Fat‐based dibasic acids

Abstract

AbstractAside from “dimer acids” (E.C. Leonard's paper), the best known fat‐based dibasic acids consist of eight product types of which only four are commercially important. These are described in detail in this paper: (a.) Azelaic acid produced from oleic acid by either chrome oxidation or ozonolysis of oleic acid also, “brassylic” acid from mixed 55% erucic‐containing crambe oil fatty acids. (b). Sebacic acid from castor oil or possibly dodecanedioic acid from lesquerolic acid by caustic fusion. (c) C‐21 Dibasic acid by Diels Alder reaction between isomerized TOFA and acrylic acid. (d.) C‐19 Dibasic acids (carboxystearic acids) from oleic acid by carboxylation. (e.) Mixed C‐11/C‐12 Dibasic acids by several routes. Both the alkali cleavage and gentle nitric acid oxidations of certain hydroxy fatty acids (e.g., 12‐hydroxystearic acid from hydrogenation of ricinoleic acid, etc.) can be used to afford mixed C‐11/C‐12 dibasic acids. (f.) Dibasic acid mixtures by nitric acid oxidations. Depending upon conditions, both saturated and unsaturated fatty acids are oxidized to a heterogeneous mixture of mono‐ and dibasic acids by oxidation with nitric acid.