Protonated amine cations

Protonation of an amine gives an amine salt. The amine salt is composed of two types of ions the protonated amine cation (an ammonium ion) and the anion derived from the Salts OT Am IFI6S acid. Simple amine salts are named as the substituted ammonium salts. Salts of complex amines use the names of the amine and the acid that make up the salt. 

Gradient elution is feasible with modem suppressed conductivity detection. Several aliphatic amines were separated as the protonated amine cations in Fig. 7.3 using a sulfuric acid gradient [5]. The increasing acidity served to reduce the effective exchange capacity of the ion exchanger and thereby speed up elution of the larger monoamines and the diamines. 

As in anion chromatography, the IC separation of organic cations has long been known, or at least suspected, that its mechanism involved more than simple ion exchange. Hoffman and co-workers [9,10] have shown that two mechanisms occur in such cases ion exchange and hydrophobic interaction between the sample cations and the resin matrix. For example, these authors showed that the slopes of the linear plot of log k vs. carbon number for protonated amine cations decrease going from 30 % acetonitrile (70 % water) to 70 % acetonitrile in the eluent. This is due to lower hydro-phobic interaction in the 70 % acetonitrile. 

After trying several different inorganic acids, methanesulfonic acid was selected as the eluting acid for the separation of protonated amine cations. In IC of cations with as the eluting cation, k should vary according to the following equation ... 

Jones et al. obtained exeellent separation of 15 alkali, alkaline earth, and divalent transition metal ions with 6.5 mM HIBA at pH 4.4 to partially complex some of the cations [11]. A protonated amine cation containing a benzene ring (Waters UV Cat 1) was used for indirect UV detection. All of the 13 lanthanides have been separated using HIBA under similar conditions (Fig. 10.12). 

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

Sample ions that absorb sufficiently in the UV or visible spectral region may be detected by direct spectrophotometry. Indirect spectrophotometric detection is commonly used for ions that do not absorb. An absorptive reagent is added to the BGE, and this gives a peak in the direction of reduced absorbance when a sample ion passes through the detector. The absorbing reagent, which is sometimes called a visualization reagent, should have a mobility that matches those of the sample ions as closely as possible. Chromate is often used for the indirect detection of anions and a protonated amine cation, such as benzylamine, for detection of cations. 

Carboxylates with weakly basic cationics. As for quats. Results of acid-base titration must be interpreted bearing in mind the degree of protonation or deprotonation in the product acid titration measures free bases plus carboxylate anions, titration with alkali measures free acids plus protonated amine cations. If only weak acids and bases are present, acid titration measures the bases and alkali titration the acids. 

Protonated amine cations or ammoniums (AH "" ") are perhaps the most popular and widely employed cationic templates or components for many chemical... 

In contradistinction to this, weak ferromagnetism has been observed in a number of chloro and bromo complexes of the type M2[CrX4] (M = a variety of protonated amines and alkali metal cations, X = Cl, Br), which are analogous to previously known copper(II) complexes (p. 1192). They have magnetic moments at room temperature in the region of 6BM (compared... 

Many years ago, L. F. Audrieth studied numerous reactions of amine hydrochloride salts. These compounds contain a cation that is a protonated amine that can function as a proton donor. Consequently, the molten salts are acidic and they undergo many reactions in which they function as acids. This behavior is also characteristic of ammonium chloride as well as pyridine hydrochloride (or pyridinium... 

Surfactants that form micelles have also been shown to accelerate the formation of nitrosamlnes from amines and nitrite (33.) A rate enhancement of up to 80 0-fold was observed for the nitrosation of dihexylamine by nitrite in the presence of the cationic surfactant decyltrimethylammonium bromide (DTAB) at pH 3.5. A critical micelle concentration (CMC) of 0.08% of DTAB was required to cause this effect, which was attributed to a micelle with the hydrocarbon chains buried in the interior of the micelle. The positively-charged ends of the micelle would then cause an aggregation of free nitrosatable amine relative to protonated amine and thus lead to rate enhancements. Since surfactants are commonly used in water-based fluids (25-50% lubricating agent or 10-2 0% emulsifier in concentrates), concentrations above the CMC of a micelle-forming surfactant could enhance the formation of nitrosamines. 

The complexation of protonated amines, RNHJ, by crown ethers differs in many aspects from the complexation of metal cations. Whereas complexes with metal cations derive their binding energy mainly from electrostatic forces, complexes with ammonium ions are likely also to be stabilized by hydrogen... 

The chemistry of ionized, protonated and cationated amines in the gas phase... 

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