The kinetics of oxidations of caffeine by permanganate ion in both perchloric and sulfuric acids solutions have been investigated spectrophotometrically at a constant ionic strength of 1.0 mol dm-3 and at 25°C. In both acids, the reaction-time curves were obtained with a sigmoid profile suggesting an autocatalytic effect caused by Mn(II) ions formed as a reaction product. Both catalytic and non-catalytic processes were determined to be first order with respect to the permanganate ion and caffeine concentrations, whereas the orders with respect to [H+] and [Mn(II)] were found to be less than unity. Variation of either ionic strength or dielectric constant of the medium had no significant effect on the oxidation rates. Spectroscopic studies and Michaelis-Menten plots showed no evidence for the formation of intermediate complexes in both acids suggesting that the reactions point towards the outer-sphere pathway. The reactions mechanism adequately describing the kinetic results was proposed. In both acids, the main oxidation products of caffeine were identified as 1,3,7-trimethyluric acid. Under comparable experimental conditions, the oxidation rate of caffeine in perchloric acid was slightly higher than that in sulfuric acid. The constants involved in the different steps of the reactions mechanism have been evaluated. With admiration to the rate-limiting step of these reactions, the activation parameters have been evaluated and discussed.
| Published in | Science Journal of Chemistry (Volume 4, Issue 2) |
| DOI | 10.11648/j.sjc.20160402.12 |
| Page(s) | 19-28 |
| Creative Commons |
This is an Open Access article, distributed under the terms of the Creative Commons Attribution 4.0 International License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use, distribution and reproduction in any medium or format, provided the original work is properly cited. |
| Copyright |
Copyright © The Author(s), 2016. Published by Science Publishing Group |
Caffeine, Oxidation, Permanganate, Acid, Kinetics, Mechanism
| [1] | Kittakoop P, Mahidol C, Ruchirawat S (2014) Alkaloids as important scaffolds in therapeutic drugs for the treatments of cancer, tuberculosis, and smoking cessation. Curr. Top. Med. Chem. 14: 239-252. |
| [2] | Cushnie TP, Cushnie B, Lamb AJ (2014) Recent advances in understanding the antibacterial properties of flavonoids. Int. J. Antimicrob. Agents 44: 377-386. |
| [3] | Qiu S, Sun H, Zhang AH, Xu HY, Yan GL, Han Y, Wang XJ (2014) Natural alkaloids: basic aspects, biological roles, and future perspectives. Chin. J. Nat. Med. 12: 401-406. |
| [4] | Ashihara H, Crozier A (2001) Caffeine: a well-known but little mentioned compound in plant science. TRENDS Plant Sci. 6: 407-413. |
| [5] | Parliment TH, Ho CT, Schieberle P (2000) Caffeinated Beverages: Health Benefits, Physiological Effects, and Chemistry. American Chemical Society symposium series ISSN 0097-6156; 754. |
| [6] | Nehlig A, Daval JL, Debry G (1992) Caffeine and the central nervous system: mechanisms of action, biochemical, metabolic and psychostimulant effects. Brain Res. Brain Res. Rev. 17: 139–70. |
| [7] | Bolton S (1981) Caffeine: Psychological Effects, Use and Abuse.Orthomolecular Psychiatry 10: 202–211. |
| [8] | Snel J, Lorist MM (2011) Effects of caffeine on sleep and cognition. Prog. Brain Res. Progress in Brain Research 190: 105–17. |
| [9] | Bishop D (2010) Dietary supplements and team-sport performance. Sports Med. 40: 995–1017. |
| [10] | Conger SA, Warren GL, Hardy MA, Millard-Stafford ML (2011) Does caffeine added to carbohydrate provide additional ergogenic benefit for endurance. Int. J. Sport Nut. Exerc. Metab. 21: 71–84. |
| [11] | Astorino TA, Roberson DW (2010) Efficacy of acute caffeine ingestion for short-term high-intensity exercise performance: a systematic review. J. Strength Cond. Res. 24: 257–65. |
| [12] | Nehlig A (2010) Is caffeine a cognitive enhancer? J. Alzheimers Dis. 20 Suppl. 1: S85–94. |
