Heptoic acid, oxidation

Heptoic acid has been prepared by the oxidation of heptaldehyde with nitric acid, with potassium permanganate in alkaline aqueous solution or in acetone solution, and with potassium dichromate and sulfuric acid. ... 

Hexaldehyde has been prepared from caproic acid by passing it over zinc dust at 300°, by reaction with amylene at 300° in the presence of thorium oxide, by passing it over manganous oxide at 300-360° with two volumes of formic acid, and by distillation of the calcium salt with calcium formate. It has also been prepared by heating a-hydroxyheptoic acid or better a-aceto heptoic acid, and by the reaction of ethyl orthoformate with -amylmagnesium bromide. ... 

HEPTOIC ACID or n-HEPTOIC ACID (111-14-8) Combustible liquid (flash point >221°F/>105°C). Incompatible with sulfuric acid, caustics, ammonia, aliphatic amines, alkanolamines, isocyanates, alkylene oxides, epichlorohydrin. 

Heptanoic Add, Enanthic acid oenanthic add oenanthylic acid n-heptoic add n-heptylic add. C,Hl40, mol wt 130.18. C 64.58%, H 10.84%, O 24.58%. CHj-(CHj)jCOOH. Found in the various fusel oils in appredable amounts. Has been observed in randd oils. Prepd by the oxidation of heptaldehyde with potassium permanganate in dil sulfuric add Ruhoff, Org. Syn. coll. voL II, 3]5 (1943). 

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