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The application of gas chromatography chemical ionization mass spectrometry to the determination of a variety of auryl aikylphosphonates, phosphonofluondates, phosphonothiolates and an amidophosphorocyanidate is described. Comparison is made between the electron ionization and chemical ionization mass spectrometry of these compounds. Chemical ionization mass spectrometry is shown to enhance the capability for identification, espeually when a limited sample is available. Results indicate that methane is highly useful for obtaining protonated molecular ions and assouation ions (formed by the transfer of a reactant ion to a sample molecule) as well as meaningful fragment ions. Ionizing ethylene and isobutane gives protonated molecular ions as base peaks for all of the compounds studied, induding those where a lower abundance of the [MHI' ion is found via methane chemical ionization mass spectrometry. Ethylene is superior to isobutane on the basis of its effectiveness for serving as both a carrier and a reagent gas and gives better sensitivity. Although not an intrinsic part of this present study, analytical sensitivities in the subnanogram range were found.Mass spectrometry has been studied as a means for characterization and identification of a variety of organophosphorus compounds.14 The mass spectrometry of a number of phosphorus pesticides, most of which are alkylphosphates, has been reported by Damico7 among others. With few exceptions,8 reported investigations on organophosphorus compounds have been limited to electron ionization mass spectrometry.For numerous materials the excessive molecular ion fragmentation occurring under EIMS conditions makes positive identification and quantitative analysis quite difficult. Furthermore, this difficulty becomes more pronounced when unknown, gas chromatographic inseparable materials, are present. This is particularly true when examining complex dilute residues or industrial wastes, whether in environments such as air, water, earth, vegetation, or from forensic type substrates. Extracts and sample concentrates can contain biological and other residues which are orders of magnitude more abundant than the nanogram or picogram quantities of unknown or even known material.The investigation reported here on 13 selected alkylphosphonates is actually representative of at least 30 compounds that were studied. The majority of the compounds showed no detectable molecular ion with EIMS. With some of these, considerable difficulty would be experienced in attempting to differentiate or identify structures with certainty due to either excessive fragmentation and interfering background, or the commonality of the predominant ions formed by EIMS.t Author to whom correspondence should be addressed.f Present address: US Army Environmental Hygiene Agency, APG, Maryland 21010, USA Chemical ionization mass spectrometry9-18 appeared to be particularly attractive for obtaining the higher mass ions that we had found lacking using EIMS. An added benefit of CIMS was the potential flexibility in anal...

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to avoid difficulty with nitric acid in the later reduction of vanadium with zinc. Following the reduction with zinc and pH adjustment, the organic extract should have only an amber to slight red coloration. A deep red color indicates incomplete reduction of ferric iron and, therefore, the need of zinc. Although efforts were made to evaporate the organic extracts completely to dryness on a hot plate, the vanadium results were lorn. A literature search indicated that metal acetylacetonates have relatively low boiling points. The evaporation of the final 10 ml. from a water bath eliminated the loss of vanadium as the volatile metal chelate. The analytical results in Table I incorporate the factor 1.07 to compensate for a single extraction a t pH 2.0 (93% extraction from Figure 1). Double extraction or extractions a t higher p H values were avoided to reduce the simultaneous extraction of interfering elements. Aluminum and titanium are partially extracted with vanadium; aluminum does not interfere in the peroxide color procedure for vanadium, but titanium does. Although steel samples rarely contain both titanium and vanadium, the titanium peroxide interference can be destroyed by adding ammonium fluoride. lIolybdenum, an element which ordinarily accompanics vanadium and titanium in a cupferron separation and forms a yellow peroxy complex, is not extracted by acetylacetone from a reduced solution. The method should find utility in the analysis of steels containing low amounts of vanadium which are not suitable for potentiometric titration or to high vanadium steels when the available sample is limited.)Two methods are presented for the colorimetric estimation of tertiary aliphatic amines using, in the one case, the reaction of amine with aconitic anhydride and, in the other, the reaction o f amine with chloranil. When used in conjunction with one another, the methods can be used for quantitatively differentiating between tertiary amines and amine salts or quaternary amines. The respective sensitivities for tertiary aliphatic amines are on the order o f 3 y per ml. of solution for aconitic anhydride and 50 y per ml. for chloranil. ETHODS were required for the M estimation of and differentiation between small quantities of aliphatic tertiary amines, their amine salts, and quaternary amines a t a time when very little information was available on either micro or macroprocedures. The problem was one of determining the quantity of free aliphatic tertiary amines and amine salts in mixtures containing them in small amounts, Palumbo (3) found that cis-aconitic anhydride could be used for detecting tertiary aliphatic amines in the presence of primary and secondary amines. This qualitative procedure was adapted by Cromwell (f) to the quantitative colorimetric determination of trimethyl-Present address, Johns Hopkins University, Baltimore, Md. amine. Richter and associates (4)and Dyer (2) estimated trimethylamine from aqueous solution as a yellow picrate formed in picric acid-toluene solution. Sivadjian ( 5 ) found that chlo-ra...

A method for the quantitative estimation of 1-naphthol which depends on the formation of a blue color when the compound reacts with sodium cupribromide. No interference is encountered when 2-naphthol and other phenolics are present.