Azelaic acid, ozonization

Carbon—nitrogen double bonds in imines, hydrazones, oximes, nitrones, azines, and substituted diazomethanes can be cleaved, yielding mainly ketones, aldehydes and/or carboxyHc acids. Ozonation of acetylene gives primarily glyoxal. With substituted compounds, carboxyHc acids and dicarbonyl compounds are obtained for instance, stearoHc acid yields mainly azelaic acid, and a smaH amount of 9,10-diketostearic acid. 

Cleavage of an alkenoic acid can be carried out with permanganate, a permanganate—periodate mixture, periodate or with nitric acid, dichromate, ozone, or, if the unsaturation is first converted to a dihydroxy compound, lead tetraacetate (71,73). Oxidative ozonolysis is a process for the manufacture of azelaic acid [123-99-9] and pelargonic acid (74). 

There has been only one major use for ozone today in the field of chemical synthesis the ozonation of oleic acid to produce azelaic acid. Oleic acid is obtained from either tallow, a by-product of meat-packing plants, or from tall oil, a byproduct of making paper from wood. Oleic acid is dissolved in about half its weight of pelargonic acid and is ozonized continuously in a reactor with approximately 2 percent ozone in oxygen it is oxidized for several hours. The pelargonic and azelaic acids are recovered by vacuum distillation. The acids are then esterified to yield a plasticizer for vinyl compounds or for the production of lubricants. Azelaic acid is also a starting material in the production of a nylon type of polymer. 

Ozone, when combined with hydrogen peroxide [101] or peroxyacetic acid [268], cleaves the triple bond to yield carboxylic acids. Stearolic acid is converted into a mixture of pelargonic acid and azelaic acid [268] (equation 474). 9-Octadecynedioic acid, on treatment with ozone in acetic acid at room temperature followed by oxidation with hydrogen peroxide, gives azelaic acid in 81% yield [101]. 

The cleavage of oleic acid to azelaic acid and pelargonic acid with ozone as oxidant is one of the important industrial applications of ozonolysis [2]. However, finding a catalytic alternative to this unsuitable and hard-to-handle oxidant is in the interests of research groups all over the world. The cleavage of internal C=C double bonds by use of a Re, Mo, or W catalyst with H2O2 as oxidant, or a Ru catalyst with peracetic acid [12], is known. 

Azelaic acid can be prepared by the oxidation of castor oil with nitric acid by the oxidation of ricinoleic acid with nitric acid and with alkaline permanganate by the oxidation of methyl oleate with alkaline permanganate by the ozonization of oleic acid and decomposition of the ozonide by the ozonization of methyl ricinoleate and decomposition of the ozonide by the action of carbon dioxide upon 1,7-heptamethylene magnesium bromide by the hydrolysis of i,7-di(yanoheptane. ... 

Oxidative cleavage of the double bond in tall oil derived fatty acid may be carried out with ozone pelargonic and azelaic acids are the major acids formed (36). 

Azelaic Acid from Vegetable Feedstock via Oxidative Cleavage with Ozone or Oxygen... 

Azelaic acid (nonanedioic) is produced along with pelargonic acid (nonanoic) by ozonolysis of oleic acid. Oleic acid mixed with nonanoic acid is fed into an ozone absorber against a flow of oxygen gas containing about 2% of ozone. Ozonation occurs at 25-45 °C and external cooling is required. The product is decomposed and oxidized in another vessel at 100 °C (Section 10.4.3). The product is distilled to remove nonanoic and other low-boiling acids and azelaic acid is recovered from the residue by extraction with hot water in which it is soluble. 

Only one fiber and a series of thermoplastic copolyureas are manufactured commercially. For the fiber, one starts with 1,9-nonane diamine, obtained in the following way Rice-bran oil contains a large amount of oleic acid, (CH3—(CH2)7—CH=CH—(CH2)7—COOH), and linoleic acid, (CH3—azelaic acid (HOOC—(CH2)7—COOH). Ammonia is added to this, then water is eliminated during the formation of 1,7-heptane dinitrile, and 1,9-nonane diamine is obtained from this by hydrogenation. Polynonane urea has a melting point of 240 C and possesses better resistance to alkalis than, for example, poly(ethylene terephthalate). It can be dyed satisfactorily with acid dyestuffs. 

Azelaic acid (nonanedioic acid, 1,7-heptane-dicarboxylic acid) n. HOOC(CH2)7COOH. A yellowish-white crystalline powder, derived from a fatty acid such as oleic acid by oxidation with ozone. It is an intermediate used in the production of plasticizers, polyamides and alkyd resins. Acid value, 595.5 mol wt, 188.2 mp, 106°C bp, 237°C/15mmHg. For plasticizers derived from azelaic acid. Merck Index (2001) 13th edn. Merck and Company Inc., Whitehouse Station, NJ. 

Unsaturated fatty acids are susceptible to degradation by ozone. This reaction is practiced in the production azelaic acid ((CH2)7(C02h)2) from oleic acid. 

The ability of ozone to destroy the double C=C bonds in organic compounds is the reason for its wide application in the preparation of bifunctional compounds. This is the principle that lies in the organization of the manufacture of dodecanedicarboxylic acid (1) and azelaic acid (2). The initial substrate for the preparation of (1) is cyclododecane which is obtained from the trimerization of butadiene and partial hydrogenation and (2) is prepared on the base of oleic acid ... 

Cyanide Wastes. Ozone is employed as a selective oxidant in laboratory-scale synthesis (7) and in commercial-scale production of specialty organic chemicals and intermediates such as fragrances, perfumes (qv), flavors, antibiotics (qv), hormones (qv), and vitamins (qv). In Japan, several metric tons per day (t/d) of piperonal [120-57-0] (3,4-methylenedioxybenzaldehyde) is manufactured in 87% yield via ozonolysis and reduction of isosafrole [93-16-3], Piperonal (or heHotropine [120-57-0]) has a pleasant odor and is used in perfumery. Oleic acid [112-80-1/, CH3(CH2 )7CH—CH(CH2 ). C02H, from tall oil (qv) is ozonated on a t/d scale to produce pelargonic, GgH2yG02H, and azelaic, H02G(GH2)yG02H, acids. Oleic acid also is ozonated in Japan... 

The trend is toward oxidants that are relatively harmless and that generate no noxious by-products. Oxygen, and materials derived from it, are examples. Ozone is quite toxic itself, but produces no harmful by-products. It is used commercially for the cleavage of oleic acid to azelaic and pelargonic acids.158 Hydrogen peroxide is made from oxygen (4.23).159... 

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