Process for preparing a 2-halo-3-nitro-4-aminopyridine compound

摘要

A process for preparing a 2-halo-3-nitro-4-aminopyridine compound of formula (I) by reacting a compound of formula (IV) with an amine of formula H2N-X-(Y)a-Z. All variables are defined as follows: X is alkylene, cycloalkylene or cycloalkenylene; X2 is Cl or F; Y is NR4, O or S; a is 0 or 1; Z is represented by formula (II) or formula (III), where Z1 is N, CR5, (CH)m-CR5 or (CH2)m-N (m being 1 or 2) and Z2 is N, NR6, O or S (n being 0 or 1) and Ra and Rb are independently H, OH, alkyl, hydroxyalkyl, alkylmercaptyl, thioalkyl, alkoxy, alkoxyalkyl, amino, alkylamino, carboxyl, acyl, halogen, carbamoyl, alkylcarbamoyl, aryl or heterocyclyl; R4, R5 and R6 are independently H, alkyl, aryl or heterocycyl; X1 is F