Highly Efficient Preparation of Selectively Isotope Cluster-Labeled Long Chain Fatty Acids via Two Consecutive C_sp³–C_sp³ Cross-Coupling Reactions

An efficient synthesis involving two copper-catalyzed alkyl–alkyl coupling reactions has been designed to easily access doubly isotope-labeled fatty acids. Such NMR- and IR-active compounds were obtained in excellent overall yields and will be further used for determining the conformation of an alkyl chain of lipidic biomolecules upon interaction with proteins.