Process for the preparation of {2-[4-(alpha-phenyl-p-chlorobenzyl)piperazin-1-yl]ethoxy} acetic acid and novel intermediates therefor
申请人:——
公开号:US20030092911A1
公开(公告)日:2003-05-15
The invention refers to a novel process for the preparation of cetirizine of formula (I) as well as to novel {2-[4-(&agr;-phenyl-p-chloro-benzyl)piperazin-1-yl]ethoxy}acetamides of formula II, wherein R
1
and R
2
represent, independently, a C
1-4
alkyl group optionally substituted by a phenyl group, a C
2-4
alkenyl group or a cyclohexyl group, or R
1
and R
2
form together with the adjacent nitrogen atom a morpholino group. According to the novel process, an acetamide of formula (II) is hydrolized, if desired in the presence of a phase transfer catalyst, to obtain cetirizine.
该发明涉及一种新型制备化学式(I)的右美沙芬的方法,以及一种新型化学式II的{2-[4-(&agr;-苯基-p-氯苄基)哌嗪-1-基]乙氧}乙酰胺,其中R1和R2分别独立表示C1-4烷基,可选择地被苯基取代,C2-4烯基或环己基,或者R1和R2与相邻的氮原子一起形成吗啡基团。根据这种新型方法,化学式(II)的乙酰胺在需要时在相转移催化剂的存在下水解,以获得右美沙芬。