Arsenates, alkyl

Biomethylation may also produce more complex alkyl arsenic groups. As(C2H5)(CH3)2 has been found in landfill and sewage gas, and probably also exists in natural gas (Bentley and Chasteen, 2002), 251. As(C2H5)3 may also occur in landfill gases and probably natural gas (Bentley and Chasteen, 2002), 251. Further details on the reduction and methylation biochemistry of arsenic are discussed in Chapter 4. 

Alkyl arsenic compounds - Electron capture or flame ionisation Use of sodium borohydride as reducing agent prior to GLC 0.21 pg L [683, 704- 720]... 

The gas chromatography-microwave plasma detector (GC-MPD) technique has been applid to the analysis of alkyl arsenic acids in environmental samples . 

The method has been useful for the preparation of alkyl and aryl derivatives, and some unsymmetrical compounds as shown in equations 72 , 73 ° , 74 ° and 75 °°. In the reaction of unsymmetrically substituted compounds such as 3, cleavage of the alkyl-arsenic bond is preferred to that of the aryl-arsenic bond (equation 75 °°). The ease of thermolysis of R3ASX2 decreases in the order X = I > Br > Cl > F, R = alkyl > aryl. 

Metabolism of Alkyl Arsenic and Antimony Compounds Marie Vahter and Emiinio Marafante... 

The simple alkyl arsenicals which have been investigated are (CH3)2AsCN (400), CH3ASI2 (407), and [(CH3)2As]2S2 (402). The structure of the cyanide... 

Concentrations up to 2000 mg/kg were found in soils close to metallurgical foundries. Soils contaminated with pesticides may contain up to 290-625 mg/kg. Aerated soil layers at the surface contain As(V), whereas industrial pollution or agricultural pesticides are composed mainly of As(III). Arsenate ions are fixed by many soil components, especially hydrated Fe and A1 oxides. The transfer of arsenic from soil to plants is low, i.e., 0.1-0.5 mg/m. The kind of plant may have an influence (see Sec. 2.1.4) but there is no more detailed information. Several strains of bacteria in the environment accelerate the oxidation of As(III) to As(V) or methylate and alkylate arsenic mainly to DMAA which is partially released to the atmosphere. High contaminations of As(III) destroy these microorganisms [4,8,12,18-21,26]. 

My early research was orthodox organic chemistry and my first entrance into the polymer field was accidental in connection with a reaction between tri-ethyl n-butyl arsonium bromide and lithium ethyl which we ran, hoping to obtain a penta alkyl arsine which had once been tentatively reported by Cahours, We did not obtain a penta alkyl arsenic derivative but a gas was liberated which proved to be very pure ethane. There is no good way to account for ethane to be produced without an equal amount of ethylene being formed. So we postulated that the excess lithiiim ethyl had caused the ethylene to polymerize. We showed this to be possible by treating a solution of lithium ethyl in a hydrocarbon solvent with ethylene. The ethylene disappeared rather rapidly and a white polymeric solid separated which was apparently linear polyethylene. At that time, polyethylene was not considered to be very important so no further work on this polymerization was carried out. ... 

Alkyl arsenic — Electron capture or Use of sodium borohydride as 0.2lMgL [683,... 

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