(19) TZZ¥_¥¥_T (11) EP 3 159 339 A1 (12) EUROPEAN PATENT APPLICATION published in accordance with Art. 153(4) EPC (43) Date of publication: (51) Int Cl.: 26.04.2017 Bulletin 2017/17 C07D 413/04 (2006.01) C07D 471/04 (2006.01) A01N 43/76 (2006.01) A01N 43/90 (2006.01) (21) Application number: 15806287.7 (86) International application number: (22) Date of filing: 29.05.2015 PCT/JP2015/065512 (87) International publication number: WO 2015/190316 (17.12.2015 Gazette 2015/50) (84) Designated Contracting States: (72) Inventors: AL AT BE BG CH CY CZ DE DK EE ES FI FR GB • WAKAMATSU, Takayuki GR HR HU IE IS IT LI LT LU LV MC MK MT NL NO Oita-shi PL PT RO RS SE SI SK SM TR Oita 870-0106 (JP) Designated Extension States: • KASAI, Rika BA ME Osaka-shi Designated Validation States: Osaka 554-8558 (JP) MA (74) Representative: Vossius & Partner (30) Priority: 09.06.2014 JP 2014118457 Patentanwälte Rechtsanwälte mbB Siebertstrasse 3 (71) Applicant: Sumitomo Chemical Company, Limited 81675 München (DE) Tokyo 104-8260 (JP) (54) METHOD FOR PRODUCING PYRIDINE COMPOUND (57) To make it possible to produce a pyridine compound represented by formula (1) that is useful as an insecticide by reacting a compound represented by formula. (2) and a compound represented by formula (3). (In the formula, 1L represents a halogen atom; R2, R3, R4, R5, and R6 represent chain hydrocarbon groups, etc., having 1-6 carbon atoms optionally substituted by fluorine atoms. A 1 represents-NR7-, an oxygen atom, or a sulfur atom; A 2 represents a nitrogen atom or =CR8-. R7 and R8 represent C1-6 chain hydrocarbon groups or hydrogen atoms. M + represents a sodium ion, a potassium ion, or a lithium ion.) EP 3 159 339 A1 Printed by Jouve, 75001 PARIS (FR) (Cont. next page) EP 3 159 339 A1 2 EP 3 159 339 A1 Description TECHNICAL FIELD 5 [0001] The present invention relates to a method for preparing a pyridine compound. BACKGROUND ART [0002] WO 2013/018928 discloses a pyridine compound such as 2-(3-ethylsulfonyl-5-pentafluoroethylpyridin-2-yl)-3- 10 methyl-6-trifluoromethyl-3H-imidazo[4,5-b]pyridine represented by the following formula: 15 20 wherein A10 represents -NR27-, an oxygen atom, or a sulfur atom, 25 A20 represents a nitrogen atom or =CR 28-, A30 represents a nitrogen atom or =CR 29-, R21 represents a chain hydrocarbon group with one to six carbons which may optionally have substituent(s) or an alicyclic hydrocarbon group with three to six carbons which may optionally have substituent(s), R22, R23, and R24 represent each independently a chain hydrocarbon group with one to six carbons which may 30 optionally have substituent(s), a phenyl group which may optionally have substituent(s), a 5- or 6-membered hete- 30 30 30 40 30 40 rocyclic group which may optionally have substituent(s), , -OR-S(O)mR , -S(O)2NR R , -NR R , 30 40 30 40 30 30 30 40 -NR CO2R , NR C(O)R , -CO2R , -C(O)R , -C(O)NR R , -SF5, a cyano group, a nitro group, a halogen atom, or a hydrogen atom, R25 and R26 represent each independently a chain hydrocarbon group with one to six carbons which may optionally have substituent(s), a phenyl group which may optionally have substituent(s), a 5- or 35 30 30 30 40 6-membered heterocyclic group which may optionally have substituent(s), -OR, -S(O)mR , -S(O)2NR R , 30 40 30 40 30 40 30 30 30 40 -NR R , -NR CO2R ,-NR C(O)R , -CO2R , -C(O)R , -C(O)NR R , -SF5, a cyano group, a nitro group, a halogen atom, or a hydrogen atom, provided that both R 25 and R26 are not a hydrogen atom, m is an integer of 0-2, n is an integer of 0-2, 40 R30 and R40 represent each independently a chain hydrocarbon group with one to six carbons which may optionally have substituent(s), a phenyl group which may optionally have substituent(s), or a hydrogen atom, 27 30 R represents a chain hydrocarbon group with one to six carbons which may optionally have substituent(s),-CO 2R , -C(O)R30, an alicyclic hydrocarbon group with three to six carbons which may optionally have substituent(s), or a hydrogen atom, and 45 R28 and R29 represent each independently a chain hydrocarbon group with one to six carbons which may optionally 30 30 30 40 30 30 have halogen atom(s), -OR , -S(O)mR , -NR R ,-CO2R , -C(O)R , a cyano group, a nitro group, a halogen atom, or a hydrogen atom, which is useful as an insecticide. 50 [0003] WO 2013/018928 discloses a process for preparing 2-(3-ethylsulfonyl-5-pentafluoroethylpyridin-2-yl)-3-methyl- 6-trifluoromethyl-3H-imidazo[4,5-b]pyridine, which comprises oxidizing 2-(3-ethylsulfanyl-5-pentafluoroethylpyridin-2- yl)-3-methyl-6-trifluoromethyl-3H-imidazo[4,5-b]pyridine with m-chloroperoxybenzoic acid. SUMMARY OF THE INVENTION 55 [0004] The present invention is to provide a novel method for preparing the pyridine compound described above and includes the following inventions. 