Ammonium acetates, quaternary

Pashley R M, McGuiggan P M, Ninham B W, Brady J and Evans D F 1986 Direct measurements of surface forces between bilayers of double-chained quaternary ammonium acetate and bromide surfactants J. Phys. Chem. 90 1637-42... 

The quaternary ammonium compounds paraquat and diquat are widely used non-selective contact herbicides, which are extremely toxic to humans. Fee et al. [112] established an HPLC-MS-MS procedure for the determination of these herbicides in whole blood and urine using ethyl paraquat as internal standard. After extraction with Sep-Pak C18 cartridges, analytes were separated using ion pair chromatography with heptafluorobutyric acid in 20 mM ammonium acetate and acetonitrile gradient elution. Detection was carried out in ESI MS-MS SRM mode. Using similar separation and detection conditions, paraquat, diquat, difenzoquat, and a number of structurally related quaternary nitrogen muscle relaxants (see Section 20.2.1.3) were determined in whole blood by Ariffin and Anderson [113]. 

From this ranking, quaternary ammonium acetates, chlorides, nitrates, and bromides are apparently more soluble in organic solvents such as aqueous /-butyl alcohol than are the corresponding quaternary ammonium hydroxides. Thus these quaternary ammonium salts would be readily extracted into the organic phase. In addition, a high concentration of... 

The total synthesis of spirotryprostatin B was accomplished by K. Fuji et al using an asymmetric nitroolefination to establish the quaternary stereocenter." The conversion of the nitroolefin to the corresponding aldehyde was carried out under reductive conditions using excess titanium(lll) chloride in aqueous solution. The initially formed aldehyde oxime was hydrolyzed in situ by the excess ammonium acetate. 

Recently Wilson and Joule 158> studied the demethylation of a variety of quaternary ammonium acetates in aprotic solvents. Earlier Lawson and Collie 92> showed that the decomposition of solid tetramethylammonium acetate at 180—200 °C gives the methyl ester in good yield. However, the use of an aprotic solvent significantly lowers the temperature (60—140 °C) required for decomposition. This reaction is most useful for the demethylation of aromatic quaternary ammonium salts that are soluble in benzene or benzene-chloroform mixtures. Its application to aliphatic quaternary ammonium salts requires a longer time, although N,N-dimethylpiperidinium acetate was demethylated at 100 °C in xylene-... 

Melville and Goddard [204] used rotating disk flow to measure the mass transfer coefficient between the solid and liquid phases in SLPTC for the reaction of benzyl chloride and solid potassium acetate using Aliquat 336 as the catalyst in acetonitrile as solvent. The concentration of quaternary ammonium acetate is expressed in the following equations ... 

Acid-catalysed esterification reactions in ILs have been extensively studied, and will be the main focus of this section. In 2001, Deng et al. first reported the synthesis of allq l acetate esters in an IL with concentrated sulfuric acid as the acid catalyst (Scheme 3.7). The majority of subsequent studies, however, have switched away from an IL with an added acid catalyst and towards Bronsted acid ionic liquids (BAILs) - a type of task-specific ionic liquid. BAILS incorporate an acidic moiety (typically either a sulfonic acid or a protonated nitrogen) on the cation allowing the BAILS to have dual functionality as both a solvent and a catalyst. There are several different classes of BAILs that have been applied to esterifications such as imidazo-lium 1, imidazolium sulfonic 2, phosphonium sulfonic 3, pyridinium sulfonic 4, quaternary ammonium 5, quaternary ammonium sulfonic 6 and lactam 7 based-BAILs (Scheme 3.8). 

Figure 6.84 Separation of quaternary ammonium compounds on Acclaim Mixed-Mode WCX-1, 5(im. Column dimensions 150 mm X4.6mm i.d. column temperature SOT eluent MeCN/ammonium acetate, pH 5.2...

As shown, both alkyl halides and Mannich base quaternary salts have been used as alkylating reagents. With j -nitrobenzaldehyde and ammonium acetate in acetic acid a Mannich reaction occurs, the intermediate (37) so produced reacting further to give a pyrimidine ... 

From ehloromethyl or bromomethyl aromatic compounds by heating with hexamethylenetetramine (hexamine) in aqueous alcohol or aqueous acetic acid. A quaternary ammonium compound is formed, which yields the aldehyde upon treatment with water in the presence of hexamine for example... 

Carbonyl Compounds. Cychc ketals and acetals (dioxolanes) are produced from reaction of propylene oxide with ketones and aldehydes, respectively. Suitable catalysts iaclude stannic chloride, quaternary ammonium salts, glycol sulphites, and molybdenum acetyl acetonate or naphthenate (89—91). Lactones come from Ph4Sbl-cataly2ed reaction with ketenes (92). 

Nitrile Intermediates. Most quaternary ammonium compounds are produced from fatty nitriles (qv), which are ia turn made from a natural fat or oil-derived fatty acid and ammonia (qv) (Fig. 2) (see Fats AND FATTY oils) (225). The nitriles are then reduced to the amines. A variety of reduciag agents maybe used (226). Catalytic hydrogenation over a metal catalyst is the method most often used on a commercial scale (227). Formation of secondary and tertiary amine side-products can be hindered by the addition of acetic anhydride (228) or excess ammonia (229). In some cases secondary amines are the desired products. 

Physical Properties. Sulfuryl chloride [7791-25-5] SO2CI2, is a colorless to light yellow Hquid with a pungent odor. Physical and thermodynamic properties are Hsted ia Table 7. Sulfuryl chloride dissolves sulfur dioxide, bromine, iodine, and ferric chloride. Various quaternary alkyl ammonium salts dissolve ia sulfuryl chloride to produce highly conductive solutions. Sulfuryl chloride is miscible with acetic acid and ether but not with hexane (193,194). 

---