Phytone (XI), an important intermediate in the preparation of α-tocopherol, was synthesized by a selective Wittig reaction between geranyltriphenylphosphonium halide (VII) and the aldehyde group of 2-methyl-6-oxoheptanal (VIII), followed by the hydrogenation of the product. VIII was prepared from 1, 3-dimethyl-1-cyclohexene (V) by ozonolysis and reductive decomposition. V could not be obtained in a pure state by the dehydration of 2, 6- ...
