| 摘要 |
The present invention relates to a process for preparing a compound of the general formula I, in which R represents an ethoxymethyl group or tert-butyldiphenylsilyl group, from a relevant aldehyde by reacting with tetrabromomethane in the presence of triphenylphosphine under the formation of dibromoolefin 12, wherein Ri1 denotes an ethoxymethyl or biphenyl carbonyl group. Dibromoolefin is then subjected to dehydrohalogenation to give a corresponding 1-bromalkyne, which further reacts with 3-cyclohexylpropane to give the compound of the general formula I. The preparation process uses mild reaction conditions, reduced number of synthetic steps and agents, which cannot cause racemization of the individual intermediates. The invention also relates to the use of the above-described preparation process for the preparation of alpha prostol. |
