The phototransformation of the herbicide Isopropyl carbanilate (IPC) has been investigated under UV light. Irradiation of the herbicide at room temperature in aqueous and organic solvents such as hexane and methanol afforded new photo-products formed as a consequence of various processes including photo-Fries rearrangement, ring solvolysis, hydrolysis of the amide/carbamoyl and ester bonds, ring coupling and polymerization. The percentage remaining of the herbicide as a function of time was followed periodically starting from zero time up to three hours. Analyses were performed by GC-FID equipped with a semipolar glass column operated at 170?C. The rate of photo disappearance of IPC under controlled lab condition followed 1st order kinetics and found to be solvent dependent in the manner of non polar > polar solvents. The photo-products were successfully separated by GC and preparative TLC (Silica gel F-254) and were identified using either GC-MS and/or MS. Identifications were assigned on the bases of molecular ions, mass fragmentation pattern and whenever possible by comparison with the mass spectra of literature analogues.
KeywordsPhototransformationIsopropyl carbanilateIsopropyl-N-PhenylcarbamateProphamIPC and GC-MS
K. A. Hassall, “The Biochemistry of Pesticides,” Mac-Millan Press Ltd., London, 1990, pp. 313-318.
I. R. Hill and S. J. L. Wright, “Pesticide Microbiology,” Academic Press, London, 1978, pp. 79-136.
G. G. Still and E. R. Mansager, “Aryl-Hydroxylation of Isopropyl 3-Chlorocarbanilate by Soybean Plants,” Phy-tochemistry, Vol. 11, No. 2, 1972, pp. 515-520. doi:10.1016/0031-9422(72)80006-2
H. D. Puurow, M. Canle, J. A. S. Palla and S. Steenken, “Reactions and Pathway Mechanism of Photodegradation of Pesticides,” Journal of Photochemistry and Photobi-ology, Vol. 67, No. 2, 2002, pp. 71-108.
C. Tomlin, “Pesticide Manual,” 10th Edition, British Crop Protection Council, Blackwell Science Publishing, Cam-bridge, 1994.
G. G. Still and R. A. Herrett, “Methylcarbamate, Carbani-late and Acylanilide,” In: P. C. Kearney and D. D. Kauf-man, Eds., Herbicides, Chemistry, Degradation and Mode of Action, Marcel Dekker Inc., New York, 1976.
C. M. Menzie, “Metabolism of Pesticides,” Updated II, Special Science Report, Wildlife No. 212, U.S. Depart-ment of Interior, Washington. D. C., 1978.
I.-S. You and R. Bartha, “Metabolism of 3,4-Dichloro- aniline by Pseudomonas Putida,” Journal of Agricultural and Food Chemistry, Vol. 30, No. 2, 1982, pp. 274-277. doi:10.1021/jf00110a014
J. L. Marty, T. Khafif, D. Vega and J. Bastida, “Degrada-tion of Phenylcarbamates by Pseudomonas Alcaligenes isolated from Soil,” Soil Biology and Biochemistry, Vol. 18, No. 6, 1986, pp. 649-653. doi:10.1016/0038-0717(86)90089-1
G. G. Still and E. R. Mansager, “Soybean Shoot Metabol-ism of Isopropyl 3-Chlorocarbanilate: Ortho and Para Aryl Hydroxylation,” Pesticide Biochemistry and Physiology, Vol. 3, No. 1, 1973, pp. 87-95. doi:10.1016/0048-3575(73)90013-8
D. Cole, “Oxidation of Xenobiotics in Plants,” In: D. H. Huston and T. R. Roberts, Eds., Progress in Pesticide Biochemistry and Toxicology, John Wiley and Sons, New York, Vol. 3, 1983; pp. 139-1446.
G. D. Paulson, A. M. Jacobsen, R. G. Zaylskie and V. J. Feil, “Isolation and Identification of Propham Metabolites from the Rat and Goat,” Journal of Agricultural and Food Chemistry, Vol. 21, No. 5, 1973, pp. 804-810. doi:10.1021/jf60189a008
C. C. Irving, “Enzymatic N-Hydroxylation of the Carci-nogen 2-Acetylaminofluorne and the Metabolism of N-Hydroxy- 2-Acetylamino-Fluorene-4-C14 in Vitro,” The Journal of Biological Chemistry, Vol. 239, 1964, p. 1589.
D. L. Heikes, “Mass Spectral Identification of a Metabolite of Chlorpropham in Potatoes,” Journal of Agricultural and Food Chemistry, Vol. 33, No. 2, 1985, pp. 246-249. doi:10.1021/jf00062a023
N. L. Wolfe, R. G. Zepp, D. F. Parris and G. L. Baughman, “Carbaryl, Propham and Chlorpropham: A Comparison of the Rates of Hydrolysis and Photolysis with the Rate of Biolysis,” Water Research, Vol. 12, No. 8, 1978, pp. 565-571. doi:10.1016/0043-1354(78)90134-3
L. C. Mitchell, “The Effect of Ultraviolet Light (2537A°) on 141 Pesticide Chemicals,” Journal of the Association of Official Agricultural Chemists, Vol. 44, 1961, pp. 643-712.
