Abstract Methyl 3-oxo-8-phenoxy-6-octenoate (1) was cyclized using Pd (OAc) 2-PPh 3 as a catalyst to give 2-carbomethoxy-3-vinylcyclopentanone (2) and 2-carbomethoxy-4- cycloheptenone (3). The former was the main product in acetonitrile. 2-Alkylated 3-oxo-8- phenoxy-6-octenoates were converted mainly to the five-membered ketones. Based on this cyclization method, methyl dihydrojasmonate (8) was prepared from methyl 2-pentyl-3-oxo ...