Benzyl trimethylammonium fluoride

Later benzyl fluoride was prepared by the decomposition of benzyl trimethylammonium fluoride ... 

An efficient method for the generation of o-quinodimethanes via desilylation reaction involves treatment of a 2-[(trimethylsilylmefi3yl)benzyl]trimethylammonium iodide with fluoride ion (equation 31). This reaction was applied by Saegusa and coworkers for the synthesis of estrone in which an intramolecular Diels-Alder reaction of an o-quinodimethane, generated in situ, served as the key reaction (equation 32). ... 

One of the more fundamental methods for generation of the o-xylylene intermediate is 1,4-elimination from o-xylene derivatives. o-Xylene di-, tri-, or tetrabromides undergo intramolecular 1,4-dehalogenation by means of sodium iodide [102], lithium [103], zinc [104], copper [105], iron [106], and chromium [107]. Hoffman degradation of (o-methylbenzyl)trimethylammonium hydroxides [108], as well as the more recently developed fluoride ion-induced elimination from [o-[a-(trimethylsilyl)alkyl]benzyl]trimethylammonium halides [109], have also been effectively utilized in the generation of 2. 

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