Method for producing pest control agent
View Patent ↗To supply a derivative having a 2-acyliminopyridine structure and being represented by the following formula (I) in an amount required as a pest control agent stably and at a low cost, provided is a method comprising the steps of: acylating an amino group at position 2 of a compound represented by formula (A) by use of an acylating agent, to thereby produce a compound represented by formula (B); and further alkylating a nitrogen atom at position 1 of the compound represented by formula (B): [where Ar represents a phenyl group or a 5-to 6-membered heterocycle, R 1 represents a C 1-6 alkyl group, and Y represents a hydrogen atom; a halogen atom; a hydroxyl group; a C 1-6 alkyl group which may be substituted with a halogen atom; a C 1-6 alkyloxy group which may be substituted with a halogen atom; a cyano group; a formyl group; or a nitro group].
1. A method for producing a compound represented by the following formula (I):
[where Ar represents a phenyl group which may be substituted with one or more of halogen atom, an alkyl group or haloalkyl group, or a 5-to 6-membered heterocycle which may be substituted with one or more of a halogen atom, an alkyl group or haloalkyl group, R 1 represents a C 1-6 alkyl group which is substituted with one or more of a halogen atom, and Y represents a hydrogen atom; a halogen atom; a hydroxyl group; a C 1-6 alkyl group which may be substituted with a halogen atom; a C 1-6 alkyloxy group which may be substituted with a halogen atom; a cyano group; a formyl group; or a nitro group],
the method comprising, as shown in the following reaction formula:
the steps of:
acylating an amino group at position 2 of a compound represented by formula (A) (Y has the same meaning as that described above) by use of an acylating agent represented by R 1 COR 2 (where R 1 has the same meaning as that described above, and R 2 represents (1) a trifluoroacetoxy group, (2) a C 1-6 alkyloxy group which may be substituted with a halogen atom or a benzyloxy group whose phenyl group may be substituted with a halogen atom, a methyl group, a cyano group, a nitro group, or a methoxy group, (3) a C 1-6 alkylcarbonyloxy group which may be substituted with a halogen atom (provided that a trifluoroacetoxy group is excluded) or a phenylcarbonyloxy group whose phenyl group may be substituted with a halogen atom, a methyl group, a cyano group, a nitro group, or a methoxy group, (4) a hydroxyl group, or (5) a halogen atom) to thereby produce a compound represented by formula (B); and
further alkylating a nitrogen atom at position 1 of the compound represented by formula (B) by use of Ar—CH 2 —R 4 (where Ar has the same meaning as that described above, and R 4 represents a halogen atom, a C 1-6 alkylsulfoxy group which may be substituted with a halogen atom, or a phenylsulfoxy group which may be substituted with a halogen atom or a methyl group),
wherein the acylation is carried out in the absence of a base.
2. The method according to claim 1 , wherein
Ar is a 6-chloro-3-pyridyl group, and
Y is a hydrogen atom.
3. The method according to claim 1 , wherein
R 1 is a trifluoromethyl group.
4. The method according to claim 1 , wherein
R 1 is a trifluoromethyl group, and
R 2 is a trifluoroacetoxy group, an ethoxy group, a hydroxyl group, or a chlorine atom.
5. The method according to claim 1 , wherein
R 1 COR 2 is at least one acylating agent selected from the group consisting of trifluoroacetic anhydride, trifluoroacetic acid, ethyl trifluoroacetate, trifluoroacetyl chloride, and mixed acid anhydrides.
6. The method according to claim 1 , wherein
R 1 COR 2 is trifluoroacetic anhydride.
7. The method according to claim 1 , wherein
R 1 COR 2 is ethyl trifluoroacetate.
8. The method according to claim 1 , wherein
R 1 COR 2 is trifluoroacetyl chloride.
9. The method according to claim 1 , wherein
R 1 COR 2 is trifluoroacetic acid.