Mesa-conic acid

It has been obtained by the oxidation of lactic acid,4 mesa-conic acid and citraconic acid,5 acetone and acetol,6 but in general these oxidation procedures are not suitable as preparative methods. 

Methyl fumaric acid Mesa-conic acid... 

Citra-conic and Mesa-conic Acids.—Two such geometrically isomeric acids are known to which the names citra-conic acid and mesa-conic acid have been given. Citra-conic acid melts at 80° and easily yields an anhydride. It must, therefore, be represented by the cis formula and is the methyl derivative of maleic acid. Mesa-conic acid melts at 202° and does not yield an anhydride. It should, therefore, be... 

Ita-conic Acid.—There is, however, a third acid known of the same composition as the two preceding. It is called ita-conic acid and like the others is obtained from citric acid by distiUation. More than the two isomers just explained are not possible according to geometric isomerism. The isomerism, therefore, of this new acid with the other two must be explained in some other way and has been shown to be structural isomerism due to the different position of the double bond. We have spoken of the fact that both citra-conic and mesa-conic acids, by the addition of hydrogen, are converted into methyl succinic acid. This same result is obtained with ita-conic acid also as may be explained by the following reactions. 

Oxalic acid—Malonic acid—Succinic acid—Glutaric acid— Pyrotartaric acid—Itaconic acid—Citraconic acid—Mesa-conic acid—Malic acid—Tartaric acid—Bourgoin s deductions—K kul maleic, brom-maleic and fumaric acids.. 25-31... 

Citra-conic. Mesa-conic and Ita-conic Acids... 

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