The synthesis of carbon‐14 labeled 1‐(4,8‐dimethyl‐8‐methoxynonyl)‐4‐(1‐methylethyl)benzene

Abstract The title compound, uniformly labeled with carbon‐14 in the benzene ring, was prepared by Wittig reaction of 4‐isopropyl‐benzaldehyde‐14C ring (U) with 3,7‐dimethyl‐7‐methoxyoctylidene‐tripehylphosphrane followed by catalytic hydrogenation of the resulting mixture of olefins. A second route to the title compound, based on alkyllithium chemistry, was demonstrated using unlabeled intermediates. Attempted preparation of the title compound via the Horner‐Emmons modification of the Wittig reaction was unsuccessful.