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Wang X, Pu L, Sun Z, Fang G, Wang Y, Gu C, Gao J. Comparative study of the photooxidation of arsenite mediated by dissolved and mineral-associated humic acid under light irradiation. JOURNAL OF HAZARDOUS MATERIALS 2024; 462:132759. [PMID: 37832435 DOI: 10.1016/j.jhazmat.2023.132759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 09/18/2023] [Accepted: 10/09/2023] [Indexed: 10/15/2023]
Abstract
The photochemical processes of dissolved humic acid and its potential contribution to As(III) oxidation in natural water has received considerable attention. However, the role of mineral-humic complexes in As(III) conversion is rarely studied. Herein, two simulated mineral-humic complexes were prepared by coating humic acid on hydrous aluminum oxide, HA@HAO, or montmorillonite, HA@SWy, respectively, and batch experiments at circumneutral pH were performed under light irradiation. Our findings showed that the light-assisted oxidation of As(III) increased with increasing fractions of organic carbon in mineral-humic complexes, and As(III) photooxidation with HA@HAO or HA@SWy was up to 18.2 or 3.5-fold higher compared to that measured in the presence of equivalent amount of free HA, respectively. The reactive triplet state of HA and hydroxyl radicals in HA@HAO and HA@SWy system made a primary contribution to As(III) oxidation under irradiation. The results indicated that mineral-humic complexes have dual roles, an adsorbent and a photosensitizer, to promote As(III) access to reactive intermediates at the particle surfaces. This process was important for As(III) conversion in paddy water as colloidal particles, composed of both minerals and HA, could greatly promote As(III) oxidation and As(V) immobilization. This study provides a previously overlooked, important mechanism of As(III) phototransformation mediated by mineral-associated humic acid in natural environment.
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Affiliation(s)
- Xinghao Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Lirong Pu
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Zhaoyue Sun
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Guodong Fang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yujun Wang
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Cheng Gu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, China
| | - Juan Gao
- Key Laboratory of Soil Environment and Pollution Remediation, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Nanjing 211135, China.
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2
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Chiş V, Vinţeler E. Excitation energies for anionic drugs predicted by PBE0, TPSS and τHCTH density functionals. J Mol Struct 2021. [DOI: 10.1016/j.molstruc.2021.131120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022]
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3
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Roy B, Roy S, Kundu M, Maji S, Pal B, Mandal M, Singh NDP. Ground-State Proton-Transfer (GSPT)-Assisted Enhanced Two-Photon Uncaging from a Binol-based AIE-Fluorogenic Phototrigger. Org Lett 2021; 23:2308-2313. [PMID: 33689383 DOI: 10.1021/acs.orglett.1c00445] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
We demonstrated for the first time without any chemical modification the two-photon absorption (TPA) cross-section can be enhanced and red-shifted to the near-infrared (NIR) region by the ground-state proton-transfer (GSPT) process. Using GSPT, we developed a simple binol-based aggregation-induced emission (AIE)-fluorogenic phototrigger having a large two-photon uncaging cross-section in the "phototherapeutic window". As a proof of concept, we showed our phototrigger for the release of two different anticancer drugs in the NIR region.
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Affiliation(s)
- Biswajit Roy
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Samrat Roy
- Department of Physics, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India
| | - Moumita Kundu
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Somnath Maji
- Department of Biotechnology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - Bipul Pal
- Department of Physics, Indian Institute of Science Education and Research Kolkata, Mohanpur, West Bengal 741246, India
| | - Mahitosh Mandal
- School of Medical Science and Technology, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
| | - N D Pradeep Singh
- Department of Chemistry, Indian Institute of Technology Kharagpur, Kharagpur 721302, India
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4
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Field T, Peterson J, Ma C, Jagadesan P, Da Silva JP, Rubina M, Ramamurthy V, Givens RS. Competing pathways for photoremovable protecting groups: the effects of solvent, oxygen and encapsulation. Photochem Photobiol Sci 2020; 19:1364-1372. [DOI: 10.1039/d0pp00067a] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Photolysis of p-hydroxyphenacyloxy arenes releases free phenols in good yields governed by their pKa. At high pKa, new byproducts (Bvs. A) reveal a change in reaction mechanism.
