Bromination of acrylate derivative (I) by means of NBS and AIBN in CCl4 affords (II), which is then converted into (III) by reaction with trimethyl phosphite (A) in toluene. Wittig oxopropenylation of aldehyde (IV) with phosphonium bromide derivative (V) and NaOMe or NaOEt in DMF provides benzaldehyde derivative (VI), which finally reacts with phosphonate (III) and NaH by a Wittig-Horner reaction in THF.