Abstract:Lycopene(Ⅵ) was synthesized via α,β-unsaturated aldehyde with α-tertiary center strategy. Firstly, Pseudoionone(Ⅰ), an inexpensive raw material, was adopted to synthesize 2, 6, 10-trimethylundeca-3, 5, 9-trienal (Ⅱ). Then the key intermediate, diethyl (3, 7, 11-trimethyldodeca-1, 4, 6, 10-tetraenyl) phosphonate(Ⅳ), was formed by Wittig-Horne reaction of the aldehyde II and tetraethyl methylenebis-phosphonate(Ⅲ). The final product, all-E lycopene, can be collected after Wittig-Horner reaction and isomers rearrangement of compound Ⅳ and 2, 7-dimethylocta-2, 4, 6-triene-1, 8-dial(Ⅴ). The synthesis of lycopene needed only 3 steps, with the yield of 37.0%. The structure of all-E lycopene was characterized by IR, HRMS and NMR techniques.