Sulfonate leaving groups include a cation chelating moiety, e.g. a polyether or crown ether. The chelating moiety stabilizes the sulfonate leaving group by forming a complex with a cation of a cation-nucleophile combination. The stabilized leaving group is more easily displaced under many conditions than are standard arylsulfonate leaving groups such as the toxyl group. The chelating moiety also favors certain cations depending on the identity of the moiety thereby enhancing the reaction rate with nucleophilic salts containing the preferred cation. Use of the inventive leaving groups results in improved yields, decreased reaction times and improved product purity.
[EN] Sulfonate leaving groups include a cation chelating moiety, e.g. a polyether or crown ether. The chelating moiety stabilizes the sulfonate leaving group by forming a complex with a cation of a cation-nucleophile combination. The stabilized leaving group is more easily displaced under many conditions than are standard arylsulfonate leaving groups such as the tosyl group. The chelating moiety also favors certain cations depending on the identity of the moiety thereby enhancing the reaction rate with nucleophilic salts containing the preferred cation. Use of the inventive leaving groups results in improved yields, decreased reaction times and improved product purity. [FR] Des groupes labiles sulfonates comprennent une fraction chélatante de cation, par exemple, un polyéther ou un éther couronne. La fraction chélatante stabilise le groupe labile sulfonate par formation d'un complexe avec un cation d'une combinaison cation-nucléophile. Le groupe labile stabilisé est plus facilement déplacé dans bon nombre de conditions que des groupes labiles arylsulfonates standards, tels que le groupe toxyle. La fraction chélatante favorise également certains cations, en fonction de l'identité de la fraction, favorisant ainsi la vitesse de réaction avec des sels nucléophiles contenant le cation préféré. L'utilisation des groupes labiles selon l'invention permet d'obtenir des rendements améliorés, des temps de réaction réduits et une pureté améliorée du produit.