| 摘要 |
The present invention relates to a process for the preparation of a compound of formula (I) said process comprising the steps of: a) reacting a compound of formula (II), with an acylating or a silylating agent to produce a compound of formula (III), wherein P1 and P2 are each independently a protecting group selected from R2−Si—R3R4, or R1CO—, wherein R1 is a group selected from C1-6alkyl or C3-6cycloalkyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; R2, R3 and R4 are each independently a group selected from C1-6alkyl or phenyl, each group being optionally substituted by one or more substituents independently selected from fluoro or C1-4alkyl; b) reacting the compound of formula (III) in the presence of palladium acetate or a derivative thereof to produce compound of formula (IV); and c) reacting the compound of formula (IV) with a reducing agent to produce compound of formula (I). |
