AbstractStudies were conducted in the synthetic conversion of oleic acid to mid‐chain branched fatty acids. Methyl oleate was brominated in the allylic positions. Reaction of the allylic bromides with lithium dimethylcuprate gave primarily the desired branched‐chain derivatives (93% of product mixture). The product had a significantly lower crystallization temperature in comparison with methyl oleate. Reaction of the allylic bromides with lithium di‐n‐butylcuprate or lithium di‐sec‐butylcuprate also gave branched‐chain derivatives, but in this instance there was the complication of attack on the ester functionality in the fashion of a Grignard reagent. Details of the syntheses and the properties of the products (with emphasis on low‐temperature properties) are discussed.