Amine alkylammonium salt

Amines react with strong acids to form amine salts. The pKas of amine salts are related to the base strength of the corresponding amines. Alkylammonium salts have pKas of 9-10 while arylammonium salts have pKas of 4-5. The fact that these salts are usually water-soluble can be exploited in separating amines from neutral or acidic contaminants. Chiral amines can be used to resolve enantiomeric acids, through the formation of diastereomeric salts. 

The derivative-forming process in pyrolytic alkylation involves two sequential reactions deprotonation of the acidic substrate in aqueous solution by the strongly basic tetra-alkylammonium ion and the thermal decomposition of the quaternary M-alkylammonium salt formed to give a tertiary amine and alkyl derivative. For some weak acids both processes may occur virtually simultaneously in the injector oven of the gas chromatograph. 

Similarly, reactive oxide mixtures are also used to synthesize aluminophosphate molecular sieves, usually starting from phosphoric acid along with the addition of alumina and silica sources analogous to those used in zeolite synthesis with a notable exception alkylammonium salts and amines were ultilized in structure-direchng and space filling to the exclusion of alkali hydroxide solutions and alkali metal salts. 

Carbon disulphide reacts additively with primary and secondary aliphatic amines to form alkylammonium salts of alkyldithiocarbamic acids. The products obtained with dimethylamine, diethylamine and piperidine, also certain derivatives of these products, are manufactured on a large scale for use as accelerators in the vulcanisation of rubber. With aromatic amines the disulphide reacts with elimination of hydrogen sulphide and formation of substituted thio-ureas, e.g. thiocarbanilide. 

In our attempts to synthesize nano structured or even nanoporous chromium (III) oxide we used a great variety of surfactants (amines, polyethylen oxides, carboxylates, sulfates, phosphates and quartemary alkylammonium salts) and Cr3+ precursors (nitrate, acetate, acetylacetonate and iso-propyl ate) to obtain the desired materials [19]. Different kinds of interaction are established throughout the structure-directing process such as electrostatic (S+... 

Absorption of ultrasound waves 121-4. 122-4 Acceptor number (.AN) 160 Acetylator 203 Acidic properties 167-72 Acidity 165-73 Activation energy 222 Activation entropy 57 Activation volume 58 Adiabatic isentropic compressibility KL Alkylammonium salts 223 Alkylator 203 Aminator 203 Antifreeze 203 Antoine equation 82, 83 Applications 203-34 survey 203-10. 204-9 see also specific applications Aquamolality 42 Aqueous solubility 174-86 Autoignition temperature 26-30, 32 Autoprotolysis constant 167-72. 173. 215... 

Even this is not all If the alkylation were to continue, the secondary and the tertiary amines would be produced all together in the reaction mixture. The reaction comes to an end only when the tetra-alkylammonium salt R4N+ is formed. This salt could be the product if a large excess of alkyl halide R1 is used, but other more controlled methods are needed for the synthesis of primary, secondary, and tertiary amines. 

Alkenes may be obtained by elimination reactions from alkyl haUdes, alcohols, sulfonates or amines. The substitution pattern of the alkene and the stereospecificity of these methods depend quite subtly on the structure of the individual substrate. If the leaving group occupies an unsymmetrical position in a compound, one of two isomeric alkenes can be formed (Scheme 3.1). Elimination to give an alkene bearing the greatest number of alkyl groups is known as the Saytzeff elimination and is commonly found with alkyl halides. When the elimination gives preferentially the less-substituted alkene, it is known as the Hofmann elimination This substitution pattern is commonly foimd with the elimination of alkylammonium salts. In practice, mixtures of alkenes are often obtained. 

An analogous reaction can be effected for primary amine products. The similarities in the infrared spectra of the anions in the sodium and alkylammonium salts support the structures proposed for these products. The stabilities and properties of the products obtained from various amines have been described (12). When hindered amines are employed, no product is obtained, presumably because of a steric effect. By analogy with the structure of S03N202 , the following structure is proposed for the anion. 

Included in this category are the high-molecular weight primary amines (Primene JMT) secondary amines (Amberhte LA-2) tertiary amines (TOA, TNOA, Alamine 336) and quaternary alkylammonium salts (Aliquat 336). 

The ability of crown polyethers to form complexes with ammonium and alkylammonium salts") gave rise to the development of Cram s concept of host-guest chemistry57). Asymmetric macrocyclic polyethers (host molecules) were designed and synthesized that distinguish between the enantiomers of chiral amine salts (guest molecules). For example, the (R,Reform of polyether (Fig. 66) which was obtained in pure state, forms complexes of different... 

Because amines are bases, they react with acids to form alkylammonium salts. 

Alkylammonium salts are named by replacing the suffix -amine with ammonium. This is then followed by the name of the anion. The salts are ionic and hence are quite soluble in water. 

A variety of important drugs are amines. They are usually administered as alkylammonium salts because the salts are much more soluble in aqueous solutions and in body fluids. 

Alkylammonium salts can neutralize hydroxide ions. In this reaction, water is formed and the protonated amine cation is converted into an amine. 

Thus, by adding a strong acid to a water-insoluble amine, a water soluble alkylammonium salt can be formed. The salt can just as easily be converted back to an amine by the addition of a strong base. The ability to manipulate the solubility of physiologically active amines through interconversion of the amine and its corresponding salt is extremely important in the development, manufacture, and administration of many important drugs. 

How would you quickly convert an alkylammonium salt into a water-insoluble amine Explain the rationale for your answer. 

The reaction of the hexachlorozirconate anion as an alkylammonium salt (RH)2ZrClfl, where R = C2H5NH2, (CH3)2NH, (C.Hsl.NH, (CHsljN, and (C2H5)3N, with excess of amine (152), results in no product with tertiary amines, and very slow solvolysis with secondary amines. A product with a Zr N ratio of 1 2.49 with diethylamine was obtained after 8 weeks, and a product with a Zr N ratio of 1 2.86 with dimethyl-... 

The Paal-Knorr synthesis, in which 1,4-dicarbonyl compounds are treated with NH3 or primary amines (or with ammonium or alkylammonium salts) in ethanol or acetic acid, leads to 2,5-disubstituted pyrroles, and is universally applicable. For instance, hexane-2,5-dione 8 reacts with NH3 to yield 2,5-dimethylpyrrole 9 ... 

P-33 - Efficient co-templating roles of amines and amides admixed with alkylammonium salts for the stabilisation of new AlP04-n topologies... 

The mechanism is almost the same with nucleophiles like ammonia or amines with the only difference that a salt is formed and an extra step is needed to gain the free amine. For example, consider the reaction between ammonia and 1-iodopropane (Fig. G). Ammonia s nitrogen atom is the nucleophilic centre for this reaction and uses its lone pair of electrons to form a bond to the alkyl halide. Due to this, the nitrogen will effectively lose an electron and will gain a positive charge. The C-I bond is broken and an iodide ion is formed as a leaving group, which then acts as a counterion to the alkylammonium salt. 

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