1-(2-methylphenyl)butane-1,3-dione

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: In the reaction of diketene with aromatic compounds that are solid at room temperature, for example acenaphthene, pyrene, or 2,6-dimethoxynaphthalene, solvents have to be added which do not react with diketene. The aforesaid literature references do not contain any description of corresponding experiments. In proper experiments with 1,2-dichloroethane it has been found that with acenaphthene the yield is drastically reduced and resinifications do occur and that the aluminum chloride-butanedione complexes with pyrene have a high stability. If, however, the diketene is transformed into acetoacetyl fluoride which is then reacted with toluene in the presence of aluminum chloride in chloroform, a yield of 6.5 % only of 1-tolyl-butane-1,3-dione is obtained, calculated on the diketene (cf. G. A. Olah and S. J. Kuhn, J.Org. Chem. 26, page 225 (1961)). at room temperature to be added which