| [13] | Weinberg BA, Bealer BK (2001) The world of caffeine: the science and culture of the world’s most popular drug. Routledge Publication, New York. |
| [14] | Escohotado A, Symington K (1999) A Brief History of Drugs: From the Stone Age to the Stoned Age. Park Street Press. |
| [15] | Stewart R (1965) Oxidation in Organic Chemistry, Part A (ed.) Wiberg KB, New York, Academic Press. |
| [16] | Jose TP, Nandibewoor ST, Tuwar SM (2005) Mechanism of oxidation of L-histidine by heptavalent manganese in alkaline medium. E-J. Chem. 2: 75-85. |
| [17] | Fawzy A, Ashour S, Musleh MA (2014) Base-catalyzed oxidation of L-asparagine by alkaline permanganate and the effect of alkali-metal ion catalysts: kinetics and mechanistic approach. React. Kinet. Mech. Catal. 111: 443-460. |
| [18] | Fawzy A, Shaaban MR (2014) Kinetic and mechanistic investigations on the oxidation of N’-heteroaryl unsymmetrical formamidines by permanganate in aqueous alkaline medium. Transition Met. Chem. 39: 379-386. |
| [19] | Fawzy A, Zaafarany IA, Alfahemi J, Tirkistani FA (2015) Base-catalyzed oxidation of aminotriazole derivative by permanganate ion in aqueous alkaline medium: a kinetic study. Int. J. Inn. Res. Sci. Eng. Tech., 4: 6802-6814. |
| [20] | Asghar BH, Fawzy A (2014) Kinetic, mechanistic, and spectroscopic studies of permanganate oxidation of azinylformamidines in acidic medium, with autocatalytic behavior of manganese (II). J. Saudi Chem. Soc., in press. |
| [21] | Fawzy A, Ashour SS, Musleh MA (2014) Kinetics and mechanism of oxidation of L-histidine by permanganate ions in sulfuric acid medium. Int. J. Chem. Kinet. 46: 370-381. |
| [22] | Ahmed GA, Fawzy A, Hassan RM (2007) Spectrophotometric evidence for the formation of short-lived hypomanganate(V) and manganate(VI) transient species during the oxidation of K-carrageenan by alkaline permanganate. Carbohydr. Res., 342: 1382-1386. |
| [23] | Zaafarany IA, Fawzy A, Ahmed GA, Ibrahim SA, Hassan RM, Takagi HD (2010) Further evidence for detection of short-lived transient hypomanganate(V) and manganate(VI) intermediates during oxidation of some sulfated polysaccharides by alkaline permanganate using conventional spectrophotometeric techniques. Carbohydr. Res., 345: 1588-1593. |
| [24] | Hassan RM, Fawzy A, Alarifi A, Ahmed GA, Zaafarany IA, Takagi HD (2011) Base-catalyzed oxidation of some sulfated macromolecules: kinetics and mechanism of formation of intermediate complexes of short-lived manganate (VI) and/or hypomanganate (V) during oxidation of iota- and lambda-carrageenan polysaccharides by alkaline permanganate. J. Mol. Catal. A, 335: 38-45. |
| [25] | Hassan RM, Dahy A, Ibrahim S, Zaafarany IA, Fawzy A (2012) Oxidation of some macromolecules. Kinetics and mechanism of oxidation of methyl cellulose polysaccharide by permanganate ion in acid perchlorate solutions. Ind. Eng. Chem. Res., 51: 5424–5432. |
| [26] | Gardner KA, Kuehnert LL, Mayer JM (1997) Hydrogen atom abstraction by permanganate: oxidations of arylalkanes in organic solvents. Inorg. Chem., 36: 2069-2078. |
| [27] | Perez-Benito JF (2011) Permanganate oxidation of α-amino acids: kinetic correlations for the nonautocatalytic and autocatalytic reaction pathways. J. Phys. Chem. 115: 9876–9885. |
| [28] | Babatunde OA (2008) A study of the kinetics and mechanism of oxidation L-ascorbic acid by permanganate ion in acidic medium. World J. Chem. 3: 27–31. |
| [29] | Jayaram B, Mayanna SM (1983) Mechanism of oxidation of caffeine by sodium N-chlorobenzene: a kinetic study. Tetrahedron 39: 2271-2275. |
| [30] | Souza FS, Féris LA (2015) Degradation of caffeine by advanced oxidative processes: O3 and O3/UV, Ozone: Sci. Eng. 37: 379-384. |
| [31] | Kumar M, Adinarayana M (2000) Oxidation of caffeine by phosphate radical anion in aqueous solution under anoxic conditions. J. Chem. Sci. 112: 551-557. |
