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Sivaguru J, Selvaraj M, Ravi S, Park H, Song CW, Chun HH, Ha CS. Diamine Functionalized Cubic Mesoporous Silica for Ibuprofen Controlled Delivery. JOURNAL OF NANOSCIENCE AND NANOTECHNOLOGY 2015; 15:4784-4791. [PMID: 26373038 DOI: 10.1166/jnn.2015.9811] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/05/2023]
Abstract
A diamine functionalized cubic mesostructured KIT-6 (N-KIT-6) has been prepared by post-synthetic method using calcined mesoporous KIT-6 with a diamine source, i.e., N-'[3-(tri methoxysilyl)- propyl]'ethylenediamine. The KIT-6 mesoporous silica used for N-KIT-6 was synthesized under weak acidic hydrothermal method using bitemplates, viz., Pluronic P123 and 1-butanol. The synthesized mesoporous materials, KIT-6 and N-KIT-6, have been characterized by the relevant instrumental techniques such as SAXS, N2 sorption isotherm, FT-IR, SEM, TEM and TGA to prove the standard mesoporous materials with the identification of diamine groups. The characterized mesoporous materials, KIT-6 and N-KIT-6, have been extensively used in the potential application of controlled drug delivery, where ibuprofen (IBU) employed as a model drug. The rate of IBU adsorption and release was monitored by UV vis-spectrometer. On the basis of the experimental results of controlled drug delivery system, the results of IBU adsorption and releasing rate in N-KIT-6 are higher than those of KIT-6 because of the higher hydrophobic nature as well as rich basic sites on the surface of inner pore wall silica.
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Vallavoju N, Sivaguru J. Supramolecular photocatalysis: combining confinement and non-covalent interactions to control light initiated reactions. Chem Soc Rev 2015; 43:4084-101. [PMID: 24705505 DOI: 10.1039/c3cs60471c] [Citation(s) in RCA: 152] [Impact Index Per Article: 16.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
Using non-bonding interactions to control photochemical reactions requires an understanding of not only thermodynamics and kinetics of ground state and excited state processes but also the intricate interactions that dictate the dynamics within the system of interest. This review is geared towards a conceptual understanding of how one can control the reactivity and selectivity in the excited state by employing confinement and non-covalent interactions. Photochemical reactivity of organic molecules within confined containers and organized assemblies as well as organic templates that interact through H-bonding and/or cation-carbonyl/cation-π interactions is reviewed with an eye towards understanding supramolecular effects and photocatalysis.
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Rajendran S, Raghunathan R, Hevus I, Krishnan R, Ugrinov A, Sibi MP, Webster DC, Sivaguru J. Inside Back Cover: Programmed Photodegradation of Polymeric/Oligomeric Materials Derived from Renewable Bioresources (Angew. Chem. Int. Ed. 4/2015). Angew Chem Int Ed Engl 2015. [DOI: 10.1002/anie.201411878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Rajendran S, Raghunathan R, Hevus I, Krishnan R, Ugrinov A, Sibi MP, Webster DC, Sivaguru J. Innenrücktitelbild: Programmed Photodegradation of Polymeric/Oligomeric Materials Derived from Renewable Bioresources (Angew. Chem. 4/2015). Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201411878] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
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Clay A, Kumarasamy E, Ayitou AJL, Sivaguru J. Photochemistry of Atropisomers: Non-biaryl Atropisomers for Stereospecific Phototransformations. CHEM LETT 2014. [DOI: 10.1246/cl.140819] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/20/2022]
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Vallavoju N, Selvakumar S, Jockusch S, Prabhakaran MT, Sibi MP, Sivaguru J. Corrigendum: Evaluating Thiourea Architecture for Intramolecular [2+2] Photocycloaddition of 4-Alkenylcoumarins. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400949] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
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Rajendran S, Raghunathan R, Hevus I, Krishnan R, Ugrinov A, Sibi MP, Webster DC, Sivaguru J. Programmed Photodegradation of Polymeric/Oligomeric Materials Derived from Renewable Bioresources. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201408492] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
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Rajendran S, Raghunathan R, Hevus I, Krishnan R, Ugrinov A, Sibi MP, Webster DC, Sivaguru J. Programmed Photodegradation of Polymeric/Oligomeric Materials Derived from Renewable Bioresources. Angew Chem Int Ed Engl 2014; 54:1159-63. [DOI: 10.1002/anie.201408492] [Citation(s) in RCA: 79] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2014] [Indexed: 11/10/2022]
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Vallavoju N, Selvakumar S, Jockusch S, Prabhakaran MT, Sibi MP, Sivaguru J. Evaluating Thiourea Architecture for Intramolecular [2+2] Photocycloaddition of 4-Alkenylcoumarins. Adv Synth Catal 2014. [DOI: 10.1002/adsc.201400677] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Iyer A, Jockusch S, Sivaguru J. Dictating Photoreactivity through Restricted Bond Rotations: Cross-Photoaddition of Atropisomeric Acrylimide Derivatives under UV/Visible-Light Irradiation. J Phys Chem A 2014; 118:10596-602. [DOI: 10.1021/jp505678b] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/23/2023]
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61
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Kumarasamy E, Raghunathan R, Jockusch S, Ugrinov A, Sivaguru J. Tailoring Atropisomeric Maleimides for Stereospecific [2 + 2] Photocycloaddition—Photochemical and Photophysical Investigations Leading to Visible-Light Photocatalysis. J Am Chem Soc 2014; 136:8729-37. [DOI: 10.1021/ja5034638] [Citation(s) in RCA: 68] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
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Vallavoju N, Selvakumar S, Jockusch S, Sibi MP, Sivaguru J. Enantioselective Organo-Photocatalysis Mediated by Atropisomeric Thiourea Derivatives. Angew Chem Int Ed Engl 2014. [DOI: 10.1002/ange.201310940] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Vallavoju N, Selvakumar S, Jockusch S, Sibi MP, Sivaguru J. Enantioselective organo-photocatalysis mediated by atropisomeric thiourea derivatives. Angew Chem Int Ed Engl 2014; 53:5604-8. [PMID: 24740511 DOI: 10.1002/anie.201310940] [Citation(s) in RCA: 140] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2013] [Revised: 02/12/2014] [Indexed: 11/09/2022]
Abstract
Can photocatalysis be performed without electron or energy transfer? To address this, organo-photocatalysts that are based on atropisomeric thioureas and display lower excited-state energies than the reactive substrates have been developed. These photocatalysts were found to be efficient in promoting the [2+2] photocycloaddition of 4-alkenyl-substituted coumarins, which led to the corresponding products with high enantioselectivity (77-96% ee) at low catalyst loading (1-10 mol%). The photocatalytic cycle proceeds by energy sharing via the formation of both static and dynamic complexes (exciplex formation), which is aided by hydrogen bonding.
