The methyl groups of p-substituted acetophenones and the methylene groups of β-diketones were acetoxylated with (diacetoxyiodo) benzene. When the substrates were p- chloroacetophenone, p-nitroacetophenone and 4, 4, 4-trifluoro-1-phenyl-1, 3-butanedione, the corresponding acetoxylated compounds were obtained in high yields.