| 摘要 |
<p>This invention relates to a process for converting 2,4-dichloropyridines into 2-aryloxy-4-chloropyridines, comprising reacting a compound of formula (I), wherein R1 is (C¿1?-C4)alkyl; R?2¿ is methyl or ethyl; and R?3, R4 and R5¿ are selected, independently, from (C¿1?-C4)alkyl and (C1-C4)alkoxy; or a pharmaceutically acceptable salt thereof; comprising reacting a compound of formula (II), wherein R?1 and R2¿ are defined as above, with a compound of formula (III), wherein R?3, R4 and R5¿ are defined as above, in the presence of a base that is capable of deprotonating the compound of formula (III), optionally in the presence of an organometallic halide or oxide and a suitable solvent, and then optionally converting the resulting compound of formula (I) into a pharmaceutically acceptable salt of such compound.</p> |