D. G. Crobsy, “Herbicide Photodecomposition,” In: D. C. Kearney and D. D. Kaufman, Eds., Herbicides, Chemistry Degradation and Mode of Action, Marcel Dekker, Inc., New York, Vol. 2, 1976, pp. 835-890.
G. W. Ware, “Review of Environment Contamination & Toxicology,” Google Books Results, 2000; pp. 113-116.
D. Masilamani and R. O. Hutchins, “Photoinduced Rear-rangement and Related Chemicals of Ethyl N-PhenylcarBamate,” The Journal of Organic Chemistry, Vol. 41, 9761, pp. 3687-3691.
W. Bahnemann, M. Muneer and M. Haque, “Titanium Photcatalysed Degradation of Selected Organic Pollutants in Aqueous Suspension,” Catalyst Today, Vol. 124, No. 3-4, 2007, pp. 133-148. doi:10.1016/j.cattod.2007.03.031
F. F. Guzik, “Photolysis of Isopropyl-N-3-Chloro-Car- bani-late in Water,” Journal of Agricultural and Food Chemistry, Vol. 26, No. 1, 1978, pp. 53-55. doi:10.1021/jf60215a026
aeru@herts.ac.uk /footprint, 2008.
T. Mill, “Chemical and Photochemical Oxidation,” In: O. Hutzinger, Ed., The Handbook of the Environmental Chemistry, Springer-Verlag, Berlin, 1980, pp. 77-104.
R. G. Zepp, “Experimental Approaches to Environmental Photochemistry,” In: O. Hutzinger, Ed., The Handbook of the Environmental Chemistry, Springer-Verlag, Berlin, 1982, pp. 19-42.
T. Mill, “Prediction of the Environmental Fate of Te-trachlorodibenzodioxin,” In: M. A. Kamrin and P. W. Rodgers, Eds., Dioxin in the Environment, Hemisphere Publ. Corp, Washington D. C., 1985; pp. 173-193.
D. R. Arnold and P. C. Wong, “The Photochemistry of Chloroaromatic Compunds,” Journal of the American Chemical Society, Vol. 99, No. 10, 1977, pp. 3361-3366. doi:10.1021/ja00452a029
G. Papageorigou and A. B. Corre, “Mechanism of Pho-to-Fries Photolysis of Carbamtes,” Photochemical & Photobiological Sciences, Vol. 4, 2005, pp. 216-220.
F. S. Tanaka, B. L. Hoffer and R. G. Wein, “Biphenyl Formation in the Photolysis of Aqueous Herbicide in Aqueous Media,” Pest Management Science, Vol. 16, 2006, pp. 265-270.
J. E. Herweh and C. E. Hoyle, “Photodegradation of Some Alkyl N-Phenylcarbamate,” The Journal of Organic Chemistry, Vol. 45, No. 11, 1980, pp. 2195-2201. doi:10.1021/jo01299a031
A. Kiss and D. Virag, “Photostability & Photodegradation Pathway of Distinctive Pesticides,” Journal of Environ-mental Quality, 2009, Vol. 38, No. 1, pp. 157-163. doi:10.2134/jeq2007.0504
E. Brillas, E. Mur, R. Sanleda, et al., “Aniline Mineraliza-tion by AOP’s: Anodic Oxidation, Photocatalysis, Elec-tro-Fenton and Photoelectro-Fenton Processes,” Applied Catalysis B: Environmental, 1998, Vol. 16, No. 1, pp. 31-42. doi:10.1016/S0926-3373(97)00059-3
E. S. Orejuela, “Determination of Propham and Chloro-propham in Postharvest Potatoes by LC with Chemilu-minescence Detection,” Analytical Letters, Vol. 37, No. 12, 2004, pp. 2531-2543. doi:10.1081/AL-200031123
M. Muneer, M. Qamar, M. Saquib and W. Bahnemann, “Heterogeneous Photocatalysed Reaction of Selected Pesticides in Aqueous Suspension of Titanium Dioxide,” Chemosphere, Vol. 61, No. 4, 2005, pp. 457-468. doi:10.1081/AL-200031123
A. Ozcan, Y. Sahin and M. Oturan, “Removal of Propham from Water by Electro-Fenton Technology, Kinetic and Mechanism,” Chemosphere, 2008, Vol. 73, No. 5, 737- 744. doi:10.1016/j.chemosphere.2008.06.027