申请人:——
公开号:US20040063957A1
公开(公告)日:2004-04-01
A process for preparing substituted pyridine N-oxide compounds of the formula
1
in which R1, R2, R3 and R4 are each H, a carboxyl group or a C
1
-C
12
-alkyl radical which may contain atoms from the group of N, O and S, or R1 and R2 and/or R3 and R4 together may each form an optionally substituted C
4
-C
20
-alkylene radical which may contain atoms from the group of N, O and S,
A is benzyl or a (CH
2
)
m
group where
m may be an integer from 1 to 12,
Z
1
and Z
2
are each independently O or S, and Y is H, a C
1
-C
12
-alkyl radical which may optionally contain atoms from the group of N, O and S, a C
6
-C
20
-aryl radical or a C
5
-C
20
-heterocycle, and the radicals may optionally be substituted,
or Z
2
and Y together form an optionally substituted ring or ring system, in which case the ring or ring system may contain atoms from the group of N, O and S, from the corresponding 4-halopyridine N-oxide of the formula
2
in which X is chlorine, bromine or iodine, by reacting the compound of the formula (II), in the presence of a phase transfer catalyst and of a base, with a compound of the formula
HZ
1
-A-Z
2
-Y (III)
in which Z
1
, Z
2
, A and Y are each as defined above, at a temperature up to the reflux temperature, to give the corresponding substituted pyridine N-oxide compound of the formula (I), and also a process for preparing the compound of the formula (II).
一种制备取代吡啶N-氧化物化合物的方法,该化合物的公式为1,其中R1、R2、R3和R4分别为H、羧基或可能含有N、O和S的C1-C12烷基基团,或者R1和R2和/或R3和R4可以共同形成一个可选取代的C4-C20烷基基团,该基团可能含有N、O和S的原子,A为苄基或(CH2)m基团,其中m可以是1到12的整数,Z1和Z2各自独立地为O或S,Y为H、C1-C12烷基基团,该基团可以选择地含有N、O和S的原子,C6-C20芳基基团或C5-C20杂环,且基团可以选择性地被取代,或者Z2和Y共同形成一个可选择性取代的环或环系统,此时该环或环系统可以含有N、O和S的原子,从公式2中相应的4-卤代吡啶N-氧化物开始,其中X为氯、溴或碘,通过在相转移催化剂和碱存在下,将公式(II)的化合物与公式HZ1-A-Z2-Y(III)的化合物在回流温度以下的温度下反应,从而得到公式(I)的相应取代吡啶N-氧化物化合物,以及制备公式(II)的化合物的方法。