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Affiliation(s)
- Thomas Field
- Department of Chemistry
- University of Kansas
- Lawrence
- USA
| | | | - Chicheng Ma
- Department of Chemistry
- University of Kansas
- Lawrence
- USA
| | | | - José P. Da Silva
- CCMAR - Centre of Marine Sciences
- University of Algarve
- Campus de Gambelas
- Portugal
| | - Marina Rubina
- Department of Chemistry
- University of Kansas
- Lawrence
- USA
| | - V. Ramamurthy
- Department of Chemistry
- University of Miami
- Coral Gables
- USA
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5
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Ngoy BP, May AK, Mack J, Nyokong T. Optical Limiting and Femtosecond Pump-Probe Transient Absorbance Properties of a 3,5-distyrylBODIPY Dye. Front Chem 2019; 7:740. [PMID: 31737610 PMCID: PMC6834545 DOI: 10.3389/fchem.2019.00740] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2019] [Accepted: 10/16/2019] [Indexed: 12/22/2022] Open
Abstract
The optical limiting (OL) properties of a 3,5-di-p-benzyloxystyrylBODIPY dye with an p-acetamidophenyl moiety at the meso-position have been investigated by using the open-aperture Z-scan technique at 532 nm with 10 ns laser pulses. There is a ca. 140 nm red shift of the main spectral band to 644 nm relative to the corresponding BODIPY core dye, due to the incorporation of p-benzyloxystyryl groups at the 3,5-positions. As a result, there is relatively weak absorbance across most of the visible region under ambient light conditions. Analysis of the observed reverse saturable absorbance (RSA) profiles demonstrates that the dye is potentially suitable for use in optical limiting applications as has been reported previously for other 3,5-distyrylBODIPY dyes. Time-resolved transient absorption spectroscopy and kinetic studies with femtosecond and nanosecond scale laser pulses provide the first direct spectral evidence that excited state absorption (ESA) from the S1 state is responsible for the observed OL properties.
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Affiliation(s)
- Bokolombe P. Ngoy
- Department of Chemistry, Institute for Nanotechnology Innovation, Rhodes University, Makhanda, South Africa
- Département de Chimie, Université de Kinshasa, Kinshasa, Democratic Republic of the Congo
| | - Aviwe K. May
- Department of Chemistry, Institute for Nanotechnology Innovation, Rhodes University, Makhanda, South Africa
| | - John Mack
- Department of Chemistry, Institute for Nanotechnology Innovation, Rhodes University, Makhanda, South Africa
| | - Tebello Nyokong
- Department of Chemistry, Institute for Nanotechnology Innovation, Rhodes University, Makhanda, South Africa
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6
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Torti E, Havel V, Yawer MA, Ludvíková L, Babiak M, Klán P, Sindelar V. Supramolecular Storage and Controlled Photorelease of an Oxidizing Agent using a Bambusuril Macrocycle. Chemistry 2017; 23:16768-16772. [DOI: 10.1002/chem.201704948] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2017] [Indexed: 11/08/2022]
Affiliation(s)
- Edoardo Torti
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Václav Havel
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Mirza A. Yawer
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Lucie Ludvíková
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Michal Babiak
- CEITEC-Central European Institute of Technology and National Centre for Biomolecular Research; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Petr Klán
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
| | - Vladimir Sindelar
- Department of Chemistry & RECETOX, Faculty of Science; Masaryk University; Kamenice 5 625 00 Brno Czech Republic
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7
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Houk AL, Givens RS, Elles CG. Two-Photon Activation of p-Hydroxyphenacyl Phototriggers: Toward Spatially Controlled Release of Diethyl Phosphate and ATP. J Phys Chem B 2016; 120:3178-86. [PMID: 26962676 DOI: 10.1021/acs.jpcb.5b12150] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023]
Abstract
Two-photon activation of the p-hydroxyphenacyl (pHP) photoactivated protecting group is demonstrated for the first time using visible light at 550 nm from a pulsed laser. Broadband two-photon absorption measurements reveal a strong two-photon transition (>10 GM) near 4.5 eV that closely resembles the lowest-energy band at the same total excitation energy in the one-photon absorption spectrum of the pHP chromophore. The polarization dependence of the two-photon absorption band is consistent with excitation to the same S3 ((1)ππ*) excited state for both one- and two-photon activation. Monitoring the progress of the uncaging reaction under nonresonant excitation at 550 nm confirms a quadratic intensity dependence and that two-photon activation of the uncaging reaction is possible using visible light in the range 500-620 nm. Deprotonation of the pHP chromophore under mildly basic conditions shifts the absorption band to lower energy (3.8 eV) in both the one- and two-photon absorption spectra, suggesting that two-photon activation of the pHP chromophore may be possible using light in the range 550-720 nm. The results of these measurements open the possibility of spatially and temporally selective release of biologically active compounds from the pHP protecting group using visible light from a pulsed laser.
