoretically estimated Förster energy transfer rate and experimentally determined rate was observed, and this rate was found to be higher than that reported for BODIPY-azaBODIPY analogs connected with spacer units. In agreement with the free-energy calculations, the product of energy transfer, 1azaBODIPY* revealed additional photochemical events such as electron transfer leading to the creation of BODIPY•+-azaBODIPY•- radical ion-pair, more so in polar benzonitrile than in nonpolar toluene, as evidenced by femtosecond transient spectroscopic studies. Additionally, the spectral, electrochemical and photochemical studies of the precursor compound, azaBODIPY-dipyrromethane also revealed occurrence of excited state events. In this case, electron transfer from the 1azaBODIPY* to dipyrromethane (DPM) to yield DPM•+-azaBODIPY•- charge separated state. The study described here the stresses the role of close association of the donor and acceptor entities to promote ultrafast photochemical events, applicable of building fast responding optoelectronic and energy harvesting devices.
    The Journal of Physical Chemistry A 07/2015; 119(30). DOI:10.1021/acs.jpca.5b06328 · 2.69 Impact Factor
  • Venugopal Bandi · Habtom B. Gobeze · Vellanki Lakshmi · Mangalampalli Ravikanth · Francis D’Souza ·
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    ABSTRACT: A donor-acceptor dyad composed of BF2-chelated dipyrromethene (BDP or BODIPY) and fullerene connected with a pyrrole ring spacer, 1, has been newly synthesized and characterized. Because of α-carbon substitution and extended conjugation offered by the pyrrole ring, the optical absorbance and emission spectra of BDP macrocycle were found to be red-shifted significantly. Electrochemical studies provided information on the redox potentials while computational studies performed at the B3LYP/6-31G∗ level yielded an optimized geometry of the dyad that was close to that reported earlier for a BDP-C60 dyad covalently connected through the central boron atom, 2. The HOMO of the dyad was found to be on the BDP macrocycle, extended over the pyrrole bridging group, a property that is expected to facilitate electronic communication between the BDP and fullerene entities. The established energy level diagram using spectral, redox, and optimized structural results predicted possibility of photoinduced electron transfer in both benzonitrile and toluene, representing polar and nonpolar solvents. However, such energy diagram suggested different routes for the charge recombination processes, that is, direct relaxation of the radical ion-pair in polar solvent while populating the triplet level of the sensitizer (3BDP∗ or 3C60∗) in nonpolar solvent. Proof for charge separation and solvent dependent charge recombination processes were established from studies involving femto- and nanosecond pump-probe spectroscopy. The measured rate of charge separation, kCS, for 1 was higher in both solvents compared to the earlier reported values for 2 due to electronically well-communicating pyrrole spacer. The charge recombination in toluene populated 3BDP∗ as an intermediate step while in benzonitrile it yielded directly ground state of the dyad. The present findings reveal the significance of pyrrole spacer between the donor and acceptor to facilitate charge separation and solvent polarity dependent charge recombination processes.
    The Journal of Physical Chemistry C 04/2015; 119(15):8095-8102. DOI:10.1021/acs.jpcc.5b02712 · 4.77 Impact Factor
  • Hemanta Kalita · Mangalampalli Ravikanth ·
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    ABSTRACT: Novel boron-dipyrromethene (BODIPY)-bridged 22-oxacorrole dyads, using meso-pyrrolyl 22-oxacorrole as a key synthon, have been synthesized. The reactivity of the meso-pyrrolyl group of 22-oxacorrole was exploited to synthesize the first examples of BODIPY-bridged 22-oxacorrole dyads in ≈40 % yield. The dyads are stable and exhibited interesting spectral and electrochemical properties. BODIPY selecta! A class of novel BODIPY-bridged 22-oxacorrole dyads have been synthesized by exploiting the reactivity of the meso-pyrrole group of meso-pyrrolyl meso-free 22-oxacorrole (see scheme; ET=energy transfer).
