Octadecanedioic acid

InteresPng, though hardly of practical value, is the oxidation of 1 -fluorooctadecane by yeast of genus Torulopsis gropengiessen to give a 9% yield of octadecanedioic acid and a 4 5% yield of hexadecanedioic acid [/]... 

DIMETHYL OCTADECANEDIOATE (Octadecanedioic acid, dimethyl ester)... 

ETHYL 1,16-HEXADECANEDICARBOXYLATE (Octadecanedioic Acid, Diethyl Ester)... 

Following the study of the simple coupling of radicals derived from the salt of a single carboxylic acid, it was found that the electrolysis of a mixture of carboxylate anions or of the salts of half esters of dicarboxylic acids increased the synthetic value of the method. This arises from the possibility of the formation of symmetrical and unsymmetrical coupled products of the derived radicals. These anodic syntheses are illustrated in the synthesis of hexacosane (Expt 5.11), sebacic acid (decanedioic acid), octadecanedioic acid and myristic acid (tetra-decanoic acid), in Expt 5.131. 

Octadecanedioic acid. Dissolve 31.5 g (0.145 mol) of methyl hydrogen sebacate in 140 ml of absolute methanol to which 0.4 g of sodium has been added. Electrolyse at 2.0 amps until the pH of the electrolyte is 7.8-8.0 (3.5-4 hours). Work up as described for sebacic acid. Upon distillation, an unsaturated ester passes over at lll-113°C/20mmHg (4.6 g), followed by dimethyl octadecanedioate at 212-219°C/4mmHg (mainly at 214-215°C/4mmHg), m.p. 56 °C (16.5 g, 66%). 

Reflux 6.8 g of the dimethyl ester with a solution of 3.2 g of sodium hydroxide in 150 ml of 80 per cent methanol for 2 hours on a water bath. When cold, filter off the solid and wash it with a little cold methanol. Dissolve the solid in 350 ml of warm water, add concentrated hydrochloric acid to the solution at 60 °C until acidic to litmus, filter off the precipitated acid, wash with a little water and dry at 100 °C. The resulting octadecanedioic acid, m.p. 122°C, weighs 5.3 g (84%). Recrystallisation from absolute methanol raises the m.p. to 124.5 °C. 

Octadecanediamine, 0-00106 Octadecane-1,18-dicarboxylic acid, see 1-00012 Octadecanedioic acid, 0-00107... 

Hydroxyhexadecanoic acid Ac, in H-00274 16-Hydroxyhexadecanoic acid Ac, in H-00276 Octadecanedioic acid, 0-00107 Tetradecanedioic acid Di-Et ester, in T-00031... 

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