The Total Synthesis Of ?-carotene

?-carotene as an antioxidant is a kind of the natural carotenoids.It can counteract peroxide radicals,play an important role in anti-aging,but also to maintain and promote the immune function.Because of its above function,?-carotene is one of the research hotspots.A new synthetic route of ?-carotene was designed and successfully developed in this paper.(1)With C4 phosphonate and ?-Cyclociral as starting materials,according to Wittig-Horner condensation first synthesised C14 enol,and the yield was 68.3%,the purity was 97.6%,then hydrolyzed to get the intermediate C14 aldehyde,the yield was 71.7%,the purity was 98.1%.C14 enol as a new compound had been applied for a Chinese invention patent(CN104418713A).(2)C15 phosphonate can be obtained via Wittig-Horner condensation with C14 aldehydel and Methylenebisphosphonic acid tetraethyl ester as starting materials,the yield was 90.1%,the purity was 94.3%.The synthetic route of C15 phosphonate had been applied for a Chinese invention patent(CN104418885A).(3)?-carotene can be obtained via Wittig-Horner condensation with C15 phosphonate and C10 Trienedial as starting materials,the yield was 74.5%,the purity was 96.8%.The synthetic route of ?-carotene had been applied for a Chinese invention patent(CN104418885A).There is also an article about its synthetic route.The intermediates and products were identified by IR,MS,1H-NMR,13C-NMR.The route mainly used Wittig-Horner condensation reaction,only for four steps,with simple operation,cheap raw materials,mild conditions,and less side effects.This is a great significance to the industrial production of ?-carotene.