The first enantioselective direct α-hydroxylation of β-oxo esters was developed by using phase-transfercatalysis. 1-Indanone-derived 1-adamantyl (1-Ad) β-oxo esters, in the presence of commercially available cumyl hydroperoxide and a cinchonine-based ammonium salt, resulted in the corresponding products with 69–91 % yield and 65–74 % ee. The reaction had also been successfully scaled-up to a gram
An efficient and enantioselective α-electrophilic difluoromethylation of β-keto esters has been achieved by phase-transfer catalysis. This procedure is applicable to different kinds of β-keto esters with a series of cinchona-derived C-2′ aryl-substituted phase-transfer catalysts. The reaction gives the corresponding products in good enantioselectivities (up to 83% ee) and yields (up to 92%) with high
A highly efficient α-hydroxylation of β-ketoesters catalyzed by cupreidine in the presence of cumyl hydroperoxide (CHP) was achieved. The reaction was applied to a wide variety of β-ketoesters to give products in high yields (up to 95%) with excellent enantioselectivities (up to 97% ee). The reaction had been successfully scaled up to a gram quantity and (S)-5-chloro-2-hydroxy-1-oxo-2,3-dihydro-
phase‐transfer catalyst (PTC) can mediate the highlyenantioselectivetrifluoromethylthiolation of β‐ketoesters with the previously developed SCF3 reagent (see scheme). Reactions of indanone‐derived β‐ketoesters occurred with high yield and excellent enantioselectivity with quinine as catalyst. Reactions of tetralone‐ or 1‐benzosuberone‐derived β‐ketoesters occurred with moderate to good enantioselectivity with