The Journal of Organic Chemistry
NOTE
Scheme 2. Degradation of Desethyl-VX on the Resin
(Run 17)
excess of fluoride and was derived from the slope of the plot of
ln[% OP] as a function of time. The % OP is the molar per-
centage of the OP in the mixture.
’ ASSOCIATED CONTENT
S
Supporting Information. NMR spectra, kinetic data, and
b
plots. This material is available free of charge via the Internet at
’ AUTHOR INFORMATION
Corresponding Author
*Tel: +972-8-9381453. Fax: +972-8-9381548. E-mail: yossiz@
iibr.gov.il; ishayc@iibr.gov.il.
constant (JPF = 956 Hz), different than that found for fluoro-
methylphosphonic acid or Et-G (JPF = 1045 Hz). The extremely
slowrateofdegradation of desethyl-VX as compared with VX may
be explained by its partial ionization in the basic medium of the
resin, which prevents the attack of any nucleophile anion like
fluoride or hydroxide.
In conclusion, toxic OP compounds (VX, GB, Et-G, and
desethyl-VX) can be degraded on Amberlite IRA 900 FÀ resin.
The advantage of this resin, in which the ammonium fluoride is
covalently bound to the solid support, over the alumina-supported
fluoride reagents8,9 is mainly expressed by its ability to degrade
VX in a catalytic mechanism. Moreover, during this catalytic process,
the toxic desethyl-VX is not formed in spite of the use of neutral
aqueous medium. These results designate this resin as a powerful
candidate for the building of active barriers in protective clothes,
filters, or column fillers mainly against “V” agents.
’ REFERENCES
(1) Wagner, G. W.; Bartram, P. W.; Koper, O.; Klabunde, K. J. J.
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(2) Wagner, G. W.; Koper, O.; Lucas, E.; Decker, S.; Klabunde, K. J.
J. Phys. Chem. B 2000, 104, 5118.
(3) Wagner, G. W.; Bartram, P. W. Langmuir 1999, 15, 8113.
(4) (a) Wagner, G. W.; Procell, L. R.; O’Connor, R. J.; Munavalli, S.;
Carnes, C. L.; Kapoor, P. N.; Klabunde, K. J. J. Am. Chem. Soc. 2001,
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C 2007, 111, 17564. (c) Saxena, A.; Sharma, A.; Srivastava, A. K.; Singh,
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(5) Wagner, G. W.; Chen, Q.; Wu, Y. J. Phys. Chem. C 2008,
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(6) Prasad, G. K.; Singh, B.; Ganesan, K.; Batra, A.; Kumeria, T.;
Gutch, P. K.; Vigayaraghavan, R. J. Hazard. Mater. 2009, 167, 1192.
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Takeuchi, K. J. Phys. Chem. C 2010, 114, 2305.
’ EXPERIMENTAL SECTION
Materials. The resin Amberlite IRA 900 FÀ (C6H4CH2N-
(CH3)3F, also named Fluoride on Amberlyst A-26, cat. no. 338879)
and its hydroxide (cat. no. 542571) and chloride (cat. no. 47060)
analogues were purchased from a commercial supplier.
(8) Gershonov, E.; Columbus, I.; Zafrani, Y. J. Org. Chem. 2009,
74, 8464.
(9) Zafrani, Y.; Goldvaser, M.; Dagan, S.; Feldberg, L.; Mizrahi, D.;
Waysbort, D.; Gershonov, E.; Columbus, I. J. Org. Chem. 2009, 74, 329.
(10) Bromberg, L.; Hatton, T. A. Ind. Eng. Chem. Res. 2005, 44, 7991.
(11) Bromberg, L.; Hatton, T. A. Ind. Eng. Chem. Res. 2007, 46, 3296.
(12) Bromberg, L.; Hatton, T. A. Polymer 2007, 48, 7490.
(13) Bao, Y. T.; Pitt, C. G. J. Polym. Sci. A: Polym. Chem. 1990, 28, 741.
(14) Hammond, P. S.; Forster, J. S. J. Appl. Polym. Sci. 1991,
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(15) Bromberg, L.; Schreuder-Gibson, H.; Creasy, W. R.; McGarvey,
D. J.; Fry, R. A.; Hatton, T. A. Ind. Eng. Chem. Res. 2009, 49, 1650.
(16) Gutch, P. K.; Singh, R.; Acharya, J. J. Appl. Polym. Sci. 2011,
121, 2250.
(17) Fringuelli, F.; Lanari, D.; Pizzo, F.; Vaccaro, L. Curr. Org. Synth.
2009, 6, 203.
(18) Sierakowski, T.; Kiddle, J. J. Tetrahedron Lett. 2005, 46, 2215.
(19) Bellamy, J. React. Polym. 1994, 23, 101.
(20) The number of VX equivalents are calculated versus the
number of fluoride ions in the resin, assuming 3 mmol/g fluoride.
(21) Columbus, I.; Waysbort, D.; Shmueli, L.; Nir, I.; Kaplan, D.
Environ. Sci. Technol. 2006, 40, 3952.
(22) When the amount of fluoride ions is in large excess compared
with the CWA, a pseudo-first-order kinetic was assumed for the
calculation of the half-life time of the CWA.
NMR. 31P and 19F MAS NMR spectra were obtained at 202
and 471 MHz, respectively, on a 11.7 T (500 MHz) spectro-
meter, equipped with a 0.4 cm standard CP-MAS probe, using
direct polarization (i.e., no cross-polarization (CP) was used).
Typical spinning rates were 5À7 kHz. Chemical shifts for 31P and
19F were referenced to external trimethyl phosphate (TMP) and
CFCl3, respectively, as 0 ppm. For 31P spectra, the pulse delay
was 2 s, which is considered sufficient for relaxation in OP esters
on solid matrices. The number of transients per spectrum was
200. For 19F spectra the pulse delay was 2 s, and the number of
transients per spectrum varied between 100 and 2000. For com-
parison purposes, spectra were recorded under identical conditions.
Sample Preparation. Caution: These experiments should only
be performed by trained personnel using applicable safety procedures.
Samples of the appropriate resin (2À32 mg) dry or swelled with
the appropriate amount of solvent (deuterated water, water,
acetonitrile, or ethanol) were added to the 0.4 cm ZrO2 rotor,
and 0.2À10 μL of the OP compound (VX, GB, Et-G, or desethyl-
VX) was applied via syringe to the center of the sample. The rotor
was sealed with a fitted Kel-F cap. 31P and 19F MAS NMR spectra
were measured periodically to determine remaining starting
material and identify degradation products.
(23) The identity of the degradation products (Et-G, EMPA,
DEMP, IMPA) was confirmed independently by comparison with
NMR of authentic samples.
(24) Munro, N. B.; Talmage, S. S.; Griffin, G. D.; Waters, L. C.;
Watson, A. P.; King, J. F.; Hauschild, V. Environ. Health Perspect. 1999,
107, 933.
The number of equivalents of each reactant was calculated
assuming a loading of 0.003 mmol/g fluoride on the resin. The
half-life time of any OP compound was calculated only for big
8552
dx.doi.org/10.1021/jo201600d |J. Org. Chem. 2011, 76, 8549–8553