Functionalization of saturated hydrocarbons 3. One-step alkylacylation of aromatic hydrocarbons with alkanes (or cycloalkanes) in the presence of aprotic organic superacids

Article abstract of DOI:10.1007/BF00702005

Alkanes and cycloalkanes (isobutane, butane, isopentane, isohexane, and methylcyclopentane) react with benzene or bromobenzene at 0-20 deg C in the presence of RCO⁺Al2X7^- complexes (R = Me, Pr, or Ph; X = Cl or Br) to give products of the alkylation of arenes.The yields of alkylated aromatic ketones reach 60-87percent in 5-30 min, whereas the yields of unalkylated aromatic ketones (the competitive reaction) reach 0-40percent.The reactions of isobutane or isopentane with benzene result exclusively in para isomers of t-BuC6H4COR or a mixture of Me2(Et)CC6H4COR and Me(i-Pr)CHC6H4COR isomers (1:1), respectively.The reaction of isobutane with benzene also proceeds regioselectively and gives only one isomer, 2-Br-t-BuC6H4COR.