Quaternary ammonium chlorides

A variety of chemical products and fabrics are reputed to be antibacterial and to prevent odors and the spread of infection (170). One such finish is based on an organosiUcon quaternary ammonium chloride compound (171). Chemical finishing of cotton has also been directed toward improving soil release (172,173), antistatic treatments (174), and rot resistance (175,176). 

Cationic, anionic, and amphoteric surfactants derive thek water solubiUty from thek ionic charge, whereas the nonionic hydrophile derives its water solubihty from highly polar terminal hydroxyl groups. Cationic surfactants perform well in polar substrates like styrenics and polyurethane. Examples of cationic surfactants ate quaternary ammonium chlorides, quaternary ammonium methosulfates, and quaternary ammonium nitrates (see QuARTERNARY AMMONIUM compounds). Anionic surfactants work well in PVC and styrenics. Examples of anionic surfactants ate fatty phosphate esters and alkyl sulfonates. 

Reactions of the Side Chain. Benzyl chloride is hydrolyzed slowly by boiling water and more rapidly at elevated temperature and pressure in the presence of alkaHes (11). Reaction with aqueous sodium cyanide, preferably in the presence of a quaternary ammonium chloride, produces phenylacetonitrile [140-29-4] in high yield (12). The presence of a lower molecular-weight alcohol gives faster rates and higher yields. In the presence of suitable catalysts benzyl chloride reacts with carbon monoxide to produce phenylacetic acid [103-82-2] (13—15). With different catalyst systems in the presence of calcium hydroxide, double carbonylation to phenylpymvic acid [156-06-9] occurs (16). Benzyl esters are formed by heating benzyl chloride with the sodium salts of acids benzyl ethers by reaction with sodium alkoxides. The ease of ether formation is improved by the use of phase-transfer catalysts (17) (see Catalysis, phase-thansfer). 

In order to imderstand the effects of the cation structure in the transesterification between methanol and EC, quaternary ammonium chloride catalysts of different alkyl cations such as TPAC, TBAC, THAC, TOAC, and TDodAC were used at 140 C. Table 1 shows EC conversions after 1 h... 

Tetrachloro derivative 287b was also prepared in 60% yield from cyanogen and oxalyl chloride by prolonged heating in the presence of a catalytic amount of hydrochloric acid and quaternary ammonium chloride (Scheme 70) [88AG(E)1372],... 

Method C The quaternary ammonium chloride (23 mmol) in MeOH (40 ml) is shaken with solid KF (2.2 g) for ca. 15 min at room temperature. The mixture is filtered and a further amount of KF (2.2 g) is added and the mixture is shaken for a further 15 min. The MeOH is reduced to 75% of its volume and filtered to remove KCI. The evaporation and filtration processes are repeated three times to yield the hygroscopic ammonium fluoride (>95% containing ca. 5-10% ammonium chloride). 

The synthesis of polyhalide salts, R4NX , used in electrophilic substitution reactions, are described in Chapter 2 and H-bonded complexed salts with the free acid, R4NHX2, which are used for example in acid-catalysed cleavage reactions and in electrophilic addition reactions with alkenes, are often produced in situ [33], although the fluorides are obtained by modification of method I.I.I.B. [19, 34], The in situ formation of such salts can inhibit normal nucleophilic reactions [35, 36]. Quaternary ammonium chlorometallates have been synthesized from quaternary ammonium chlorides and transition metal chlorides, such as IrClj and PtCl4, and are highly efficient catalysts for phase-transfer reactions and for metal complex promoted reactions [37]. 

Arenediazonium salts react with quaternary ammonium chlorides to yield chloroarenes in low yield (50%) [9]. 

We tried a different approach to create a supported chloroaluminate IL on silica to be used for the toluene carbonylation reaction. A functionalized silica (2-(2-pyridyl)ethyl-functionalized silica gel (Sigma Aldrich 53,798-5) was reacted with one equivalent of n-propyl chloride in toluene (0.2 M) for 12 h at 140 °C to form the quaternary ammonium chloride." The pyridyl concentration on the silica was 1.3 mmol/g silica per the vendor. Prior to reaction with the -propyl chloride, the solid was evacuated at 150 °C for 1 h. The supernatant liquid was decanted, then the solid was evacuated at room temperature overnight. A small portion of this solid was examined by C-MAS-NMR to determine how well the quaternization reaction had occurred. The spectra of the sample before and after treatment with the -propyl chloride were compared to show the same peaks in both samples 1.42, 12.22, 29.87, 47.81, 110.5, 120.8, 134.9, 147.4, and 163.5 ppm however, the treated sample showed the peak at 110.5 ppm grew after the treatment confirming the success of the quaternization reaction. This... 

The combination of quaternary ammonium chloride salt, such as l-ethyl-3-methylimidazolium chloride (EMIC), with... 

