A convenient laboratory method for preparing<i>trans, trans</i>‐9, 11‐octadecadienoic acid

Abstract

Abstract A convenient laboratory method to prepare trans,trans ‐ 9,11‐octadecadienoic acid (TTA) via a polyester intermediate is described. Ricinelaidic acid was heated at 235C under vacuum for 3–4 hr to form a polyester having a mol wt of 1,500–1,600. Pyrolysis of this polyester and simultane‐ous distillation of the products gave crude dehy‐drated acids. TTA was crystallized from a 95% ethanol solution of these acids, in a yield of 35%. Of the variables affecting pyrolysis, the mol wt of polyester had the greatest effect on yield of TTA.