3 EP 3 159 339 A1 [1] A method for preparing a pyridine compound of formula (1) : 5 10 which comprises reacting a compound of formula (2): 15 20 wherein 25 L1 represents a halogen atom, R2, R3, R4, R5, and R6 represent each independently a chain hydrocarbon group having one to six carbons which may be optionally substituted with fluorine atom(s), a phenyl group which may optionally have substitu- 10 10 11 12 10 13 11 13 11 12 10 11 ent(s), -OR ,-S(O)mR , -S(O)2NR R , -NR R , -NR CO2R , -NR C(O)R ,-CO2R , -C(O)R , 11 12 -C(O)NR R , -SF5, a cyano group, a nitro group, or a hydrogen atom, 30 m and n are each independently an integer of 0-2, provided that both R5 and R6 are not a hydrogen atom, R10 and R13 represent each independently a chain hydrocarbon group having one to six carbons which may be optionally substituted with fluorine atom(s) or a phenyl group which may optionally have substituent(s), R11 and R12 represent each independently a chain hydrocarbon group having one to six carbons which may 35 be optionally substituted with fluorine atom(s), a phenyl group which may optionally have substituent(s), or a hydrogen atom, A1 represents -NR7-, an oxygen atom, or a sulfur atom, A2 represents a nitrogen atom or =CR8-, and R7 and R8 represent each independently a chain hydrocarbon group having one to six carbons, or a hydrogen 40 atom, wherein in the phenyl group which may optionally have substituent(s) as R 2, R3, R4, R5, R6, R10, R11, R12, and R13,the substituent(s) is/are one or moresubstituent(s) selected from the group consistingof a chain hydrocarbon group having one to six carbons which may be optionally substituted with fluorine atom(s), an alkoxy group having one to six carbons which may be optionally substituted with fluorine atom(s), an alkylthio group having 45 one to six carbons which may be optionally substituted with fluorine atom(s), an alkylsulfinyl group having one to six carbons which may be optionally substituted with fluorine atom(s), an alkylsulfonyl group having one to six carbons which may be optionally substituted with fluorine atom(s), an alkylcarbonyl group having two to six carbons which may be optionally substituted with fluorine atom(s), an alkoxycarbonyl group having two to six carbons which may be optionally substituted with fluorine atom(s), a halogen atom, a cyano group, and a nitro 50 group, with a compound of formula (3): 55 4 EP 3 159 339 A1 wherein R1 represents a chain hydrocarbon group having one to six carbons which may be optionally substituted with fluorine atom(s) or an alicyclic hydrocarbon group having three to six carbons which may be optionally substituted 5 with fluorine atom(s), and M+ represents a sodium ion, a potassium ion, or a lithium ion, to prepare the compound of formula (1), wherein R1, R2, R3, R4, R5, R6, A1, A2, and A3 have the same meanings as defined above. 10 [2] The method described in [1], wherein R 2 and R4 represent a hydrogen atom, R3 represents a hydrogen atom or a trifluoromethyl group, R5 represents a trifluoromethyl group, a tetrafluoroethyl group, a trifluoromethylthio group, a trifluoromethylsulfinyl group, or a trifluoromethylsulfonyl group, R 6 represents a hydrogen group, and A 2 represents a nitrogen atom or =CH-. [3] The method described in [2], wherein A 1 represents an oxygen atom, and A 2 represents =CH-. 15 [4] The method described in [2], wherein A1 represents-NR7-, R7 represents a methyl group, and A2 represents a nitrogen atom. [5] The method described in [3], wherein R 1 represents a chain hydrocarbon group having one to six carbons. [6] The method described in [4], wherein R 1 represents a chain hydrocarbon group having one to six carbons. [7] The method described in any one of [1] to [6], wherein L 1 represents a fluorine atom or a chlorine atom. 20 EMBODIMENT FOR CARRYING OUT THE INVENTION [0005] Examples of the halogen atom defined as L1 include a fluorine atom, a chlorine atom, a bromine atom, or an iodine atom. Examples of a preferable halogen atom as L 1 include a fluorine atom or a chlorine atom. 25 [0006] Examples of the chain hydrocarbon group having one to six carbons which may be optionally substituted with fluorine atom(s) defined as R 1, R2, R3, R4, R5, R6, R10, R11, R12, and R 13 include an alkyl group having one to six carbons which may be optionally substituted with fluorine atom(s), an alkenyl group having two to six carbons which may be optionally substituted with fluorine atom(s), and an alkynyl group having two to six carbons which may be optionally substituted with fluorine atom(s).