Addition reactions of alkenes with electronegatively substituted alcohols in the presence of xenon difluoride

Abstract

The electrophilic reactivity of proposed alkoxyxenon fluoride (ROXeF) intermediates based on electronegatively substituted (polyfluorinated and polynitroaliphatic) alcohols has been characterized with model alkenes norbornene, 2-methylpent-1-ene and hex-1-ene. The alkoxyxenon fluorides can react as positive oxygen electrophiles—initially incorporating alkoxy substituents—or as apparent fluorine electrophiles—resulting in initial fluorine incorporation—depending on conditions. Efficient simple addition of poorly nucleophilic alcohols to norbornene was observed in certain systems. Selectivity between the various reaction paths (simple fluorination, alkoxyfluorination or alcohol addition) was observed to be a sensitive function of various reaction conditions, especially solvent, temperature and catalyst.