The phosphine oxide-catalyzed asymmetric intramolecular aldol reactions of diketones were investigated. The combination of tetrachlorosilane and a chiral phosphine oxide catalyst promoted the ...

When aliphatic 1,2-diketone, such as 3,4-hexanedione was used as substrate, the desired products were also obtained with excellent yield (Table 4, entry 8). Finally, we also examined the reaction of ...