Synthesis of [14,14,14-2H3] 12-hydroxytetradecanoic acid and [13,14-2H2] 11-hydroxytetradecanoic acid useful as tracers to study a (11E)-desaturation reaction in Spodoptera littoralis.

The synthesis of deuterium labeled 11- and 12-hydroxytetradecanoic acids to study a (11E) desaturase in the moth Spodoptera littoralis is reported. [14,14,14-2H3] 12-hydroxytetradecanoic acid was synthesized in four steps from 11-iodo-1-undecene in 49% overall yield. Deuterium was introduced by reaction of an epoxy ester with (CD3)2CuLi. The preparation of [13,14-2H2] 11-hydroxytetradecanoic acid was carried out in six steps from 11-bromoundecanoic acid in 55% overall yield. In this case, label was introduced by deuteration of an homoallyl alcohol with D2, using the Wilkinson catalyst. Incubation of pheromone glands with either of both acids did not lead to the formation of the labeled (11E)-tetradecenoic acid.