Silver oxide with active hydrogen

Isatin (190) is a compound with interesting chemistry. It can be iV-acetylated with acetic anhydride, iV-methylated via its sodium or potassium salt and O-methylated via its silver salt. Oxidation of isatins with hydrogen peroxide in methanolic sodium methoxide yields methyl anthranilates (81AG(E)882>. In moist air, O-methylisatin (191) forms methylisatoid (192). Isatin forms normal carbonyl derivatives (193) with ketonic reagents such as hydroxylamine and phenylhydrazine and the reactive 3-carbonyl group also undergoes aldol condensation with active methylene compounds. Isatin forms a complex derivative, isamic acid (194), with ammonia (76JCS(P1)2004). 

These results are to be contrasted with tho.se obtained with solid catalysts such as copper, copper oxide, silver oxide, barium peroxide, platinum oxide, and active charcoal in which only very small amounts of hydrogen and carbon monoxide were obtained. From the fact that rather high yields of oxygenated compounds could also be obtained with the gaseous catalyst, it would seem that decomposition of these compounds played ail important part in the production of the hydrogen and carbon monoxide. 

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