申请人:Benkhoff Johannes
公开号:US20050222397A1
公开(公告)日:2005-10-06
The present invention relates to a process for the preparation of a compound of the general formula (1), which comprises converting a compound of the general formula (II), in an aprotic organic solvent in the presence of a catalytically active amount of a strong acid (catalyst) or of an agent that liberates a strong acid or of an ammonium salt of a strong acid, it also being possible for the catalyst to be part of the starting material/product, into a compound of formula I, wherein R
5
, R
6
and R
8
are each independently of the others a hydrogen atom, a nitro group, a sulfo group, a halogen atom, a pseudohalogen, a group COOR
1
or CONHR
2
or a C
1-8
alkyl, C
1-8
alkoxy or aryloxy radical, an amide group, a thioalkyl or thioaryl radical, an alkyl- or aryl-sulfonyl radical, an alkyl- or aryl-sulfinyl radical, a trifluoromethyl group or a phosphono group, R
1
and R
2
being a hydrogen atom or a C
1-8
alkyl radical or an aryl or aralkyl radical, R
10
is a group —C(O)CH
2
C(O)CH
3
and R
11
is a hydrogen atom or an acyl radical, or R
10
and R
11
are a group —C(O)CH
2
C(O)CH
3
. The process according to the invention is simple to perform and results in products of high chemical purity and high isomeric purity in a high yield.
本发明涉及一种通式(1)化合物的制备工艺,该工艺包括在有催化活性的强酸(催化剂)或释放出强酸的制剂或强酸的铵盐(催化剂也可以是起始原料/产物的一部分)存在的情况下,在非沸腾有机溶剂中将通式(II)化合物转化成式 I 的化合物,其中 R
5
, R
6
和 R
8
各自独立地为氢原子、硝基、磺基、卤素原子、假卤素、基团 COOR
1
或 CONHR
2
或 C
1-8
烷基,C
1-8
烷氧基或芳氧基、酰胺基、硫代烷基或硫代芳基、烷基或芳基磺酰基、 烷基或芳基亚磺酰基、三氟甲基或磷酰基,R
1
和 R
2
是氢原子或 C
1-8
烷基或芳基或芳烷基,R
10
是一个基团 -C(O)CH
2
C(O)CH
3
和 R
11
是氢原子或酰基,或 R
10
和 R
11
是一个基团 -C(O)CH
2
C(O)CH
3
.本发明的工艺操作简单,可生产出高化学纯度和高异构纯度的高产率产品。