A new efficient and selective synthesis of ketones from alkanes or cycloalkanes, CO, and silanes in the presence of aprotic superacids

Article abstract of DOI:10.1007/BF02498161

A new approach to the direct synthesis of ketones from alkanes or cycloalkanes (RH), CO, and silanes is proposed. Ketones were obtained in 50-97% yields from propane, butane, cyclopentane, cyclohexane, and methylcyclopentane on treatment with CO and silanes (Me₄Si, Et₄Si, or m-and p-XC₆H₄SiMe₃, where X = Cl, Me, OMe) in the presence of CX₄ · 2AlBr₃ (X = Br, Cl) superacids at 0 °C. The reactions with m-and p-XC₆H₄SiMe₃ (X = Cl, Me) occur regioselectively to give m-ketones from m-silanes and p-ketones from p-silanes. However, the only product, p-MeOC₆H₄COR, is formed both from m-and p-MeOC₆H₄SiMe₃. The reaction of Cyclo-C₅H₉CO⁺ with BzSiMe₃ results in an organosilicon ketone, Me₃SiCH₂QH₄COC₅H₉, while in the presence of an excess of an acylating system (after alcoholysis), Me₂Si(OR′)CH₂C₆H₄COR is formed.