申请人:Boehringer Ingelheim Chemicals, Inc.
公开号:US06399828B1
公开(公告)日:2002-06-04
A process for making compound of formula I
from a phenylpropanolamine salt of formula II
wherein:
R1 is hydrogen or a lower alkyl group;
each R2 is independently a hydrogen, halogen, lower alkyl group, lower alkoxy groups, lower alkyl group substituted with 1 to 5 halogens, lower alkoxy groups substituted with 1 to 5 halogens, or both R2 together when on adjacent carbons constitute a —O(CH2)xO— where x is 1 to 4, thereby forming a ring structure fused with the phenyl group;
R3 is a C1-C8-alkyl group, a C1-C12-aralkyl group, C1-C12-alkaryl group, or a phenyl group, each optionally substituted by 1 to 5 substituents selected from halogen, hydroxy, or C1-C6-alkyl; and
HX is an equivalent of an organic or inorganic acid,
the process comprising:
(a) acylating the phenylpropanolamine salt of formula II with an acylating agent in a solvent at elevated temperature to make a reaction mixture containing an O-acylated phenylpropanolamine salt of formula III which can be isolated by the addition of a crystallization solvent, or optionally this mixture can be used in the next step; and
(b) hydrogenating the O-acylated phenylpropanolamine salt to make the compound of formula I in the presence of a catalyst.
从公式II的苯丙醇胺盐制备公式I化合物的过程,其中:R1为氢或低碳基团;每个R2独立地是氢、卤素、低碳基团、低烷氧基团、取代有1至5个卤素的低碳基团、取代有1至5个卤素的低烷氧基团,或当相邻碳上的两个R2在一起时,构成—O(CH2)xO—,其中x为1至4,从而形成与苯基融合的环结构;R3为C1-C8烷基、C1-C12-芳基烷基、C1-C12-烷基芳基或苯基,每个可以选择地取代为1至5个卤素、羟基或C1-C6烷基取代基;HX为有机或无机酸当量,该过程包括:(a)在溶剂中高温下用酰化剂酰化公式II的苯丙醇胺盐,制备含有O-酰化的公式III的反应混合物,可以通过加入结晶溶剂来分离,或者可选择将此混合物用于下一步;(b)在催化剂存在下,氢化O-酰化的苯丙醇胺盐,制备公式I的化合物。