Abstract: The present invention describes a novel synthetic method for preparing the key intermediate 2,6,10-trimethyl-1,1-dialkoxy-3,5,9-undecatriene of lycopene. An existing synthetic method have some disadvantages that it is very difficult to gain the raw material dialkyl 4-methyl-5,5-diakoxy-1-pentene-1-phosphonate (10) because no effective synthetic method can be adopted, and furthermore the obtained target compound is composed of several cis/trans isomers. This invention relates to a process comprising a condensation step wherein a starting C10-phosphonate is changed to its carbanion completely at a temperature of ?40˜30 under an atmosphere of a non-reactive gas in an organic solvent catalyzed by base, and then C4-dialkyl is added to undergo Wittig-Horner condensation. This invention affords all trans C14-acetal and this method is characterized with the advantages of simple procedure, easy access to raw material and low cost, which makes it has the value of industrial application.

Abstract: The invention relates to a novel important lycopene intermediate 3,7, 11-trimethyl-1,3,6,10-tetraene-dodecyl diethyl phosphonate. A current lycopene intermediate 2,4,6,10-tetra-double bond pentadec-carbon phosphonate is difficult to synthesize. The invention provides a novel intermediate, which has the following synthesis steps of: preparing 2,6,10-trimethyl-3,5,9-undecane triene-1-aldehyde from pseudoionone; preparing 2,6,10-trimethyl-2,5,9-undecane triene-1-aldehyde from the 2,6,10-trimethyl-3, 5,9-undecane triene-1-aldehyde; and subjecting the 2,6,10-trimethyl-2,5,9-undecane triene-1-aldehyde and tetraethyl methylenediphosphonate to condensation reaction to obtain target product. The invention can generate novel intermediate from raw material pseudoionone only by four reactions, thus the reactions are easy to control and great industrial value are achieved.

Abstract: The present invention describes a novel synthetic method for preparing the key intermediate 2,6,10-trimethyl-1,1-dialkoxy-3,5,9-undecatriene of lycopene. An existing synthetic method have some disadvantages that it is very difficult to gain the raw material dialkyl 4-methyl-5,5-diakoxy-1-pentene-1-phosphonate (10) because no effective synthetic method can be adopted, and furthermore the obtained target compound is composed of several cis/trans isomers. This invention relates to a process comprising a condensation step wherein a starting C10-phosphonate is changed to its carbanion completely at a temperature of ?40˜30 under an atmosphere of a non-reactive gas in an organic solvent catalyzed by base, and then C4-dialkyl is added to undergo Wittig-Horner condensation. This invention affords all trans C14-acetal and this method is characterized with the advantages of simple procedure, easy access to raw material and low cost, which makes it has the value of industrial application.