Quaternary ammonium salt, benzoyl

Quaternary ammonium salt, benzoyl-choline chloride and iodide, 10 Quinoxaline, 86, 87... 

Rasmussen and co-workers. Chapter 10, have shown that many free-radical polymerizations can be conducted in two-phase systems using potassium persulfate and either crown ethers or quaternary ammonium salts as initiators. When transferred to the organic phase persulfate performs far more efficiently as an initiator than conventional materials such as azobisisobutyronitrile or benzoyl peroxide. In vinyl polymerizations using PTC-persulfate initiation one can exercise precise control over reaction rates, even at low temperatures. Mechanistic aspects of these complicated systems have been worked out for this highly useful and economical method of initiation of free-radical polymerizations. 

Vinyl monomer polymerization has been photoinitiated with quaternary ammonium salts, an example of the mechanism of which is given in reaction (4), the benzoyl radical being the initiating species.12... 

The influence of protein denaturants (such as alcohols, urea and urea derivatives, and quaternary ammonium salts) on the stability of the compact-coil conformation of PMAA is also described. These protein denaturants, when added to aqueous solutions of PMAA, considerably limit the rate of the neutral hydrolysis of 1-benzoyl-3-phenyl-1,2,4-triazole. 

Excellent examples are found in the hydrolytic reactions of esters with alkalis, the interaction of alkyl halides with hydroxyl ions, the benzoylation of amines, and the union of tertiary amines with alkyl halides to give quaternary ammonium salts. Among gas-phase reactions the decomposition of hydrogen iodide, on the one hand, and the union of hydrogen with iodine on the other provide the classical examples. The absolute rates in this last case are rather closely given by collision number... 

The formation of aldehyde cyanohydrin esters has been achieved under phase transfer catalytic conditions in which the two liquid phases are aqueous sodium or potassium cyanide and a methylene chloride solution of an aromatic aldehyde and an acid chloride. Both quaternary ammonium salts and 18-crown-6 are effective catalysts in this reaction. The formation of aldehyde cyanohydrin esters according to equation 7.7 probably occurs by a mechanism similar to that proposed for the formation of benzoyl cyanide dimers (see Eq. 7.5) [3, 22]. Accordingly, cyanide anion adds to the aldehyde carbonyl group to yield an alkoxide anion which in turn is acylated by the acid chloride. 

Tertiary amines react with alkylating agents with the formation of quaternary ammonium salts. For alkylation, methyliodide, methyl / -toluenesul-fonate, and benzoyl chloride are used. Methyl p-toluenesulfonates are suitable derivatives for the identification of nitrogenated cyclic compounds. The general method of preparation of quaternary ammonium compounds consists of mixing equimolar quantities of the tertiary amine and of the reagent and heating for several minutes. The reaction can also be carried out in an inert solvent (benzene, nitromethane, diisopropyl ether). 

Bis-acyl sulphides are obtained in only low yield by the standard reaction of sodium sulphide with an acyl chloride, but the addition of Adogen results in their viable synthesis with yields >70%. Examples using quaternary phosphonium salts provide the optimum yields (> 90%) [63]. Similarly, thiophenols have been benzoylated using benzoyl chloride under basic conditions in the presence of ammonium salts [12]. 

Halogens are frequently used as oxidation agents and, under two-phase conditions, they can either be employed as ammonium complex halide salts [3], or in the molecular state with or without an added quaternary ammonium catalyst [4]. Stoichiometric amounts of tetra-n-butylammonium tribromide under pH controlled conditions oxidize primary alcohols and low-molecular-weight alkyl ethers to esters, a,cyclic ethers produce lactones [3], and secondary alcohols yield ketones. Benzoins are oxidized to the corresponding benzils (80-90%) by the tribromide salts in acetonitrile in the presence of benzoyl peroxide [5]. 

Complexation with zinc effectively separates the C3S5 dianion from the trithiocarbonate ion in high yield, and the material obtained is sufficiently pure for further reactions. The quaternary ammonium zincate salt is alkylated slowly but smoothly by many halides at room temperature in solvents such as acetone or tetrahydrofuran. Reaction of the zincate with benzoyl chloride followed by cleavage of the resulting benzoate by sodium ethoxide in ethanol provides the much more reactive species NajCaSs. The sodium salt is, however, very air sensitive,5 whereas the zinc salt is completely stable. 

N,N-Dimethyl-N-[3-[(1-oxoisooctadecyl) amino] propyl] benzenemethaminium chloride. See Isostearaminopropalkonium chloride N,N-Dimethyl-N-[3-[(1-oxooctadecyl) amino] propyl] benzenemethanaminium chloride. See Stearamidopropalkonium chloride 2-(2,2-Dimethyl-1-oxopropyl)-1H-indene-1,3(2H)-dione. See Pivalyl indandione Dimethyloxostannane. See Dimethyltin oxide Dimethyloxychinizin. See Antipyrine 2,2-Dimethyl-4-oxymethyl-1,3-dioxolane. See 2,2-Dimethyl-1,3-dioxolane-4-methanol Dimethyloxyquinazine. See Antipyrine Dimethyl PABA ethyl cetearyidimonium tosylate Synonyms Quaternary ammonium compds., N-C16-C18-alkyl-N-[2-(4-dimethylaminobenzoyloxy) ethyl]-N,N-dimethyl-, salt with 4- methylbenzenesulfonic acid Quaternary ammonium compds., N-C16-C18-alkyl [2-[[4-(dimethylamino) benzoyl] oxy] ethyl] dimethyl, salt with p-toluenesulfonic acid... 

The investigation of benzoyl peroxide decomposition in the presence of quaternary ammonium halides has shown that the nature of anion as well as cation of the onium salt influenced the peroxide substrate decomposition. Authors [19] have proposed the association model of diacylperoxides decomposition activation by onium salts (Fig. 4). 

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