Synthesis of citronellol from isoprene in three steps was reported. The reaction steps were consisted of three parts, i.e.
a) Dimerization of isoprene was carried out in the presence of tetraethoxy zirconium, diethylaluminium chloride and triphenylphosphine as a catalyst system to afford 2, 6-dimethyl-1, 3, 6-octatiene [II].
b) The triene [II] was converted into 2, 6-dimethyl-2, 6-octadiene [III] by selective 1, 4-hydrogenation of the conjugated diene moiety of [II] catalyzed by (methyl benzoate) chromiumtricarbonyl under hydrogene atmosphere.
c) Citronellol [IV] was obtained from [III] by use of hydrido bis (cyclopentadienyl) zirconium chloride (hydrozirconation reaction) and successive oxidation.
Especially, in this report, reaction conditions such as molar ratio of the zirconium hydride to [III], solvent and reaction temperature were discussed.
Total yield of citronellol base on [II] was ca. 50%.
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