Aminotropones tropolones

We thus conclude that tropolone has a greater degree of stabilization than 2-aminotropone, a rather surprising conclusion perhaps, until it is realized that esters (and thus presumably carboxylic acids) have higher resonance energies than amides . 

Tropone may be converted into tropolone. In one method tropone is first chlorinated and the chlorine atom is then replaced by a hydroxyl group [73]. Alternatively 2-aminotropone is prepared by the action of hydrazine (or hydroxyl amine) on tropone, and the amino-group is then replaced by a hydroxyl group [169,249]. 

Alkoxytropones also resemble esters in that they react with ammonia to give 2-aminotropones [245, etc.] which are vinylogous amides, and, as such, are readily hydrolysed to tropolones by alkali [169,245,etc.]. 

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