Heiko Brunner

Iron Trichloride and Air Mediated Guanylation of Acylthioureas. An Ecological Route to Acylguanidines: Scope and Mechanistic Insights

Recently we introduced iron trichloride as an environmentally benign and cost-efficient reagent for the synthesis of N-benzoylguanidines. This highly attractive synthetic approach grants access to a broad spectrum of N-benzoylguanidines under mild conditions in short reaction times. In this work we present an extended scope of our methodology along with the results obtained from mechanistic studies via in situ IR spectroscopy in combination with LC (liquid chromatography)-MS analyses. On the basis of these new mechanistic insights we were able to optimize the synthetic protocol and to develop an alternative mechanistic proposal. In this context the symbiotic roles of iron trichloride and oxygen in the guanylation process are highlighted.

A new and environmentally benign synthesis of aroylguanidines using iron trichloride

A new synthetic approach for the guanylation of aroylthioureas using iron trichloride is presented. Our synthetic method distinguishes itself by benign reaction conditions, low costs and a broad product spectrum. The scope of the reaction and calorimetric studies are described.