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Ayitou AJL, Clay A, Kumarasamy E, Jockusch S, Sivaguru J. Enantiospecific photochemical 6π-ring closure of α-substituted atropisomeric acrylanilides – role of alkali metal ions. Photochem Photobiol Sci 2014; 13:141-4. [DOI: 10.1039/c3pp50278c] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pemberton BC, Ugrinov A, Sivaguru J. Evaluating photodimerization of 6-methylcoumarin mediated by cucurbit[8]uril through mechanical grinding – Supramolecular effects of additives. J Photochem Photobiol A Chem 2013. [DOI: 10.1016/j.jphotochem.2013.01.005] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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Ayitou AJL, Fukuhara G, Kumarasamy E, Inoue Y, Sivaguru J. Enantiospecific Photochemical Transformations under Elevated Pressure. Chemistry 2013; 19:4327-34. [DOI: 10.1002/chem.201203665] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2012] [Indexed: 11/10/2022]
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Raghunathan R, Kumarasamy E, Iyer A, Ugrinov A, Sivaguru J. Intramolecular Paternò–Büchi reaction of atropisomeric α-oxoamides in solution and in the solid-state. Chem Commun (Camb) 2013; 49:8713-5. [DOI: 10.1039/c3cc44281k] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Kumarasamy E, Sivaguru J. Light-induced stereospecific intramolecular [2+2]-cycloaddition of atropisomeric 3,4-dihydro-2-pyridones. Chem Commun (Camb) 2013; 49:4346-8. [DOI: 10.1039/c2cc37123e] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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Pemberton BC, Raghunathan R, Volla S, Sivaguru J. From Containers to Catalysts: Supramolecular Catalysis within Cucurbiturils. Chemistry 2012; 18:12178-90. [DOI: 10.1002/chem.201202083] [Citation(s) in RCA: 144] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
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Kumarasamy E, Jesuraj JL, Omlid JN, Ugrinov A, Sivaguru J. Light-Induced Enantiospecific 4π Ring Closure of Axially Chiral 2-Pyridones: Enthalpic and Entropic Effects Promoted by H-Bonding. J Am Chem Soc 2011; 133:17106-9. [DOI: 10.1021/ja203087a] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Ayitou A, Pemberton BC, Kumarasamy E, Vallavoju N, Sivaguru J. Fun with Photons: Selective Light Induced Reactions in Solution and in Water Soluble Nano-containers. Chimia (Aarau) 2011; 65:202-9. [DOI: 10.2533/chimia.2011.202] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/19/2022] Open
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Pemberton BC, Kumarasamy E, Jockusch S, Srivastava DK, Sivaguru J. Photophysical aspects of 6-methylcoumarin–cucurbit[8]uril host–guest complexes. CAN J CHEM 2011. [DOI: 10.1139/v10-121] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Photophysical measurements of 6-methylcoumarin (1) encapsulated within cucurbit[8]uril (CB[8]) indicate a pronounced red shift in the fluorescence maximum with an increase in the emission quantum yield and fluorescence lifetime. In addition, at 77 K, there is observable phosphorescence upon encapsulation within CB[8]. The photophysical measurements add credibility to our previously proposed dynamic nature of the CB–coumarin complex in solution. The dynamic nature of the CB[8]–coumarin host–guest complex in water is critical to a CB acting as a supramolecular catalytic nanoreaction vessel to facilitate the photodimerization of coumarins leading to syn dimers.
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Pemberton BC, Singh RK, Johnson AC, Jockusch S, Da Silva JP, Ugrinov A, Turro NJ, Srivastava DK, Sivaguru J. Supramolecular photocatalysis: insights into cucurbit[8]uril catalyzed photodimerization of 6-methylcoumarin. Chem Commun (Camb) 2011; 47:6323-5. [DOI: 10.1039/c1cc11164g] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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74
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Ayitou AJL, Sivaguru J. Reactive spin state dependent enantiospecific photocyclization of axially chiral α-substituted acrylanilides. Chem Commun (Camb) 2011; 47:2568-70. [DOI: 10.1039/c0cc04416d] [Citation(s) in RCA: 36] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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75
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Ayitou AJL, Vallavoju N, Ugrinov A, Sivaguru J. Enantiospecific 6π-photocyclization of atropisomeric α-substituted acrylanilides in the solid-state: role of crystalline confinement on enantiospecificity. Photochem Photobiol Sci 2011; 10:1380-3. [DOI: 10.1039/c1pp05057e] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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