    Chemistry - A European Journal 04/2015; 21(20). DOI:10.1002/chem.201500702 · 5.73 Impact Factor
  • Mangalampalli Ravikanth · Emandi Ganapathi · Tamal Chatterjee · Way-Zen Lee ·
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    ABSTRACT: Our successful synthesis of first examples of nonaromatic 24 core-modified pentaphyrins containing six meso carbons is reported.The core-modified pentaphyrins containing six meso carbons were prepared by [3+2] condensation of butane-2,3-diyl-bisthiophene-2,5-diyl-bis(p-methoxyphenylmethanol)with different meso-aryl tripyrromethanes under mild acid-catalyzed conditions.By this methodology, we obtained two stable core-modified pentaphyrins containing six meso carbons in decent yields.The core-modified pentaphyrins were characterized by HR-MS, 1D, 2D NMR, absorption and electrochemical techniques and also by X-ray crystallography for one of the pentaphyrin macrocycle.The crystal structure revealed that the macrocycles is almost planar and one of the thiophene rings which is positioned opposite to the ethene bridged meso-carbons is inverted.Our studies revealed that the macrocycles in their protonated form have specific sensing ability for CH3COO- ion.
    Asian Journal of Organic Chemistry 04/2015; 4(7). DOI:10.1002/ajoc.201500072 · 3.32 Impact Factor
  • Tejinder Kaur · Tamanna K. Khan · Mangalampalli Ravikanth ·
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    ABSTRACT: Cyclotriphosphazene and cyclotetraphosphazene appended with six and eight sapphyrin units, respectively, were prepared by treating N3P3Cl6 and N4P4Cl8 with the appropriate equivalents of 5,10,15-tri(p-tolyl)-20-(4-hydroxyphenyl)-25,27,29-trithiasapphyrin in tetrahydrofuran (THF) in the presence of Cs2CO3 at temperatures of 0 to 60 °C for 8–12 h. The two multi-expanded porphyrin assemblies were soluble in common organic solvents, and their identities were confirmed by their corresponding molecular ion peak in the MALDI-TOF mass spectra. 1D and 2D NMR spectroscopic techniques were used to deduce the molecular structures of the mult-expanded porphyrin assemblies. Absorption spectral studies showed that the band positions of the multisapphyrin assemblies were similar to that of the monomeric sapphyrin, but the extinction coefficients were three- to fourfold higher than that of the monomeric sapphyrin. The multisapphyrin assemblies are not very stable under redox conditions.
    European Journal of Organic Chemistry 03/2015; 2015(14). DOI:10.1002/ejoc.201500131 · 3.07 Impact Factor
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    ABSTRACT: Miniaturization of integrated circuits is happening at a rapid pace since the last two decades. Physical limits are beginning to saturate the growth of Si-CMOS technology and have prompted technologists to look for alternative approaches for miniaturization. Molecular Electronics is proving to be a viable option to fabricating high-density circuits, leveraging properties of organic molecules. Carbon nanotubes, polyphenylenes, porphyrins and DNA strands are some of the molecules that are being actively researched upon. In this article the current status of research in the area of molecular electronics is reviewed, and the roadblocks identified using an extensive database of research in this area. The current research efforts in the area of molecular electronics at IIT Bombay are also briefly discussed.
    IETE Technical Review 03/2015; 19(5):307-315. DOI:10.1080/02564602.2002.11417045 · 0.89 Impact Factor
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    Tamal Chatterjee · Sivaiah Areti · Mangalampalli Ravikanth ·
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    ABSTRACT: The first stable calixazasmaragdyrins containing two meso-sp(2) and one meso-sp(3) carbon atoms were synthesized by [3 + 2] condensation of 2,2'-(1-methylethylidene)bis(pyrrole) and 5,10-diaryltripyrromethane under trifluoroacetic acid catalyzed conditions. The macrocycles were confirmed by high-resolution mass spectrometry, and the molecular structures were deduced by detailed 1D and 2D NMR spectroscopy. The single-crystal structural analysis showed the highly strained and distorted nature of a calixazasmaragdyrin macrocycle. The presence of the one meso-sp(3) carbon center induces sufficient flexibility into the macrocycle, which, in turn, helps with the stability of the calixazasmaragdyrin macrocycle. The calixazasmargdyrins showed one broad absorption band at ∼425 nm and an ill-defined band at ∼685 nm. The electrochemical studies revealed that the calixazasmaragdyrins are not stable under redox conditions. Because the calixazasmargdyrin macrocycle possesses five pyrrole rings with three ionizable inner NH protons, we investigated anion and cation sensing properties of calixazasmargdyrins. Our studies revealed that the calixazasmaragdyrins do not show any sensing behavior toward anions but exhibited specific sensing behavior toward Hg(2+) ions as verified by spectral and electrochemical studies.
