Alkyltrimethylammonium salts

Smaller, hard cations, such as alkyltrimethylammonium salts and crown ether-cation complexes, will promote the elimination of dichlorocarbene to form a hard ion pair of type Q+C1 . 

Several alkyltrimethylammonium salts were also examined in this study 53b The predominant reaction is reductive cleavage to give the alkane and tertiary amine. In the discussion of the mechanism of the reaction, it was suggested 53> that methyl and other primary alkyl groups cleave from nitrogen as carbanions while secondary and tertiary alkyl groups cleave as free radicals (see Sect. VI. C. for further discussion of radical cleavage reactions). 

In the early 1990 s Kuroda et al. reported preparation of porous materials resulting from interaction of layered silica kanemite with alkyltrimethylammonium salt solutions [21]. Later on [22] they proposed the mechanism labeled FSM (Folding Sheet Mechanism see Fig. 4) to rationalize the nature of the products [23,24],... 

Alkyltrimethylammonium salts (cetyl trimethylammonium bromide, cetyl trimethylammonium chloride), cetylpyridinium chloride, benzalkonium chloride, benzethonium chloride, 5-bromo-5-nitro-l,3-dioxane, dimethyldioctadecylammonium chloride, cetrimonium bromide, dioctadecyldimethylammonium bromide... 

The cationic agents are long-chain cations, such as amine salts and quaternary ammonium salts. The amine salts are susceptible to hydrolysis so they are not frequently used. Derivatives of alkyltrimethylammonium salts and alkylpyridium salts are the most common in this group. 

Fig. 7.3 Cross-reactivity of NMBD-reactive IgE antibodies with quaternary ammonium compounds. Inhibition by tetraalkylammonium and alkyltrimethylammonium salts of the binding of alcuronium-reactive IgE antibodies to an alcuronium-solid phase conjugate. The serum was from a patient who experienced anaphylaxis to alcuronium and is the same serum used in experiments summarized in Figs 7.1 and 7.2. Key alcuronium plus sign) tetrameth-ylammonium bromide (open circle), tetrapropylammo-nium bromide filled square) , tetrapentylammonium...

Fig. 5. The X-ray diffraction patterns and corresponding benzene isotherms for MCM-41 materials formed from alkyltrimethylammonium salts having alkyl chain lengths of n= 12,14, and 16...

Cationic surfactant a surfactant in which the hydrophilic part carries a positive charge. Examples alkyltrimethylammonium salts, RN (CH3)3, alkyldimethylbenzylammonium salts, RN" (CH3)2CH2C6H5. For typical anions see section 2.2.3. 

Betaine esters (Fig. 16) have been suggested as potential alternatives to alkyltrimethylammonium salts. They have been reported to be stable in slightly addic formulations and to degrade in sewage into betaine and fatty alcohol [144-147]. 

The a ,P-mode is a p-elimination unleashed by an electron-rich carbon center that is intramolecularly located at an a -position. Such a process is frequently met with ylides. It is related to the Cope elimination of amine oxides, which also implies a syn-periplanar scission but occurs at much higher temperatures. Organolithiums deprotonate an alkyltrimethylammonium salt preferentially or exclusively at a methyl group. Subsequently, the electron-rich carbon in the ylide 243 acts as a base and accomplishes an... 

C o dialkyldimethylammonium and Ci2 alkyltrimethylammonium salts from beer and water... 

The use of an internal standard, a deuterated analog of the particular compound determined, allows the quantitative application of FAB to environmental analysis. This has an advantage over other instrumental techniques in that very little sample work-up is necessary and is suitable for quantitative analysis below the 10 ppb range (109). Deuterated standards of alkyltrimethylammonium salts can be prepared relatively easily by reaction of perdeuterated trimethylamine with the corresponding alkyl bromide (110). 

The ISO method for determination of cationics gives separate procedures for determination of high and low molecular weight compounds (94,95). Low MW compounds (MW less than about 500) such as alkyltrimethylammonium salts are simply dissolved and titrated as described above. Higher MW compounds, such as dialkyldimethylammonium fabric softeners have poor water solubility and are therefore taken up in isopropanol, diluted with water, and used to titrate a known quantity of anionic surfactant,... 

C12-C16 alkyltrimethylammonium salts assay Polymer Laboratories PLRP-S poly(styrene/divinylbenzene), 4.7 X 250 mm 60 38 2 CH3CN/H2O/HOAC,0.005 M in sodium p-xylenesulfonate Inverse photometric detection, 262 nm 181 ... 

Nishiyama, N. Toshima, Y. Ikeda, Y. (1995). Biodegradation of alkyltrimethylammonium salts in activated sludge. Chemosphere, 30, 593-603, ISSN 0045-6535,... 

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