▎ 摘　　要

NOVELTY - Preparing β-apo-8'-carotene acid ethyl ester i.e. ethyl (2E,4E,6E,8E,10E,12E,14E,16E)-2,6,11,15-tetramethyl-17-(2,6,6-trimethylcyclohexen-1-yl)heptadeca-2,4,6,8,10,12,14,16-octaenoate (4), comprises adding decacarbon dialdehyde i.e. (2E,4E,6E)-2,7-dimethylocta-2,4,6-trienedial (1), C5 phosphine salt (2), C15 phosphine salt (3) and bimetallic supported catalyst into reaction flask under nitrogen atmosphere, and slowly adding alkali solution dropwise after a certain period of reaction to obtain final product. USE - The method is useful for preparing β-apo-8'-carotene acid ethyl ester i.e. ethyl (2E,4E,6E,8E,10E,12E,14E,16E)-2,6,11,15-tetramethyl-17-(2,6,6-trimethylcyclohexen-1-yl)heptadeca-2,4,6,8,10,12,14,16-octaenoate. ADVANTAGE - The method: solves the problem of harsh reaction conditions; solves the problem of low yield, solves the problem of complicated and difficult purification in the current technology; and provides an indirect and efficient method for the synthesis of product. DETAILED DESCRIPTION - Preparing β-apo-8'-carotene acid ethyl ester i.e. ethyl (2E,4E,6E,8E,10E,12E,14E,16E)-2,6,11,15-tetramethyl-17-(2,6,6-trimethylcyclohexen-1-yl)heptadeca-2,4,6,8,10,12,14,16-octaenoate of formula (4), comprises adding decacarbon dialdehyde i.e. (2E,4E,6E)-2,7-dimethylocta-2,4,6-trienedial of formula (1), C5 phosphine salt of formula (2), C15 phosphine salt of formula (3) and bimetallic supported catalyst into reaction flask under nitrogen atmosphere, and slowly adding alkali solution dropwise after a certain period of reaction to obtain final product. X and Y = Cl-or Br-.