    Inorganic Chemistry 03/2015; 54(6). DOI:10.1021/ic503028k · 4.76 Impact Factor
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    A. Dvivedi · P. Rajakannu · M. Ravikanth ·
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    ABSTRACT: The meso-salicylaldehyde substituted BODIPY was synthesized over sequence of steps and characterized by X-ray crystallography, mass, NMR, absorption, fluorescence and electrochemical techniques. The crystal structure showed the presence of strong intramolecular hydrogen bonding between hydroxyl and formyl group which induces rigidity in the BODIPY core and makes the BODIPY relatively more fluorescent compared to meso-phenyl BODIPY. Our studies showed that the meso-salicyaldehyde BODIPY can be used as specific chemidosimetric sensor for CN- ion. The presence of hydroxyl group adjacent to formyl group helps in activating the formyl group for nucleophilic attack. Upon addition of CN- ion to meso-salicylaldehyde BODIPY, the CN- ion attacks the formyl group and converts to cyanohydrin group. This irreversible reaction was monitored by following the changes in absorption, fluorescence and electrochemical properties and the results support that meso-salicylaldehyde substituted BODIPY can be used as specific chemodosimetric sensor for CN- ion. To substantiate the role of hydroxyl group, we also prepared meso(m-formylphenyl) BODIPY which contains only formyl group on meso-phenyl and our studies indicated that meso(m-formylphenyl) BODIPY cannot be used as chemodosimetric sensor for CN- ion, as verified by absorption and emission studies.
    Dalton Transactions 01/2015; · 4.20 Impact Factor
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    Emandi Ganapathi · Tamal Chatterjee · Mangalampalli Ravikanth ·
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    ABSTRACT: Expanded dithiacalixphyrins with the N2S2 core containing two sp(3) and three sp(2)meso-carbons have been prepared by condensation of one equivalent of butene-2,3-diyl-bisthiophene-2,5-diyl-bis(p-methoxyphenylmethanol) with one equivalent of 5,5'-dialkyldipyrromethane under mild acid catalyzed conditions in decent yields. The expanded dithiacalixphyrins were characterized by HR-MS, 1D and 2D NMR techniques and the structure of one of the expanded dithiacalixphyrin macrocycles was solved by X-ray crystallography. The crystal structure analysis indicated that the macrocycle is highly distorted and attains a boat shaped structure. The expanded thiacalixphyrins showed a specific sensing ability for F(-) ions over other anions as judged from absorption, NMR and mass spectral studies.
    Dalton Transactions 12/2014; 44(6). DOI:10.1039/c4dt03215b · 4.20 Impact Factor
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    Sunit Kumar · Mangalampalli Ravikanth ·
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    ABSTRACT: A series of functionalized meso-boron dipyrromethenyl porphyrin building blocks were synthesized by condensing one equivalent of readily available 2-formyl boron dipyrromethene (2-formyl BODIPY) with two equivalents of meso-anisyl dipyrromethane and one equivalent of functionalized aldehyde under mild acid catalyzed conditions followed by column chromatographic purification and afforded in 5–7% yields. The meso-BODIPYnyl porphyrins are freely soluble in common organic solvents and characterized by mass, spectral and electrochemical techniques. The presence of a BODIPY unit directly at the meso-position alters the π-delocalization of the porphyrin macrocycle. The compounds are weakly fluorescent because of effective charge transfer between the porphyrin and BODIPY units leading to the formation of a low lying charge transfer state. The meso-BODIPYnyl porphyrin–BF2–smaragdyrin conjugate was synthesized by coupling a meso-BODIPYnyl porphyrin building block containing a meso-iodophenyl group with ethynyl BF2–smaragdyrin under Pd(0) coupling conditions. The spectral and electrochemical studies indicated that the photo-induced electron transfer is the predominant process in the meso-BODIPYnyl porphyrin–BF2–smaragdyrin conjugate.
    RSC Advances 11/2014; 4(109). DOI:10.1039/C4RA10807H · 3.84 Impact Factor
  • Tejinder Kaur · Malakalapalli Rajeswararao · Mangalampalli Ravikanth ·
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    ABSTRACT: We report the synthesis of first examples of hexaporphyrin and dodecaporphyrin assemblies on cyclotriphosphazene scaffold by adopting two different approaches based on Ru-pyridyl "N" coordination in decent yields. The multiporphyrin assemblies were confirmed by (31)P, (13)C, (1)H, (1)H-(1)H COSY, and NOESY NMR spectroscopic studies. The absorption studies showed 2-fold intensity enhancement with negligible changes in peak maxima compared to porphyrin monomers. The redox potentials of multiporphyrin assemblies showed the redox features of the constituted porphyrin monomers and supported weak interactions among the porphyrin units in noncovalent hexaporphyrin and dodecaporphyrin arrays.
    Inorganic Chemistry 10/2014; 53(20). DOI:10.1021/ic501569e · 4.76 Impact Factor
  • Emandi Ganapathi · Tamal Chatterjee · Mangalampalli Ravikanth ·
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    ABSTRACT: A simple route was developed for the synthesis of 9,10,19,20-tetraarylporphycenes by combining both McMurry and oxidative synthetic strategies and using readily available precursors. The desired 5,6-diaryldipyrroethenes, which were prepared in multigram quantities over two steps, were used to prepare 9,10,19,20-tetraarylporphycenes under mild acid-catalyzed conditions. As 5,6-diaryldipyrroethene precursors can easily be prepared in multigram quantities, this method is useful for the preparation of meso-tetrarylporphycenes that contain different aryl substituents. The molecular structures of these macrocycles were determined by HRMS analysis as well as 1D and 2D NMR studies. The tetraarylporphycenes exhibited a strong Soret band at approximately 380 nm and three Q bands in the region of 580–655 nm. The tetraarylprophycenes are reasonably fluorescent and stable under redox conditions.
    European Journal of Organic Chemistry 10/2014; 2014(30). DOI:10.1002/ejoc.201402770 · 3.07 Impact Factor
  • Tamal Chatterjee · Mangalampalli Ravikanth ·
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    ABSTRACT: The palladium(II) complex of calixoxasmaragdyrin was prepared in 80% yield by treating the free base calixoxasmaragdyrin with PdCl2 in CH3CN at reflux temperature. The crystal structure solved for Pd(II) calixoxasmaragdyrin indicates that the calixoxasmaragdyrin macrocycle is highly distorted and attained a boat shaped structure. The Pd(II) ion is coordinated to four pyrrolic nitrogens in square planar fashion, and it is placed at ∼0.138 Å above from the four coordinating pyrrole nitrogens plane (N1N2N3N4). The Pd-N bond lengths are inequivalent, and the Pd(II) ion is positioned more toward the dipyrromethane moiety of calixoxasmaragdyrin. The complex shows one broad absorption band at 477 nm and is not very stable under redox conditions. The Pd(II) calixoxasmaragdyrin showed good catalytic activity in the Suzuki-Miyaura cross coupling reactions.
    Inorganic Chemistry 09/2014; 53(19). DOI:10.1021/ic501595f · 4.76 Impact Factor
  • Emandi Ganapathi · Way-Zen Lee · Mangalampalli Ravikanth ·
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    ABSTRACT: The stable non-aromatic [20]dithiaporphyrin ( macrocycles were synthesized in decent yields by condensing readily available butene-2,3-diyl-bisthiophene-2,5-diyl-bis(p-methoxyphenylmethanol) with different meso-aryl dipyrromethanes under mild acid catalyzed conditions. The [20]dithiaporphyrin ( macrocycles are the first member of expanded porphyrin analogue of [18]dithiaporphyrin ( and consists two pyrroles and two thiophenes connected through five meso carbon bridges. The [20]dithiaporphyrin macrocycles were confirmed by mass, 1D and 2D NMR and X-ray crystallography. The X-ray structure revealed that the macrocycle is highly distorted and the two thiophene rings are completely out-of-plane from the "mean-plane" defined by the dipyrromethene moiety and the two meso carbons. In absorption spectrum, the macrocycles showed one strong band at ~420 nm and one weak band at ~720 nm. The electrochemical studies revealed that the macrocycles are stable under redox conditions. The metal sensing studies indicated that these macrocycles have potential to sense specific metal ions such as Hg2+ ion. Two covalently linked dithiahomoporphyrin-fluorophore dyads were synthesized by coupling iodo-functionalized dithiahomoporphyrin with ethynyl functionalized fluorophore such as boron-dipyrromethene (BODIPY) and BF2-smaragdyrin under mild Pd(0) coupling conditions. The potential of these dyads as fluorescent sensor for Hg2+ was explored and the studies indicated that both dyads can be used as fluorescent sensors.
    The Journal of Organic Chemistry 09/2014; 79(20). DOI:10.1021/jo501724d · 4.72 Impact Factor
  • Vellanki Lakshmi · Mangalampalli Ravikanth ·
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    ABSTRACT: A series of sterically crowded, mixed hexasubstituted BODIPYs containing two different types of substituents on the pyrrole carbons have been synthesized in high yields by a stepwise approach. The mixed BODIPYs were synthesized by bromination of BODIPYs followed by coupling with appropriate boronic acids under Suzuki coupling conditions. This approach has allowed the introduction of two different types of methyl/aryl substituents at the designated positions of the BODIPY core. All the hexasubstituted BODIPYs are readily soluble in common organic solvents and have been characterized by various spectral and electrochemical techniques. The spectral studies indicated that the presence of mixed methyl/aryl substituents on the BODIPY core significantly alters the electronic properties, and the electrochemical studies revealed that the BODIPYs are stable under redox conditions.
    European Journal of Organic Chemistry 09/2014; 2014(26). DOI:10.1002/ejoc.201402599 · 3.07 Impact Factor
  • Hemanta Kalita · Way-Zen Lee · Mangalampalli Ravikanth ·
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    ABSTRACT: The aromatic PO2 complexes of meso-triaryl-25-oxasmaragdyrins were synthesized by treating the free base 25-oxasmaragdyrins with POCl3 in toluene/triethylamine at refluxing temperature. The complexes are stable and characterized by X-ray and different spectroscopic techniques. In these complexes, the phosphorus(V) ion was bound to two pyrrolic nitrogen atoms of the smaragdyrin macrocycle and two oxygen atoms in tetrahedral geometry. The X-ray structure revealed that the smaragdyrin macrocycle showed significant distortion upon insertion of a PO2 unit, and the phosphorus atom lies 1.339 Å above the mean plane defined by three meso-carbon atoms of the macrocycle. These complexes absorb strongly in the visible region and are 2.5 times more strongly fluorescent than free base 25-oxasmaragdyrins. The smaragdyrin macrocycle becomes electron-deficient upon complexation with a PO2 unit because these complexes are easier to reduce but difficult to oxidize compared to free base smaragdyrins. We designed and synthesized a covalently linked BODIPY-PO2-smaragdyrin dyad and demonstrated efficient energy transfer from the BODIPY unit to the PO2-smaragdyrin unit.
    Inorganic Chemistry 08/2014; 53(17). DOI:10.1021/ic501629n · 4.76 Impact Factor

Publication Stats

2k Citations
575.57 Total Impact Points


  • 2001-2015
    • Indian Institute of Technology Bombay
      • • Department of Chemistry
      • • Centre for Research in Nanotechnology and Science (CRNTS)
      Mumbai, Maharashtra, India
    • Institute of Chemical Technology, Mumbai
      • Department of Chemistry
      Mumbai, Maharashtra, India
  • 2002-2014
    • Indian Institute of Technology Ropar
      • Department of Chemistry
      Rūpar, Punjab, India
  • 2000-2014
    • Maharashtra Institute of Technology
      Poona, Maharashtra, India
  • 2008
    • Indian Institute of Chemical Technology
      Bhaganagar, Telangana, India
  • 1993-2006
    • Indian Institute of Technology Kanpur
      • Department of Chemistry
      Cawnpore, Uttar Pradesh, India
  • 1999
    • Kyoto University
      • Division of Chemistry
      Kioto, Kyōto, Japan
  • 1995-1997
    • Tata Institute of Fundamental Research
      • Department of Chemical Sciences
      Mumbai, Maharashtra, India
  • 1996
    • Carnegie Mellon University
      • Department of Chemistry
      Pittsburgh, Pennsylvania, United States
  • 1994
    • Uttar Pradesh Textile Technology Institute
      Cawnpore, Uttar Pradesh, India