| 主权项 |
1. A process for the preparation of a compound of formula (I) wherein R, R1 and R2, simultaneously or independently, represent a hydrogen atom or a linear or branched C1-5 alkyl group; R3 represents a linear or branched C1-5 alkyl or alkenyl group; or R1 and R3, taken together, represent a C2-9 alkanediyl or alkenediyl group optionally substituted by one to two linear or branched C1-5 alkyl groups;by the isomerisation of the corresponding compound of the formula (II) wherein R, R1, R2 and R3 have the same meaning as in formula (I);said isomerisation being performed in the presence of a catalyst system comprisingi) metal selected amongst palladium (Pd) or platinum (Pt);ii) molecular hydrogen or a hydrogen source. |