One type of room-temperature ionic liquid is the mixture of A1C13 and a quaternary ammonium chloride (R+C1 ) like l-ethyl-3-methylimidazolium chloride (EMI+C1 ) and 1-butylpyridinium chloride (BP+Ch) [28]. At 1 1 molar ratio of A1C13 and R+C1 , A1C13 exists as AICI4 but the AICI4 ions slightly dissociate into AI2CI7 and Cl-. 

Dichlorocarbene is the reactive intermediate formed by the reaction of alkali on chloroform, and typically it adds to olefins to give 1,1-dichlorocyclo-propanes. The PTC procedure for the generation of dichlorocarbene is particularly useful and is illustrated by its reaction with cyclohexene to form (38) (Expt 7.15). The mechanism is formulated below and probably involves the reaction of the quaternary ammonium hydroxide with chloroform at the phase boundary, and dissolution into the organic phase of the quaternary ammonium derivative of the trichloromethyl anion (41). This species breaks down to form dichlorocarbene and the quaternary ammonium chloride. The latter returns to the aqueous phase to maintain the cycle of events, while the dichlorocarbene reacts rapidly with the cyclohexene in the organic phase. 

The group of Arai and Nishida investigated the catalytic asymmetric aldol reaction between tert-butyl diazoacetate and various aldehydes under phase-transfer conditions with chiral quaternary ammonium chloride 4c as a catalyst. The reactions were found to proceed smoothly in toluene, even at —40°C, when using 50% RbOH aqueous solution as a base, giving rise to the desired aldol adducts 23 with good enantioselectivities. The resulting 23 can be stereoselectively transformed into the corresponding syn- or anti-P-hydroxy-a-amino acid derivatives (Scheme 2.20) [42],... 

Isquith AJ, Abbott EA, Walters PA (1972) Surface-bonded antimicrobial activity of an organosilicon quaternary ammonium chloride. Appl Microbiol 24 859-863... 

Until recently, the most popular reference half-cell for potentiometric titrations, polarography, and even kinetic studies has been the saturated aqueous calomel electrode (SCE), connected by means of a nonaqueous salt bridge (e.g., Et4NC104) to the electrolyte under study. The choice of this particular bridge electrolyte in conjunction with the SCE is not a good one because potassium perchlorate and potassium chloride have a limited solubility in many aprotic solvents. The junction is readily clogged, which leads to erratic junction potentials. For these practical reasons, a calomel or silver-silver chloride reference electrode with an aqueous lithium chloride or quaternary ammonium chloride fill solution is preferable if an aqueous electrode is used. 

Finally, Kohl et al. used quaternary ammonium chlorides, e.g. benzyltrimethy-lammonium chloride, together with AICI3 and sodium chloride (working electrode Pt, counter electrode Pt wire, Al wire in melt). The addition of S OCI2 was required in order to reduce Na+. At — 2.4 V the deposition of sodium started and at —1.8 V the reoxidation was observed [5],... 

The simplest amino acid, glycine, would be an ideal starting material for the synthesis of more complicated amino acids but it does not easily form enols or enoiates. The methyl ester of the ben-zaldehyde imine has two electro n-withdra wing groups to help stabilization of the enolate and conjugate addition of acrylonitrile is now possible. The base used was solid potassium carbonate with a quaternary ammonium chloride as phase transfer catalyst. Simple hydrolysis of the alkylated product leads to the extended amino acid. 

One of the oldest techniques for overcoming these problems is the use of biphasic water/organic solvent systems using phase-transfer methods. In 1951, Jarrouse found that the reaction of water-soluble sodium cyanide with water-insoluble, but organic solvent-soluble 1-chlorooctane is dramatically enhanced by adding a catalytic amount of tetra-n-butylammonium chloride [878], This technique was further developed by Makosza et al. [879], Starks et al. [880], and others, and has become known as liquid-liquid phase-transfer catalysis (PTC) for reviews, see references [656-658, 879-882], The mechanism of this method is shown in Fig. 5-18 for the nucleophilic displacement reaction of a haloalkane with sodium cyanide in the presence of a quaternary ammonium chloride as FT catalyst. 

Fig. 5-18. Phase-transfer catalyzed nucleophilic displacement reaction of a haloalkane, R-Cl, with sodium cyanide, Na+CN , to yield a nitrile, R-CN, in the presence of sub-stoichiometric amounts of a quaternary ammonium chloride, Q+CP, as PT catalyst.

These reactions are known to benefit from the addition of phase transfer agents under certain conditions, For example, 3,5,5-trimethylcyclohex-2-enone was cleaved, with loss of one carbon atom as illustrated in equation (14), when Adogen 464 (a quaternary ammonium chloride) was present... 

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