Synthesis Of Methyl Dihydrojasmonate

Methyl dihydrojasmonate is an important synthetic perfume product in fine chemicals. It could be synthesized by a key intermediate 2-pentylidene cyclopentanone formed a condensation starting from cyclopentanone and n-valeraldehyde, followed by isomerization, Michael addition and a selective decarboxylation. The related reaction conditions and factors such as catalysis of some catalysts etc were discussed. In the procedures, 2-pentylidene cyclopentanone intermediate, which could be isomerizated into a 2-pentyl cyclopentenone under acidic conditions, was effectively prepared in the presence of a phase transfer promotor. A Michael addition of dimethyl malonate and 2-pentyl-cyclopentenone could conduct a precursor which used for preparing aim compound by a selective decarboxylation. The total yield of methyl dihydrojasmonate could be improved 46.3% in some rational technological parameters. Some related reaction mechanisms, novel methodology and solvent-free Michael addition were also discussed. The structures and compositions of these compounds were accomplished by IR and GS-MS.