| [32] | Vogel I. A (1978) A Text book of quantitative inorganic analysis. 4th edn ELBS and Longman, New York, pp. 352; Feigl F (1975) Spot tests in organic analysis, 195 pp. Elsevier, New York. |
| [33] | Michaelis L, Menten ML (1913) The kinetics of invertase action. Biochem. Z. 49: 333–369. |
| [34] | Zahedi M, Bahrami H (2004) Kinetic and mechanism of autocatalytic oxidation of L-asperagine in moderately concentrated sulphuric acid medium. Kinet. Catal. 45: 351–358. |
| [35] | Hosahalli RV, Savanur AP, Nandibewoor ST, Chimatadar SA (2012) Kinetics and mechanism of the autocatalyzed oxidation of theophylline by permanganate in aqueous perchloric acid medium. J. Solution Chem. 41: 567–580. |
| [36] | Day MC, Selbin J (1985) Theoretical Inorganic Chemistry, Reinhold Publishing Corporation, New York, 1985, pp. 344. |
| [37] | Perez Benito JF, Mata Perez F, Brillas E (1987) Permanganate oxidation of glycine: Kinetics, catalytic effects, and mechanisms. Can. J. Chem. 65: 2329-2337. |
| [38] | Garrido JA, Perez Benito JF, Rodrigouez RM, Andrés JDe, Brillas E (1987) Autocatalysis by colloidal manganese dioxide in the permanganate oxidation of L-isoleucine. J. Chem. Res. 11: 380-381. |
| [39] | Abdel-Hamid MI, Khairou KS, Hassan RM (2003) Kinetics and mechanism of permanganate oxidation of pectin in acid perchlorate media. Eur. Polym. J. 39: 381–387. |
| [40] | Girgis MM, El-Shatoury SA, Khalil ZA (1985) Kinetics and mechanism of oxidation of lactic acid by KMnO4 in H2SO4 medium. Can. J. Chem. 63: 3317–3321. |
| [41] | Hassan RM, Fawzy A, Ahmed GA, Zaafarany IA, Asghar BS, Khairou KS (2009) Acid-catalyzed oxidation of some sulfated macromolecules. Kinetics and mechanism of oxidation of kappa-carrageenan polysaccharide by permanganate ion in acid perchlorate solutions. J. Mol. Catal. A: Chem. 309: 95–102. |
| [42] | Waters WA (1958) Rev. Chem. Soc. 12: 277-281. |
| [43] | Launer HF (1932) J. Am. Chem. Soc. 54: 2297–2302. |
| [44] | Wiberg KB (1965) Oxidation in Organic Chemistry, Part A, 48 pp. Academic Press, New York. |
| [45] | Chimatadar SA, Hiremath SC, Raju JR (1990) Oxidation of thallium (I) by permanganate in aqueous perchloric acid medium. Indian J. Chem. 30A: 190–192. |
| [46] | Bailar JC, Emeleus HJ, Nyholm R, Dickenson AFT (1975) Comprehensive Inorganic Chemistry, pp. 771, Pergamon Press Ltd., New York. |
| [47] | Frost AA, Person RG (1970) Kinetics and mechanism, Wiley Eastern, New Delhi, pp. 147. |
| [48] | Laidler K (1965) Chemical kinetics. McGraw-Hill, New York. |
| [49] | Farokhi SA, Nandibewoor ST (2004) The kinetic and mechanism of the oxidative decarboxylation of benzilic acid by acid permanganate (stopped flow technique) - autocatalytic study. Can. J. Chem. 82: 1372–1380. |
| [50] | Weissberger A (1974) In Investigation of rates and mechanism of reactions in techniques of chemistry, John Wiley & Sons (New York: Interscience Publication) pp. 421. |
APA Style
Ahmed Fawzy, Ishaq A. Zaafarany, Khalid S. Khairou, Layla S. Almazroai, Tahani M. Bawazeer, et al. (2016). Oxidation of Caffeine by Permanganate Ion in Perchloric and Sulfuric Acids Solutions: A Comparative Kinetic Study. Science Journal of Chemistry, 4(2), 19-28. https://doi.org/10.11648/j.sjc.20160402.12
ACS Style
Ahmed Fawzy; Ishaq A. Zaafarany; Khalid S. Khairou; Layla S. Almazroai; Tahani M. Bawazeer, et al. Oxidation of Caffeine by Permanganate Ion in Perchloric and Sulfuric Acids Solutions: A Comparative Kinetic Study. Sci. J. Chem. 2016, 4(2), 19-28. doi: 10.11648/j.sjc.20160402.12
AMA Style
Ahmed Fawzy, Ishaq A. Zaafarany, Khalid S. Khairou, Layla S. Almazroai, Tahani M. Bawazeer, et al. Oxidation of Caffeine by Permanganate Ion in Perchloric and Sulfuric Acids Solutions: A Comparative Kinetic Study. Sci J Chem. 2016;4(2):19-28. doi: 10.11648/j.sjc.20160402.12
Share This Article
Twitter
Linked In
Facebook
Copy
Download@article{10.11648/j.sjc.20160402.12,
author = {Ahmed Fawzy and Ishaq A. Zaafarany and Khalid S. Khairou and Layla S. Almazroai and Tahani M. Bawazeer and Badriah A. Al-Jahdali},
