showed good second-order rate constants for the expression, -d(RDX)/dt = &2(OH")(RDX) = MRDX), where ki is the first-order rate constant with excess hydroxide ion. At 25.0 °C the kinetic isotope effect for k2-(RDX-h6)//e2'(RDX-d6) = 2.4. Mass spectral evidence for two short-lived intermediates, pentaproteo (I-h6) and pentadeuterio (I-ds) l,3,5-triaza-3,5-dinitrocyclohexene-l, obtained by loss of the elements of nitrous acid from RDX-h6 and RDX-dg is presented. Products obtained on further hydrolysis of I-h5 include, N02~, N20, NH3, N2, CH20, and HCOO", the relative amounts of which depend on the hydroxide ion concentration. A novel method is presented for generating these base sensitive, short-lived intermediates with strongly basic ion-exchange resins.

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Three pseudomonas-like organisms have been shown to metabolically oxidize 2,4,6-trinitrotoluene (TNT). Capability for this oxidative dissimilation varied with each organism. Of the three, isolate "Y" was the most proficient, isolate "I" was less, and isolate "II" was the least. For accelerated TNT degradation, addition of glucose or a nitrogenous substance was essential. Complete dissimilation within 24 h by isolate "Y" cultures supplemented with 0.5% yeast extract is presumed since no TNT was detectable.

The isomerization reaction of methyl linoleate and methyl linolenate with potassium t-butoxide has been investigated. The compositions of the reaction products formed at three temperatures have been determined and the relationships between these analyses and observed differences in absorptivities by UV spectrometry are discussed. Conclusions concerning the reaction mechanisms are based on compositional analysis and results of experiments using radioactive or stable isotope labeled reagent. Double bonds in molecules which are not conjugated during the reaction retain the original cis configuration. The double bond in the A12 position is the most susceptible to positional isomerization to form the conjugated system. With the diene, this selectivity is small, while with the triene, the shifting of the A 12 bond is the preponderant initial reaction. Isotopic experiments yielded direct evidence for the postulated carbanion mechanism of reaction. An activated methylene group is generally required for the formation of the carbanion. While the UV spectra of the reaction products formed from methyl linolenate at 140 C showed no peak in the diene region, 34% conjugated diene-triene was present. The intact conjugated systems can migrate when the reaction is sufficiently energentic to produce conjugated trienes with double bonds other than the 10, 12, 14 system. The conjugation of triene is a stepwise reaction through the conjugated dienetriene.

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