Concurrent alkylation-methoxylation of 4,5-dihalopyridazin-6-ones and synthesis of 5-halo-4-hydroxypyridazin-6-ones

1-Alkyl-5-halo-4-methoxypyridazin-6-ones were synthesized from 1-alkyl-4,5-dihalopyridazin-6-ones by the concurrent alkylation-methoxylation. 1-Alkyl-5-halo-4-hydroxypyridazin-6-ones were also prepared.