Stereoconservative Selective Monodehalogenation of gem‐ Dihalohydrins Using Vitamin B2 Photocatalysis

ABSTRACT

The boundaries of reductive dehalogenations are being pushed forward with the power of visible light. Flavin derivatives absorb in the blue region and offer unique redox properties that allowed us to collect two photons and two electrons from cheap sacrificial donors in order to form super‐reducing excited flavin species. This enabled the highly selective monodebromination of nonactivated chiral gem‐ dihalohydrins (Br, Cl, F) with no erosion in the enantiomeric purity and resulted readily tolerant with often sensitive functional groups. Moreover, the reaction is compatible with other catalysts such as enzymes, which permits the design of multistep synthetic routes for the construction of molecular scaffolds with more than one stereocenter.