P-Methylacetophenone

The p-methylacetophenone is readily prepared by the Friedel-Crafts reaction cf. p. 254), toluene being treated with acetyl chloride in the presence of alumfnium chloride. The toluene is employed in considerable excess so that it... 

An alternative apparatus for conducting the preparation by both methods utilises a two-way adapter as in Fig. II, 13, 9. The preparation may be carried out more conveniently in a three-necked flask provided with a mechanical stirrer full details are given below under p-methylacetophenone. 

Tetrachloro-4-methylacetophe-none from aluminum chloride catalyzed chlorination of p-methylacetophenone, 40, 10... 

Thus we would expect the phosphorescence efficiency to be greater for the first case than the second. In agreement with this conclusion, Similar effects are observed for heterocycles for example, the phosphorescence quantum yield for pyrazine (lowest n, it triplet) is 0.30(119) while that for quinoline in a hydroxylic solvent (lowest 77,77 triplet) is 0.19/305... 

Photolytic. A n-hexane solution containing /n-xylene and spread as a thin film (4 mm) on cold water (10 °C) was irradiated by a mercury medium pressure lamp. In 3 h, 18.5% of the p-xylene photooxidized into p-methylbenzaldehyde, p-benzyl alcohol, p-benzoic acid, and p-methylacetophenone (Moza and Feicht, 1989). Glyoxal and methylglyoxal were produced from the photooxidation of p-xylene by OH radicals in air at 25 °C (Tuazon et al., 1986a). The rate constant for the reaction of p-xylene and OH radicals at room temperature was 1.22 x lO " cmVmolecule-sec (Hansen et al., 1975). A rate constant of 7.45 x 10 L/molecule-sec was reported for the reaction of p-xylene with OH radicals in the gas phase (Darnall et al, 1976). Similarly, a room temperature rate constant of 1.41 x 10 " cm /molecule-sec was reported for the vapor-phase reaction of p-xylene with OH radicals (Atkinson, 1985). At 25 °C, a rate constant of 1.29 x lO " cmVmolecule-sec was reported for the same reaction (Ohta and Ohyama, 1985). 

Di-/ -butyl phthalate 4-Methylacetanilide, p-Toluidine Methyl acetate, see Methvl tert-butvl ether Methylacetoacetate, see Mevinphos o-Methylacetophenone, see o-Xylene /n-Methylacetophenone, see ro-Xylene p-Methylacetophenone, see p-Xylene... 

The liquid-phase oxidation of p-methylacetophenone is important from practical and methodological points of view and deserves a concise consideration. The reaction is performed in acetic acid with the cobalt acetate catalyst. As shown by Obukhova et al. (2002), the catalyst detaches an electron from the substrate. The latter forms the cation-radical, which can dissociate in the following two ways ... 

Acetic acid has been found to react with toluene to form p-methylace-tophenone (Simons et al., 49), to react with benzene to form acetophenone, and to react with phenol to form p-hydroxy acetophenone. Acetyl chloride also formed acetophenone with benzene and acetic anhydride reacted with toluene to form both p-methylacetophenone and 2,4-diace-tyltoluene. Valeric acid reacted with toluene to form p-tolyl-n-butyl ketone. Both benzoic acid and benzoyl chloride reacted with toluene to form p-tolylphenyl ketone. Acenaphthene with either benzoic acid or benzoyl chloride gave 3-benzoylacenaphthene (Fieser and Hershberg,... 

---