PROCESS FOR THE PREPARATION OF PYRIDO [
2-1-A]
ISOQUINOLINE DERIVATIVES BY CATALYTIC ASYMMETRIC HYDROGENATION OF AN ENAMINE
申请人:Abrecht Stefan
公开号:US20080076925A1
公开(公告)日:2008-03-27
The invention relates to a process for the preparation of pyrido[2,1-
a
] isoquinoline derivatives of the formula
wherein R
2
, R
3
and R
4
are as defined in the specification, comprising the steps of a) catalytic asymmetric hydrogenation of an enamine of the formula
wherein R
1
is lower alkyl, in the presence of a transition metal catalyst containing a chiral diphosphane ligand, b) introduction of an amino protecting group Prot and c) amidation of the ester to form an amide of formula
wherein R
2
, R
3
, R
4
and Prot are as defined in the specification.
本发明涉及一种制备式为的吡啶并[2,1-a]异喹啉衍生物的方法,其中R2、R3和R4如规范中所定义,包括以下步骤:a)在手性二膦配体存在下,对式为的烯胺进行催化不对称氢化,其中R1为低碳基;b)引入氨基保护基Prot;c)酰胺化酯,形成式为的酰胺,其中R2、R3、R4和Prot如规范中所定义。