Highly selective synthesis of (E)-alkenyl-(pentafluorosulfanyl)benzenes through Horner–Wadsworth–Emmons reaction
نویسندگان
چکیده
Diethyl 2-nitro-(pentafluorosulfanyl)benzylphosphonates, available by the vicarious nucleophilic substitution reaction of meta- and para-nitro-(pentafluorosulfanyl)benzenes and diethyl chloromethylphosphonate, undergo Horner-Wadsworth-Emmons reaction with aldehydes in the presence of potassium hydroxide in acetonitrile at ambient temperature to give (E)-2-nitro-1-alkenyl-(pentafluorosulfanyl)benzenes in good yields and high stereoselectivities. Follow-up transformations of the primary products provided (E)-1-alkenyl-(pentafluorosulfanyl)benzenes and 2-(2-arylethyl)-(pentafluorosulfanyl)anilines.
منابع مشابه
Use of lithium hexafluoroisopropoxide as a mild base for Horner-Wadsworth-Emmons olefination of epimerizable aldehydes.
[reaction: see text] The weak base lithium 1,1,1,3,3,3-hexafluoroisopropoxide (LiHFI) is shown to be highly effective as a reagent for intermolecular Horner-Wadsworth-Emmons (HWE) olefination of epimerizable aldehydes with trimethyl phosphonoacetate, affording products with little or no epimerization and notably high E-selectivity.
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