| 摘要 |
The invention relates to a process for the preparation of spiro[cis-4-(beta-hydroxyethyloxy)cyclohexane-[3H]indol]-2'[1'H]-one derivatives of the formula (I) wherein R1 and R2 are as defined herein, by reduction of a dispiro[(1,3-dioxolane)-2,4'-cyclohexane-1'3'-[3H]indol]-2''[1''H]-one derivative of general formula (II), wherein R1 and R2 are as defined herein, which comprises carrying out the reduction (a) with sodium cyanoborohydride in the presence of a Lewis acid, or (b) with sodium borohydride in the presence of a strong acid. |
