PubReading [76] - The Catalytic Asymmetric Intermolecular Prins Reaction - D. Díaz-Oviedo, R. Maji, and B. List

<p>Despite their significant potential, <strong>catalytic asymmetric reactions</strong> of olefins with formaldehyde are rare and metal-free approaches have not been previously disclosed. Here we describe an enantioselective intermolecular Prins reaction of styrenes and paraformaldehyde to form <strong>1,3-dioxanes</strong>, using confined <strong>imino-imidodiphosphate</strong> (iIDP) Brønsted acid catalysts. Isotope labeling experiments and computations suggest a concerted, highly asynchronous addition of an acid-activated formaldehyde oligomer to the olefin. The enantioenriched 1,3-dioxanes can be transformed into the corresponding optically active <strong>1,3-diols</strong>, which are valuable synthetic building blocks. - <a href="https://doi.org/10.1021/jacs.1c10245" rel="noopener noreferrer nofollow">https://doi.org/10.1021/jacs.1c10245</a> - 2021</p>