Enantioselective Synthesis of anti-Propionate Aldols via Radical Addition

Significance

Currently, there are relatively few methods for the synthesis of anti-propionate aldols with extremely high diastereo- and enantio­selectivity. Furthermore, standard aldol reactions are performed under basic conditions; limiting the functional group compatibility of the reagents. This method employs radical addition under neutral and fairly mild reaction conditions, providing products with extremely high diastereoselectivity (generally >95:5 anti/syn) and good enantioselectivity (generally >70% ee). This high degree of selectivity was obtained with various Mg²⁺-based Lewis acids, alkyl halides, and vinylic substituents, presenting an interesting new route towards aldol-like products.