Ammonium salts, quaternary preparation

IMtfilion Polymeric quaternary ammonium salt prepared by the reaction of DMAPAacrylates/acrylic acid/acrylonitrogens copolymer and diethyl sulfate... 

Lauryl methyl gluceth-10 hydroxypropyidimonium chloride Definition Quaternary ammonium salt prepared by reaction of methyl gluceth-10 with a dimethyl dodecylammonium substituted epoxide Uses Antistat, substantivity agent, conditioner, humectant, moisturizer for cosmetics, topical pharmaceuticals... 

Definition Polymeric quaternary ammonium salt prepared by reaction of ethyl methacrylate/abietyl methacrylate/diethylaminoethyl methacrylate copolymer with dimethyl sulfate Uses Antistat, film-former in cosmetics Polyquaternium-13 CAS 68877-47-4... 

Definition Polymeric quaternary ammonium salt prepared by reaction of polyvinyl alcohol with 2,3-epoxypropylamine... 

The same authors conducted systematic studies of a-methylation and proposed the tight ion-pair complex 4 as an intermediate, formed through hydrogen bonding and electrostatic n-n stacking interactions, accounting for the chiral induction. Enantioselective a-methylation has been recognised as the first attempt at asymmetric phase-transfer catalytic all lation in the presence of a quaternary ammonium salt prepared from cinchonine as a catalyst. 

Girard s reagent T is carbohydrazidomethyltrimethylammonium chloride (I) and is prepared by the reaction of the quaternary ammonium salt formed from ethyl chloroacetate and trimethylamine with hydrazine hydrate in alco-hoUc solution ... 

Amines are powerful nucleophiles which react under neutral or slightly basic conditions with several electron-accepting carbon reagents. The reaction of alkyl halides with amines is useful for the preparation of tertiary amines or quaternary ammonium salts. The conversion of primary amines into secondary amines is usually not feasible since the secondary amine tends towards further alkylation. 

Because of its high reactivity toward nucleophilic substitution methyl iodide is the alkyl halide most often used to prepare quaternary ammonium salts... 

The Leuckart reaction uses formic acid as reducing agent. Reductive alkylation using formaldehyde, hydrogen, and catalyst, usually nickel, is used commercially to prepare methylated amines. These tertiary amines are used to prepare quaternary ammonium salts. 

Another significant use for dialkyl dimethyl quaternary ammonium salts and alkylhenzyl dimethyl ammonium salts is in preparing organoclays for use as drilling muds, paint thickeners, and lubricants. 

Quaternary ammonium alkyl ethers are prepared similarly an alkaline starch is reacted with a quaternary ammonium salt containing a 3-chloto-2-hydtoxyptopyl or 2,3-epoxyptopyl radical. Alternatively, such derivatives can be prepared by simple quaternization of tertiary aminoalkyl ethers by reaction with methyl iodide. Sulfonium (107) and phosphonium (108) starch salts have also been prepared and investigated. Further work has explained the synthesis of diethyl aminoethyl starch (109) as well as the production of cationic starches from the reaction of alkaline starch with... 

The ring-chiorinated benzyl chlorides are used ia the preparation of quaternary ammonium salts and as iatermediates for pharmaceuticals and pesticides. p-C. orohen zyl chloride is an iatermediate ia the manufacture of the rice herbicide, Saturn ((S-4-chlorobenzyl)-N,N-diethylthiolcarbamate [28249-77-6] (75). The o- and -chlorobenzal chlorides (l-chloro-2-and 4-dich1 oromethylhenzenes) are starting materials for the manufacture of o- and p- chlo rob enz aldehyde s. 

The amino functional group is not commonly encountered in steroid synthesis except perhaps in steroidal alkaloids. However, certain elimination reactions have been shown to have theoretical and limited preparative importance, largely due to the efforts of McKenna and co-workers. The Hofmann rule for 2 elimination predicts that alkaline elimination of quaternary ammonium salts will occur towards the carbon carrying the most hydrogen atoms cf. the converse Saytzeff orientation, above). In cyclohexyl systems, the requirement for diaxial elimination appears to be important, as in other 2 eliminations, and the Hofmann rule frequently is not obeyed [e.g., (116) (117)]. 

When potassium fluoride is combined with a variety of quaternary ammonium salts its reaction rate is accelerated and the overall yields of a vanety of halogen displacements are improved [57, p 112ff. Variables like catalyst type and moisture content of the alkali metal fluoride need to be optimized. In addition, the maximum yield is a function of two parallel reactions direct fluorination and catalyst decomposition due to its low thermal stability in the presence of fluoride ion [5,8, 59, 60] One example is trimethylsilyl fluoride, which can be prepared from the chloride by using either 18-crown-6 (Procedure 3, p 192) or Aliquot 336 in wet chlorobenzene, as illustrated in equation 35 [61],... 

Quaternary ammonium salts of pyrrolines 106) can be prepared only indirectly 197). Addition of bromine to l-dimethylamino-4-pentene followed by removal of hydrogen bromide afforded, depending upon the dehydrohalogenation conditions, quaternary bromides derived from either l,2-dimethyl-/f -pyrroline (107) or l-methyl-2-methylenepyrrolidine (108) (Scheme 7). 

Amine oxides 2, which can be prepared by oxidation of amines 1, react upon heating to yield an olefin 3 and a hydroxylamine 4. This reaction is called the Cope elimination reaction,and as a synthetic method is a valuable alternative to the Hofmann degradation reaction of quaternary ammonium salts. 

The preparation of an alkene 3 from an amine 1 by application of a /3-elimination reaction is an important method in organic chemistry. A common procedure is the Hofmann elimination where the amine is first converted into a quaternary ammonium salt by exhaustive methylation. Another route for the conversion of amines to alkenes is offered by the Cope elimination. 

Methyl vinyl ketone 2 tends to polymerize, especially in the presence of a strong base the yield of annulation product is therefore often low. A methyl vinyl ketone precursor, e.g. 6, is often employed, from which the Michael acceptor 2 is generated in situ, upon treatment with a base. The quaternary ammonium salt 6 can be obtained by reaction of the tertiary amine 5, which in turn is prepared from acetone, formaldehyde and diethylamine in a Mannich reaction. 

Oxonium ions are excellent alkylating agents, and ethers can be conveniently prepared by treating them with alcohols or phenols. Quaternary ammonium salts can sometimes also be used. ... 

Quaternary ammonium salts of 1-acryloy 1-4-methyl piperazine can be prepared by methylation with methyl chloride and dimethyl sulfate. These monomers can be polymerized by means of radical polymerization, either alone or with a comonomer [617]. A useful comonomer with appropriate monomer reactivity ratios is acrylamide. 

Transformations to polymer-bound amino compounds, which are often useful as ligands for metals ions or other free species (67), employ a wide selection of organic reactions. Quaternary ammonium salts result from heating isolated polymer tosylate with tertiary amine they may also be prepared in one step from (hydroxyethyl)polystyrene and toluenesulfonyl chloride and a two-fold excess of amine. 

Aryl vinyl ketones are produced thermally from the corresponding quaternary ammonium salts via Hofmann elimination. However, the conjugated ketones are heat-sensitive and polymerization is difficult to avoid. Traditional preparations afforded only moderate yields. Microwave conditions were established for Hofmann eliminations, performed essentially quantitatively, by batch or continuous processes. 

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