a Farnesol → Isophytol

Participants

Reaction Steps

A particularly preferred embodiment of synthesizing vitamin E from farnesol is illustrated in FIG. 3. Farnesol 3-8 is oxidized to farnesal 3-9 under Oppenauer oxidation conditionS using aluminum isopropoxide and acetone. Farnesal 3-9 is then converted to dehydrofarnesyl acetone 3-10 by an aldol condensation reaction with acetone. Reduction of olefin moieties on dehydrofarnesyl acetone 3-10 by hydrogenation then produces 6,10,14-trimethyl pentadecan-2-one 3-11. Addition of acetylide to the ketone 3-11 then generates propargylic alcohol 3-12 which is partially reduced using Lindlar hydrogenation condition to produce isophytol 3-13. Reaction of isophytol 3-13 with 2,3,5-trimethyl hydroquinone 3-5 in the presence of an acid catalyst then produces vitamin E.

Provenance & Evidence