Brom-maleic acid

K6kuI6 investigated the electrolysis of maleic acid and brom-maleic acid. The former gave acetylene, besides a small quantity of succinic and fumaric acid the latter, on the contrary, gave only hydrobromic acid and carbon monoxide. Like malic fumaric acid, at the beginning of the experiment, gave only pure acetylene, but after the operation had continued... 

Maleic Acid HOOC—CH = CH—COOH Fumaric Acid S3mthesis from Succinic Acid.—Two isomeric acids are known oi the constitution of di-carboxy ethene, or bulen-di-oic acid. They are named maleic acid and fumaric acid. Their synthesis from succinic acid establishes their constitution. Mono-brom succinic acid when... 

Also di-brom succinic acid loses two atoms of bromine and likewise yields maleic acid. 

The reverse of these reactions viz., the conversion of maleic and fumaric acids, by the addition of hydrogen bromide, into mono-brom succinic acid by the addition of two bromine atoms, into di-brom succinic acid and also by the addition of two hydrogen atoms, into succinic acid itself all show these same relations of maleic and fumaric acids to succinic acid and its bromine substitution products and establish the constitution of these isomeric di-basic unsaturated acids as given. The two acids may also be prepared from malic acid which is, in fact, the chief method by which they are prepared. This reaction will be considered later when malic acid itself is studied. 

Brom and isobrom maleic acid. The explanation of the isomerism here is entirely the same as before, one has only to replace an H in the fumaric and maleic acid by a Br. 

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... 

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