Adducts of an anion of an oxa acid and a keto compound, process for the preparation of said adducts, and process for the determination of the concentration of the anions of oxa acids using said keto compounds

摘要

Keto compounds in which to the carbon atom in the neighboring position to the keto compounds there is bonded at least one strongly electron attracting substituent and/or in which there is conjugating with the carbon-oxygen-double bond of the keto group a -electron system have the ability of interacting selectively with the anions of oxa acids yielding adducts, chelates or complexes.PPProvided that in the corresponding keto compounds the keto group is a part of a chromophore, then the shifting of the absorption in the visible range or the ultraviolet range of the wave lengths is observed, compared with the corresponding absorption of the free keto compound.PPThe corresponding keto compounds are used for the determination of the anions of the oxa acids and they e.g. can be the ion sensitive component of a corresponding ions sensitive part for the determination of said anions. Several of said keto compounds can be also used as color indicator for the anions of the oxa acids.