Phthalane, oxidation

In the oxidation of PX and MX, formaldehyde is a degenerate branching intermediate, whereas phthalan is formed from OX ... 

Kinetic and mechanistic investigations on the o-xylene oxidation over V205—Ti02 catalysts were carried out by Vanhove and Blanchard [335, 336] using a flow reactor at 450°C. Possible intermediates like o-methyl-benzyl alcohol, o-xylene-a,a -diol, toluic acid and phthalaldehyde were studied by comparing their oxidation product distribution with that of toluene. Moreover, a competitive oxidation of o-methylbenzyl alcohol and l4C-labelled o-xylene was carried out. The compounds investigated are all very rapidly oxidized, compared with o-xylene, and essentially yield the same products. It is concluded, therefore, that these compounds, or their adsorbed forms may very well be intermediates in the oxidation of o-xylene to phthalic anhydride. The ratio in which the partial oxidation products are formed appears to depend on the nature of the oxidized compounds, i.e. o-methylbenzyl alcohol yields relatively more phthalide, whereas o-xylene-diol produces detectable amounts of phthalan. This... 

Benzylic oxidation. This combination oxidizes substituted toluenes to the corresponding acids and diarylmethanes (including fluorene) into ketones at room temperature in MeCN. Benzyl ethers such as phthalan and isochroman are converted to phthalide and 3,4-dihydroisocoumarin in quantitative yield. 

The hydroperoxides are the primary products of oxidation of phthalane and isochromane [202,203,284,293]. Hydroperoxide is the main product of dioxan oxidation. The decomposition occurs according to... 

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