Production method of pyridazinone compounds
The present invention provides an industrially advantageous method of producing a pyridazinone compound. The present invention relates to the following method of producing a pyridazinone compound: Formula (II), (IIIa), (IV) or (IV″), Formula (IIIb), (Vb) or (V″b), Formula (VI), (I) or (I″), wherein each symbol is as described in the specification.
1. A method of producing a compound represented by the formula (I) or formula (I′):
wherein
R 1 is
(i) a C 6-14 aryl group,
(ii) —OR 8 wherein R 8 is a C 1-10 alkyl group or a C 6-14 aryl group, or
(iii) —SR 8 wherein R 8 is a C 6-14 aryl group,
R 2 is a hydrogen atom or a C 1-6 alkyl group,
Ring A is benzene substituted by 5- or 6-membered monocyclic aromatic heterocyclic group(s), and optionally further optionally substituted by 1 to 5 halogen atoms, and
R 7 is phenyl,
or a mixture thereof or a salt thereof, which comprises
step (1): a step of reacting a compound represented by the formula (II):
wherein each symbol is as defined above,
or a salt thereof, with a compound represented by the formula (Ma):
wherein
R 3a , R 4a , R 5a and R 6a are each independently a C 1-6 alkyl group,
or a salt thereof, to give a compound represented by the formula (IV) or formula (IV′):
wherein each symbol is as defined above,
or a mixture thereof or a salt thereof;
step (2): a step of reacting the compound represented by the formula (IV) or formula (IV′) or a mixture thereof or a salt thereof with a compound represented by the formula (IIIb):
wherein
R 3b , R 4b , R 5b and R 6b are each independently a C 1-6 alkyl group,
or a salt thereof, to give a compound represented by the formula (Vb) or formula (V′b):
wherein each symbol is as defined above,
or a mixture thereof or a salt thereof; and
step (3): a step of reacting the compound represented by formula (Vb) or formula (V′b) or a mixture thereof or a salt thereof, with a compound represented by the formula (VI):
R 7 NH—NH 2 (VI)
wherein each symbol is as defined above,
or a salt thereof.
2. The method of claim 1 , wherein the compound represented by the obtained formula (IV) or formula (IV′) or a mixture thereof or a salt thereof obtained in step (1) is subjected to step (2) without isolation.
3. The method of claim 1 , wherein R 1 is methoxy, and R 2 is a hydrogen atom.
4. The method of claim 1 , wherein Ring A is 4-(pyrazol-1-yl)-2-fluorobenzene, and R 7 is phenyl.
5. The method of claim 1 , wherein R 1 is methoxy, R 2 is a hydrogen atom, Ring A is 4-(pyrazol-1-yl)-2-fluorobenzene, and R 7 is phenyl.