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Affiliation(s)
- Amanda L Houk
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
| | - Richard S Givens
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
| | - Christopher G Elles
- Department of Chemistry, University of Kansas , Lawrence, Kansas 66045, United States
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8
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Al Anshori J, Slanina T, Palao E, Klán P. The internal heavy-atom effect on 3-phenylselanyl and 3-phenyltellanyl BODIPY derivatives studied by transient absorption spectroscopy. Photochem Photobiol Sci 2016; 15:250-9. [PMID: 26790756 DOI: 10.1039/c5pp00366k] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Three monosubstituted 3-phenylselanyl and 3-phenyltellanyl BODIPY derivatives were synthesized and their spectroscopic properties were characterized and compared to those of iodine and chlorine-atoms containing analogues as well as an unsubstituted BODIPY derivative. The fluorescence quantum yields were found to decrease, whereas the intersystem crossing quantum yields (ΦISC), determined by transient spectroscopy, increased in the order of the H → Cl → Se/I → Te substitution. The maximum ΦISC, found for the 3-phenyltellanyl derivative, was 59%. The results are interpreted in terms of the internal heavy-atom effect of the substituents.
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Affiliation(s)
- Jamaludin Al Anshori
- RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic.
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9
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Slanina T, Šebej P, Heckel A, Givens RS, Klán P. Caged Fluoride: Photochemistry and Applications of 4-Hydroxyphenacyl Fluoride. Org Lett 2015; 17:4814-7. [DOI: 10.1021/acs.orglett.5b02374] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Affiliation(s)
- Tomáš Slanina
- Department
of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Peter Šebej
- Department
of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
| | - Alexander Heckel
- Institute
for Organic Chemistry and Chemical Biology, Goethe-University Frankfurt, Max-von-Laue-Str. 9, 60438 Frankfurt, Germany
| | - Richard S. Givens
- Department
of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, 5010 Malott
Hall, Lawrence, Kansas 66045, United States
| | - Petr Klán
- Department
of Chemistry and RECETOX, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic
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10
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Bownik I, Šebej P, Literák J, Heger D, Šimek Z, Givens RS, Klán P. 4-Hydroxyphenacyl Ammonium Salts: A Photoremovable Protecting Group for Amines in Aqueous Solutions. J Org Chem 2015; 80:9713-21. [DOI: 10.1021/acs.joc.5b01770] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Affiliation(s)
| | | | | | | | | | - Richard S. Givens
- Department
of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, 5010 Malott
Hall, Lawrence, Kansas 66045, United States
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11
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Kirmess KM, Knochenmuss R, Blanchard GJ, Kinsel GR. Excited state dynamics in the matrix-assisted laser desorption/ionization matrix 2,4,6-trihydroxyacetophenone: evidence for triplet pooling charge separation reactions. RAPID COMMUNICATIONS IN MASS SPECTROMETRY : RCM 2014; 28:2134-2140. [PMID: 25156603 DOI: 10.1002/rcm.7000] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/06/2014] [Revised: 07/25/2014] [Accepted: 07/26/2014] [Indexed: 06/03/2023]
Abstract
RATIONALE Excited state pooling reactions are a central part of some models of ultraviolet matrix-assisted laser desorption/ionization (MALDI) mechanisms. Evidence has been found for pooling in several matrix materials, but a recent report of pure exponential fluorescence decay at MALDI-relevant laser fluences suggested that 2,4,6-trihydroxy-acetophenone (THAP) may be an example of a matrix in which pooling does not occur (Lin et al., Rapid Commun. Mass Spectrom. 2014, 28, 77). However, those data were instrumentally limited in dynamic range and signal/noise ratio, and the conclusion does not take into account several aspects of THAP excited state dynamics. METHODS Using time-correlated single photon counting, and absorption and emission spectroscopies, the excited state dynamics of THAP are reexamined. RESULTS Like many other aromatic ketones and acetophenone, isolated THAP molecules undergo very efficient intersystem crossing. No fluorescence is observed in dilute solution. In the solid state, efficient fluorescence reappears, but is non-exponential even at very low excitation intensity. The solvent used for sample preparation was found to have a large effect on the spectra and decay curves. Needle-like crystals seem to be correlated with reduced intersystem crossing. CONCLUSIONS THAP solid state fluorescence is entirely due to intermolecular interactions. Activation of fluorescence, instead of quenching, is a clear indicator of delocalized excited state phenomena in THAP. Contrary to the conclusions of Lin et al., the greatly increased singlet lifetime in the solid state substantially increases the probability that pooling-type reactions are indeed involved in ionization processes. The sensitivity of fluorescence and phosphorescence on sample morphology appears to reflect changes in intermolecular interactions due to crystal packing. Pooling charge separation pathways based on known triplet-triplet ionization reactions of aromatic ketones are proposed.
