To the best of our knowledge, there is no precedent for the activation of isoureas other than through protonation. During our recent studies on the chemistry of solid-supported O-alkylisoureas, 3 we became interested in exploring new methods for the activation of O-alkylisoureas towards nucleophilic attack. With O-alkylisoureas being easily prepared from the corresponding alcohols, 1 the ultimate aim of the research was to investigate whether alternative ...