title = {Oxidation of Caffeine by Permanganate Ion in Perchloric and Sulfuric Acids Solutions: A Comparative Kinetic Study},
journal = {Science Journal of Chemistry},
volume = {4},
number = {2},
pages = {19-28},
doi = {10.11648/j.sjc.20160402.12},
url = {https://doi.org/10.11648/j.sjc.20160402.12},
eprint = {https://article.sciencepublishinggroup.com/pdf/10.11648.j.sjc.20160402.12},
abstract = {The kinetics of oxidations of caffeine by permanganate ion in both perchloric and sulfuric acids solutions have been investigated spectrophotometrically at a constant ionic strength of 1.0 mol dm-3 and at 25°C. In both acids, the reaction-time curves were obtained with a sigmoid profile suggesting an autocatalytic effect caused by Mn(II) ions formed as a reaction product. Both catalytic and non-catalytic processes were determined to be first order with respect to the permanganate ion and caffeine concentrations, whereas the orders with respect to [H+] and [Mn(II)] were found to be less than unity. Variation of either ionic strength or dielectric constant of the medium had no significant effect on the oxidation rates. Spectroscopic studies and Michaelis-Menten plots showed no evidence for the formation of intermediate complexes in both acids suggesting that the reactions point towards the outer-sphere pathway. The reactions mechanism adequately describing the kinetic results was proposed. In both acids, the main oxidation products of caffeine were identified as 1,3,7-trimethyluric acid. Under comparable experimental conditions, the oxidation rate of caffeine in perchloric acid was slightly higher than that in sulfuric acid. The constants involved in the different steps of the reactions mechanism have been evaluated. With admiration to the rate-limiting step of these reactions, the activation parameters have been evaluated and discussed.},
year = {2016}
}
TY - JOUR T1 - Oxidation of Caffeine by Permanganate Ion in Perchloric and Sulfuric Acids Solutions: A Comparative Kinetic Study AU - Ahmed Fawzy AU - Ishaq A. Zaafarany AU - Khalid S. Khairou AU - Layla S. Almazroai AU - Tahani M. Bawazeer AU - Badriah A. Al-Jahdali Y1 - 2016/05/03 PY - 2016 N1 - https://doi.org/10.11648/j.sjc.20160402.12 DO - 10.11648/j.sjc.20160402.12 T2 - Science Journal of Chemistry JF - Science Journal of Chemistry JO - Science Journal of Chemistry SP - 19 EP - 28 PB - Science Publishing Group SN - 2330-099X UR - https://doi.org/10.11648/j.sjc.20160402.12 AB - The kinetics of oxidations of caffeine by permanganate ion in both perchloric and sulfuric acids solutions have been investigated spectrophotometrically at a constant ionic strength of 1.0 mol dm-3 and at 25°C. In both acids, the reaction-time curves were obtained with a sigmoid profile suggesting an autocatalytic effect caused by Mn(II) ions formed as a reaction product. Both catalytic and non-catalytic processes were determined to be first order with respect to the permanganate ion and caffeine concentrations, whereas the orders with respect to [H+] and [Mn(II)] were found to be less than unity. Variation of either ionic strength or dielectric constant of the medium had no significant effect on the oxidation rates. Spectroscopic studies and Michaelis-Menten plots showed no evidence for the formation of intermediate complexes in both acids suggesting that the reactions point towards the outer-sphere pathway. The reactions mechanism adequately describing the kinetic results was proposed. In both acids, the main oxidation products of caffeine were identified as 1,3,7-trimethyluric acid. Under comparable experimental conditions, the oxidation rate of caffeine in perchloric acid was slightly higher than that in sulfuric acid. The constants involved in the different steps of the reactions mechanism have been evaluated. With admiration to the rate-limiting step of these reactions, the activation parameters have been evaluated and discussed. VL - 4 IS - 2 ER -
Email: