Year: 2026
Type: preprint
Abstract: Herein, we report the nucleophilic ring-opening of oxiranes with substituted amines using N-heterocycle-substituted iodolium salts (NHISs) as Lewis acid pre-catalysts. Using the ring-opening of styrene oxide by aniline as a model reaction, we demonstrate that NHISs enable efficient β-aminoalcohol formation at room temperature and with pre-catalyst loadings as low as 2.5 mol%. The optimized protocol was successfully applied to a broad range of substituted oxiranes and amines, affording the corresponding β-aminoalcohols in isolated yields of up to 98%. Based on control experiments and recent literature examples, we show that the iodolium salt is not a simple spectator but, under the reaction conditions, undergoes an amine-induced intramolecular aryl–aryl coupling to generate an electron-deficient iodoarene and an ammonium borate salt in situ. On this basis, we propose a dual activation mechanism in which halogen-bond (XB) donor activation of the epoxide operates in concert with an in situ generated β-hydroxyammonium co-catalyst.
Source: ChemRxiv
Institution: University of Bremen
Language: English
Subfield: Organic Chemistry
Field: Chemistry
Domain: Physical Sciences
Open Access status: green
Award: G6445963889
OpenAlex ID: W7222606670