Rhodium-Catalyzed, Enantioselective Hydroacylation of ortho-Allylbenzaldehydes

The development of a rhodium catalyst for endo- and enantioselective hydroacylation of ortho-allylbenz­aldehydes is reported. A catalyst generated in situ from [Rh­(COD)­Cl]₂, (R)-DTBM-SEGPHOS, and NaBARF promotes the desired hydroacylation reactions and minimizes the formation of byproducts from competitive alkene isomerization and ene/dehydration pathways. These rhodium-catalyzed processes generate the 3,4-dihydro­naphthalen-1­(2H)-one products in moderate-to-high yields (49–91%) with excellent enantioselectivities (96–99% ee).