申请人:——
公开号:US20030109717A1
公开(公告)日:2003-06-12
A process for preparing compounds of the formula I
1
in which R
1
is hydrogen, an aliphatic group having 1-8 carbon atoms, C
1
-C
6
-alkoxycarbonyl, C
1
-C
6
-alkylthiocarbonyl or a cyclic ring system having 3-14 ring atoms, and
R
2
is hydrogen, an aliphatic group having 1-8 carbon atoms, or
R
1
and R
2
together with the carbon atom to which they are bound form a cyclic or bicyclic ring system having 3-14 ring atoms,
comprises the preparation of compounds of the formula II
2
in which R
3
and R
4
are readily detachable groups and R
1
and R
2
are as defined above, as starting materials or intermediates and the cyclization of these under suitable reaction conditions to give compounds of the formula I. The intermediates of the formula II are novel.
一种制备式 I 化合物的工艺
1
其中 R
1
是氢、具有 1-8 个碳原子的脂肪族基团、C
1
-C
6
-烷氧基羰基、C
1
-C
6
-烷基硫代羰基或具有 3-14 个环原子的环状系统,以及
R
2
是氢、具有 1-8 个碳原子的脂肪族基团,或
R
1
和 R
2
与它们所结合的碳原子一起形成具有 3-14 个环原子的环或双环系统、
包括制备式 II 的化合物
2
其中 R
3
和 R
4
为易分离基团,R
1
和 R
2
如上定义,作为起始原料或中间体,并在合适的反应条件下进行环化反应,得到式 I 的化合物。式 II 的中间体是新型的。