Direct Access to Mono-Protected Homoallylic 1,2-Diols via Dual Chromium/ Photoredox Catalysis

A dual catalytic strategy enables the efficient synthesis of mono-protected homoallylic 1,2-diols by coupling abundant aldehydes with simple (silyl) enol ethers, thus providing direct access to this important motif without the (super)stoichiometric use of prefunctionalized metal-allyl species. A variety of silyl- and alkyl-based protecting groups is shown and functional group tolerance, chemoselectivity and scalability are highlighted.