Quaternary amines acid value

D 2076-64 (Reapproved 1987) Acid Value and Amine Value of Fatty Quaternary Ammonium Chlorides D 2078-86 Iodine Value of Fatty Quaternary Ammonium Chlorides D 2080-64 Average Molecular Weight of Fatty Quaternary Ammonium Chlorides... 

American Society for Testing and Materials, Acid value and amine value of fatty quaternary ammonium chlorides, D2076-92. West Conshohocken, PA 19428. 

Reaction selectivity of the parent ortho-QM has also been explored with a variety of amino acid and related species.30 In these examples, the rates of alkylation and adduct yields were quantified over a range of temperatures and pH values. The initial QM3 was generated by exposing a quaternary benzyl amine (QMP3) to heat or ultraviolet radiation (Scheme 9.10). Reversible generation of QM3 was implied by subsequent exchange of nucleophiles at the benzylic position under alternative photochemical or thermal activation.30 Report of this work also included the first suggestion that the reversible nature of QM alkylation could be used for controlled delivery of a potent electrophile. 

An anionic surfactant is soluble only at a pH greater than tf pqf its ionizable group, whereas a cationic surfactant (e.g., primary, secondary, ortertiary amines) is soluble only at a pH less than its pKg. However, quaternary ammonium surfactants remain soluble at all pH values. Zwitterionic surfactants, for example, sulfobetaine surfactants, are neutral from pH 2 to 12, whereas some nonionic surfactants, for example, alkyldimethylamine oxides, are converted to cationic surfactants by protonation at acidic pH. 

Cinchona alkaloids, of course, have occupied the central position in the design of chiral PTCs. By employing a simple chemical transformation of the tertiary amine ofthe natural cinchona alkaloids to the corresponding quaternary ammonium salts, using active halides (e.g., aryl-methyl halides), a basic series of PTCs can be readily prepared. Cinchona alkaloid-derived PTCs have proved their real value in many types of catalytic asymmetric synthesis, including a-alkylation of modified a-amino acids for the synthesis of higher-ordered a-amino acids [2], a-alkylation of... 

The drug is not destroyed by cooking, but the Indians can eat the hunted animal because tubocurarine is not able to cross the gut membrane by passive diffusion and therefore is not absorbed and does not accumulate in the bloodstream. This is because the drug is both a quaternary ammonium compound, ionised at all values of pH, and a tertiary amine which will exist predominately as the cation at gut pH. The drug is also a phenol, but phenols are normally too weakly acidic to ionise at the range of pH values found in the body. 

Many alkaloids are difficult to crystallize as free base, but do crystallize as a salt. Most alkaloids have basic properties. The pK values vary from 6 to 12, with most alkaloids in the range of 7-9. In general the free base is soluble in organic solvents and not in water. Protonation of the amine function under acidic conditions usually results in a water-soluble compound. This characteristic is widely used in the selective isolation of alkaloids. Quaternary alkaloids are poorly soluble in organic solvents but are soluble in water at any pH. 

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