Benzylic quaternary ammonium salt

Benzylic quaternary ammonium salts, when treated with alkali metal amides, undergo a rearrangement called the Sommelet-Hauser rearrangementSince the product is a benzylic tertiary amine, it can be further alkylated and the product again subjected to the rearrangement. This process can be continued around the ring until an ortho position is blocked. ... 

Wittig rearrangement of benzylic quaternary ammonium salts upon treatment with alkali metal amides via the ammonium ylide intermediates. 

Following the discovery that xylocholine blocked transmission at sympathetic nerve terminals, intensive chemical and biological investigations of related compounds revealed that various benzyl quaternary ammonium salts were potent and selective inhibitors of adrenergic nerve function. A review of compounds of this type has been published by Copp [239]. A -2-Bromobenzyl-A(-ethyl-A. A-dimethylammonium tosylate (LIII) (bretylium) has been studied extensively [237, 258], and suppression of adrenergic nerve function has been demonstrated in numerous test situations in various animal species. 

Rearrangement of benzylic quaternary ammonium salts (Sommelet-Hauser)... 

Miscellaneous Derivatives. Other derivatives of toluene, none of which is estimated to consume more than ca 3000 t (106 gal) of toluene annually, are mono- and dinitrotoluene hydrogenated to amines benzotnchloride and chlorotoluene, both used as dye intermediates / rf-butylbenzoic acid from /m-butyltoluene, used as a resin modifier, dodecyltoluene converted to a benzyl quaternary ammonium salt for use as a germidde and biphenyl, obtained as by-product during demelhylation, used in specialty chemicals. Toluene is also used as a denaturant in specially denatured alcohol (SDA) formulas 2-B and 12-A. 

Sommelet-Hauser rearrangement The rearrangement of a benzyl quaternary ammonium salt, C6H5CH2N+R3X-, when treated with an alkali metal amide to give the orthomethylbenzyl tertiary amine, o-CH3C6H4CH2NR2. The tertiary amine may subsequently be alkylated, and the reaction... 

Sommelet-Hauser rearrangement. Rearrangement of benzyl quaternary ammonium salts to orr/to-substituted benzyldialkylamines on treatment with alkali metal amides. 

In the presence of NaNH2 benzylic quaternary ammonium salts generally lead to the Sommelet-Hauser rearrangement (refs. 90, 92-104). An ortho alkylation takes place via an exomethylene intermediate. If the two ortho and ortho positions are methylated, the methylene compounds can be isolated (refs. 92, 93). The first anion formed in this reaction can be trapped at a very low temperature (-80 °C) in an aldol reaction for example (ref. 103). At -30°C the isomerization and the rearrangement occur (Fig. 16). 

Other A-benzyl quaternary ammonium salts derived from cinchona alkaloids have been used for the direct addition of malonates to chalcones (Scheme 5.10). In the screening of the reaction, the structure of the catalyst needed some optimization and, after some experiments, the authors identified... 

In the Sommelet—Hauser rearrangement, a benzyl quaternary ammonium salt reacts with a strong base to give a benzyl tertiary amine, as exemplified below ... 

Sigmatropic rearrangements of benzyl quaternary ammonium salts are known as the Sommelet-Hauser rearrangements. The treatment of the benzyl quaternary ammonium salt with sodium amide or other alkali metal amide generates benzyl ammonium ylide. The following examples are illustrative [108, 116-119] ... 

Electrolysis of phenyl and benzyl quaternary ammonium salts. 

Finkelstein.M., Peterson, R.C., Ross,S.D. Electrolysis of phenyl and benzyl quaternary ammonium salts. Electrochim. Acta 10, 465 (1965). 

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