Trans-Glutaconic acid

Reaction between Deuterium Oxide and cis- and trans-Glutaconic Acids. J. chem. Soc. [London] 1939, 1673. 

However in certain cases no reagent is used shows that the mechanism is not so simple. Further in the conversion of cis glutaconic acid into the trans form has thrown light that unexpected phenomena may occur in what seem to be very simple reactions and may sometimes lead to erroneous conclusions. 

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