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Affiliation(s)
- Kristopher M Kirmess
- Department of Chemistry and Biochemistry, Southern Illinois University at Carbondale, Carbondale, IL, 62901, USA
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12
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Šolomek T, Heger D, Ngoy BP, Givens RS, Klán P. The Pivotal Role of Oxyallyl Diradicals in Photo-Favorskii Rearrangements: Transient Spectroscopic and Computational Studies. J Am Chem Soc 2013; 135:15209-15. [DOI: 10.1021/ja407588p] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Affiliation(s)
| | | | | | - Richard S. Givens
- Department of Chemistry, University of Kansas, 1251 Wescoe Hall
Drive, 5010 Malott Hall, Lawrence, Kansas 66045, United States
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13
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Kammath VB, Šolomek T, Ngoy BP, Heger D, Klán P, Rubina M, Givens RS. A photo-Favorskii ring contraction reaction: the effect of ring size. J Org Chem 2013; 78:1718-29. [PMID: 22686289 PMCID: PMC3502675 DOI: 10.1021/jo300850a] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The effect of ring size on the photo-Favorskii induced ring-contraction reaction of the hydroxybenzocycloalkanonyl acetate and mesylate esters (7a-d, 8a-c) has provided new insight into the mechanism of the rearrangement. By monotonically decreasing the ring size in these cyclic derivatives, the increasing ring strain imposed on the formation of the elusive bicyclic spirocyclopropanone 20 results in a divergence away from rearrangement and toward solvolysis. Cycloalkanones of seven or eight carbons undergo a highly efficient photo-Favorskii rearrangement with ring contraction paralleling the photochemistry of p-hydroxyphenacyl esters. In contrast, the five-carbon ring does not rearrange but is diverted to the photosolvolysis channel avoiding the increased strain energy that would accompany the formation of the spirobicyclic ketone, the "Favorskii intermediate 20". The six-carbon analogue demonstrates the bifurcation in reaction channels, yielding a solvent-sensitive mixture of both. Employing a combination of time-resolved absorption measurements, quantum yield determinations, isotopic labeling, and solvent variation studies coupled with theoretical treatment, a more comprehensive mechanistic description of the rearrangement has emerged.
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Affiliation(s)
- Viju Balachandran Kammath
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A8, 625 00 Brno, Czech Republic
| | - Tomáš Šolomek
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A8, 625 00 Brno, Czech Republic
- Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Kamenice 126/3, 625 00 Brno, Czech Republic
| | - Bokolombe Pitchou Ngoy
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A8, 625 00 Brno, Czech Republic
- Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Kamenice 126/3, 625 00 Brno, Czech Republic
| | - Dominik Heger
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A8, 625 00 Brno, Czech Republic
- Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Kamenice 126/3, 625 00 Brno, Czech Republic
| | - Petr Klán
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5/A8, 625 00 Brno, Czech Republic
- Research Centre for Toxic Compounds in the Environment, Faculty of Science, Masaryk University, Kamenice 126/3, 625 00 Brno, Czech Republic
| | - Marina Rubina
- Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, 5010 Malott Hall, 66045 Lawrence, Kansas, United States
| | - Richard S. Givens
- Department of Chemistry, University of Kansas, 1251 Wescoe Hall Drive, 5010 Malott Hall, 66045 Lawrence, Kansas, United States
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Klán P, Šolomek T, Bochet CG, Blanc A, Givens R, Rubina M, Popik V, Kostikov A, Wirz J. Photoremovable protecting groups in chemistry and biology: reaction mechanisms and efficacy. Chem Rev 2013; 113:119-91. [PMID: 23256727 PMCID: PMC3557858 DOI: 10.1021/cr300177k] [Citation(s) in RCA: 1242] [Impact Index Per Article: 112.9] [Reference Citation Analysis] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2012] [Indexed: 02/06/2023]
Affiliation(s)
- Petr Klán
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00 Brno, Czech Republic.
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15
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Ngoy BP, Sebej P, Solomek T, Lim BH, Pastierik T, Park BS, Givens RS, Heger D, Klán P. 2-Hydroxyphenacyl ester: a new photoremovable protecting group. Photochem Photobiol Sci 2012; 11:1465-75. [PMID: 22766787 DOI: 10.1039/c2pp25133g] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A 2-hydroxyphenacyl moiety absorbing below 370 nm is proposed as a new photoremovable protecting group for carboxylates and sulfonates. Laser flash photolysis and steady-state sensitization studies show that the leaving group is released from a short-lived triplet state. In addition, DFT-based quantum chemical calculations were performed to determine the key reaction steps. We found that triplet excited state intramolecular proton transfer represents a major deactivation channel. Minor productive pathways involving the triplet anion and quinoid triplet enol intermediates have also been identified.
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Affiliation(s)
- Bokolombe Pitchou Ngoy
- Department of Chemistry, Faculty of Science, Masaryk University, Kamenice 5, 625 00, Brno, Czech Republic
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