Hydrogen Peroxide → Azelaic Acid

Participants

Reaction Conditions

Reaction Steps

Into the same apparatus as in Example 1, 100 g of crude methyl oleate (82% purity) containing 9.9% methyl linoleate, 0.75 g of H2WO4 and 1.25 g of dihydroxystearic acid is added. The stirred mixture is brought to 60°-65° C. and 28.6 g of 60% w/w H2O2 is added. The H2O2 is gradually added over about 30 mins in order to maintain the temperature between 60°-70° C. Once the addition of H2O2 is completed the mixture is left at that temperature for another 4 hours. The crude reaction product so obtained is charged into a stirred 500 ml autoclave containing 150 ml of water and 1.0 g of hydrous cobalt chloride. The autoclave is then pressurised with 75 atm of air and the temperature is raised to 65° C. The reaction mixture is stirred at this temperature for 7 hours. At the end, NaOH is added to the reaction mixture until an alkaline pH is reached and saponified for 2 hours at 95° C. After acidification with sulphuric acid, the crude reaction products are treated in the same way as described in example 1. 40.8 g of azelaic acid (yield=70%) and 33.5 g of pelargonic acid (yield=68.8%) are obtained.

Provenance & Evidence