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Decontamination waste from chemical weapons (CW) agents has been stored in ton containers on Johnston Atoll since 1971. The waste was recently sampled and analyzed to determine its chemical composition in preparation for disposal. Due to the range of products and analytical requirements, multiple chromatographic and spectroscopic methods were necessary, including gas chromatography/mass spectrometry (GC/MS), gas chromatography/atomic emission detection (GC/AED), liquid chromatography/mass spectrometry (LC/MS), capillary electrophoresis (CE), and nuclear magnetic resonance spectroscopy (NMR). The samples were screened for residual agents. No residual sarin (GB) or VX was found to detection limits of 20 ng/mL, but 3% of the samples contained residual sulfur mustard (HD) at

Two series of 2,4,6-triphenylverdazyls substituted at the C(3) position of the heterocyclic ring are obtained using new convenient synthetic methodology. Thus, crown ether assisted solid–liquid phase-transfer catalysis promotes the formation of 3-n-alkyl-substituted 2,4,6-triphenylverdazyls in the reactions of 1,3,5-triphenylformazan with n-alkyl bromides. Under PTC conditions, methylation of 3-(4-nitrophenyl)-1,5-diphenylformazan with methyl iodide exclusively gives the corresponding verdazyl radical. 3-Substituted 2,4,6-triphenylverdazyls containing various di(cyclo)alkylamino moieties at the C(3) position of the verdazyl ring are prepared by the reaction of 1,3,5-triphenylformazan with the corresponding 1-[N,N-di(cyclo)alkylaminomethyl]benzotriazoles under the efficient catalysis of barium hydroxide monohydrate. Sonication of this reaction allows the yields of the verdazyls to be substantially increased. A bis-verdazyl N,N-bonded in the C(3) positions was synthesized. All the radicals obtained were characterized by microanalysis, and by UV–visible and ESR spectroscopy.

β-(N,N-Dialkylamino)ethyl arylthiosulfonates 2, new simulants for the hydrolysis and oxidation chemistry of VX (1), are prepared in good yield by reaction of a potassium arylthiosulfonate with a 2-chloroethylamine. Alkaline hydrolysis of 2 results in cleavage of the S-S bond to give sulfinic acids and disulfides. Like VX, oxidation of 2 by N-sulfonyloxaziridine 12 occurs exclusively on nitrogen to give the corresponding amine oxide which subsequently undergoes a Cope elimination reaction affording the vinyl sulfide 14

The syntheses of five new 4-alkyl-2-iodosobenzoic acids (3) are described. The iodine atom was introduced by ortho-directed lithiation of 4-alkylbenzyl alcohols followed by treatment with I 2 . The catalytic effectiveness of each of the products in the hydrolysis of 4-nitrophenyl diphenyl phosphate in microemulsions was studied. The 4-methyl- and 4-ethyl-substituted products were each found to be significantly better catalysts than the standard nonalkylated 2-iodosobenzoic acid (3, R = H). These results would indicate that microemulsions of these materials may find use in detoxification procedures

We have measured the second order rate constants for the uncatalyzed and o-iodosobenzoate catalyzed hydrolysis of p-nitrophenyldiphenyl phosphate in microemulsions containing the surfactant cetyltrimethyl ammonium bromide, the cosurfactants 1-alkyl-2-pyrrolidinones, and the oils hexadecane, toluene, and 4-tert-butyltoluene. Pseudo-ternary phase maps have been prepared for systems containing 1-methyl-2-pyrrolidinone and 1-cyclohexyl-2-pyrrolidinone as cosurfactants. Microemulsions containing N-alkyl-2-pyrrolidinones as cosurfactants effectively penetrate polymers, solubilize phosphate esters, and provide media in which phosphate esters hydrolyze rapidly.

Poly(amidoamine) (PAMAM) dendrimer shell reagents possessing either nucleophilic (i.e., primary amines) or electrophilic (i.e., carboxymethyl esters) functional groups have been covalently assembled around appropriate electrophilic or nucleophilic dendrimer core reagents to produce partial shell filled/core-shell tecto(dendrimers). Partial shell-filled products with saturation levels ranging from 28% to 66% were obtained. These metastable, remarkably monodispersed assemblies possess functionally differentiated nano-cusps and clefts that exhibit “autoreactive” behavior. Pacification of these autoreactive products with appropriate alkanolamine reagents produced robust, nonreactive, “hydroxy-amine-differentiated” surfaces that exhibit very active self-assembly properties. Based on the monodispersity, dimensional scaling, and electrophoretic similarities of PAMAM dendrimers to globular proteins, these assemblies may be viewed as crude biomimetics of classical core shell-type protein aggregates. These dimensionally larger, but analogous PAMAM core-shell tecto(dendrimer) architectures extend and complete a similar pattern of autoreactivity and pacification that was observed earlier for traditional mono PAMAM dendrimer core-shell modules possessing unsaturated shell levels.

Influence d'acides iodosyl-2 et iodyl-2 benzoiques sur la vitesse d'hydrolyse du (diphenyl nitro-4 phenyl) phosphate, de l'(isopropyl O-[nitro-4 phenyl] phenyl) phosphinate, et de l'hexanoate de p-nitrophenyle

Spectre RMN, de 13 C de cryptands [2.1.1], [2.2.1] et [2.2.2] en presence de Li + , Na + , K + , Ca 2+ et Ba 2+ en solution dans D 2 O/MeOH ou CDCl 3 . La relaxation longitudinale presente une augmentation surprenante pour la plupart des metaux alcalins mais pas pour les alcalinoterreux. Interpretation de cette augmentation