Synthesis of novel tritium labeled oxamyristic acids

Syntheses of [³H]‐labeled 13‐oxa (⁵) and 6‐oxa (9) myristic acids with specific activity of 137 Ci/mmol and 105 Ci/mmol respectively, starting from the corresponding acetylenic precursors, 12‐methoxy‐10‐dodecynoic acid (4) and 5‐(3‐octynyloxy)pentanoic acid (8) are described. The precursor 4 is readily obtained in high yield by alkylation of the lithium salt of methyl propargyl ether with 9‐iodononanoic acid, whereas 8 is obtained by alkylation of 3‐octyn‐1‐ol with t‐butyl‐5‐bromovalerate under phase transfer conditions, followed by acid catalysed removal of the t‐butyl group.