申请人:Tian Guanghui
公开号:US20100048897A1
公开(公告)日:2010-02-25
The present invention discloses a process for preparing sildenafil and its intermediates having the structures outlined below:
In particular, the present invention provides a process for preparing the compound of formula (I) and its intermediates, i.e. the compounds of formula (I), (II), (III) and (IV). The compound of formula (I) is obtained from the compound of formula (II); the compound (II) is obtained from the compound of formula (III) and methylpiperazine; the compound (III) is obtained by treating the compound of formula (IV) with chlorosulfonic acid; the compound (IV) is obtained though treating the compound of formula (V) in the presence of at least one selected from POX
3
, PX
3
, PX
5
and their mixtures in any ratio. The process for preparing the compound of formula (I) according to the present invention reduces the side reactions in the processes of the prior art. These improvements lead to higher yields and a better industrial applicability with easier controlling of the reaction.
本发明公开了一种制备西地那非及其中间体的过程,具有下面概述的结构:特别地,本发明提供了一种制备化合物(I)及其中间体的过程,即化合物(I)、(II)、(III)和(IV)的化合物。化合物(I)是从化合物(II)获得的;化合物(II)是从化合物(III)和甲基哌嗪获得的;化合物(III)是通过用氯磺酸处理化合物(IV)获得的;化合物(IV)是通过在POX3、PX3、PX5及其混合物中至少选择一种存在的情况下处理化合物(V)获得的。根据本发明的制备化合物(I)的过程减少了先前技术中的副反应。这些改进导致更高的产量和更好的工业适用性,反应控制更容易。