Abstract:Diethyl \[(1E,3E,5E)-2,6,10-trimethylundeca-1,3,5,9-tetraen-1-yl\]phosphonate (9) was synthesized via a condensation between tetraethyl methylenebis(phosphonate) (7) and 6,10-dimethyl-3,5,9-undecatrien-2-one(8) by Wittig-Horner reaction, (3E,5E,7E)-3,8-dimethyldeca-3,5,7-trienedial (5) was prepared from (E)-tetraethyl but-2-ene-1,4-diylbis-(phosphonate)(2) and 4,4-dimethoxy-2-butanone (3) by Wittig-Horner reaction followed by hydrogenation. Lycopene was synthesized from diethyl \[(1E,3E,5E)-2,6,10-trimethylundeca-1,3,5,9-tetraen-1-yl\]phosphonate(9)and(3E,5E,7E)-3,8-dimethyldeca-3,5,7-trienedial(5) by Wittig-Horner reaction,the structure of products was confirmed by NMR, HRMS/GC-MS and IR techniques. The total yield was 16.7%.