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的苯丙醇胺盐中制备公式I的化合物的过程,其中:R1是氢或较低的烷基基团;每个R2独立地是氢、卤素、较低的烷基基团、较低的烷氧基团、1至5个卤素取代的较低烷基基团、1至5个卤素取代的较低烷氧基团,或当两个R2在相邻碳上时一起构成一个—O(CH2)xO—的环结构,其中x为1至4,从而形成与苯基融合的环结构;R3是C1-C8-烷基基团、C1-C12-芳基烷基基团、C1-C12-烷基芳基基团或苯基,每个基团可选择地被1至5个卤素、羟基或C1-C6-烷基取代;HX是有机或无机酸的当量,该过程包括:(a)在溶剂中使用酰化剂对公式II的苯丙醇胺盐进行酰化反应,以制备含有O-酰化苯丙醇胺盐的反应混合物,在升高的温度下,该O-酰化苯丙醇胺盐可以通过结晶溶剂的加入而分离,或者可选地,该混合物可用于下一步骤;和(b)在催化剂存在下,对O-酰化苯丙醇胺盐进行加氢反应,制备公式I的化合物。