Patent EA-002126-B1 (EA)
Title: New intermediates to pesticides
Inventor: PEVERE VIRGINIE
IPC: B01J31/04
Filed: 1997-02-04
Abstract: 1. A process for preparing a compound of formula (I)   wherein R is -CO2R<3>; R<1> is C1 -C6 alkyl or cycloalkyl having from three to seven ring carbon atoms, optionally substituted by C1 -C6 alkyl or halogen; Ar is: phenyl optionally substituted by one to five groups R<2> which may be the same or different; or is phenyl optionally substituted by from one to three groups R<2> which may be the same or different and wherein two additional substituents on adjacent positions of the phenyl ring, together with the two atoms to which they are attached, form a 5- to 7- membered ring which is optionally substituted by one or groups R<11> which may be the same or different; or is a group Het which is optionally substituted by one or more groups R<2>, wherein Het represents a first heterocyclic ring containing from one to four heteroatoms in the ring selected from oxygen, nitrogen and sulphur, which is optionally fused with a benzene, or carbocyclic or second heterocyclic ring (which is optionally saturated or partially saturated) to form a bicyclic system, wherein the first heterocyclic ring of the group Het is attached to the carbonyl group in the 4-position of the isoxazole ring; R<2> is halogen, C1 -C6 alkyl, C1 -C6 alkoxy, l C1 -C6 haloalkyl, C1 -C6 haloalkoxy, -S(O)mR<4>, (CR<5>R<6>)qS(O)mR<4>, nitro, cyano, -N(R<5>)SO2R<8>, -OSO2R<8>, cycloalkyl having from three to seven ring carbon atoms, straight- or branched- chain alkenyl or alkynyl having up to six carbon atoms, -CO2R<7>, -S(O)mR<9>, -O(CH2)r OR<8>, -NR<5>R<6>, -CONR<5>R<6>, -N(R<5>)C(=O)R<10>, -(CR<5>R<6>)qN(R<5>SO2R<8>, -(CR<5>R<6>)qN(R<5>)C(=)R<10>, (CR<5>R<6>)qP(=O)R<12>R<13>, -(CR<5>R<6>)qR<14>, -(CR<5>R<6>)qR<16> or a straight- or branched-chain alkyl containing up to six carbon atoms substituted by -OR<5>; where R<2> is present on a heterocyclic or carbocyclic ring of the group Het, R<2> may also represent =O, =S, cyclic ketal or cyclic thioketal; R<3> is C1 -C6 alkyl, C1 -C6 haloalkyl, aryl or benzyl; R<4> is C1 -C6 alkyl, or phenyl optionally substituted by from one to five groups selected from C1 -C6 alkyl, C1 -C6 haloalkyl, halogen and -S-alkyl; R<5> and R<6> independently are hydrogen, C1 -C6 alkyl or C1 -C6 haloalkyl; R<7> is hydrogen or C1 -C6 alkyl; R<8> is C1 -C6 alkyl or C1 -C6 haloalkyl; R<9> is C1 -C6 haloalkyl, C1 -C6 alkenyl or C1 -C6 haloalkenyl; R<10> is R<8>, C1 -C6 alkoxy or C1 -C6 alkylthio; R<11> is R<2> or =O, =S, C1 -C6 alkylimino, cyclic ketal or cyclic thioketal; R<12> and R<13> are C1 -C6 alkyl, hydroxy, C1 -C6 alkoxy or C1 -C6 haloalkoxy; R<14> is a 5-membered heteroaromatic ring of formula   in which D, E, G and J independently represent -CR<15>- or a nitrogen atom, with at least one of D, E, G and J representing -CR<15>; two adjacent groups D, E, G and J may together form a second phenyl or 5- to 7- membered heteroaromatic ring optionally substituted by one or more groups selected from halogen or C1 -C6 alkyl, in which the 5- to 7- membered heterocyclic ring contains from one to four heteroatoms in the ring which may be the same or different selected from nitrogen, oxygen and sulphur; R<15> is hydrogen, halogen, C1 -C6 alkyl, C1 -C6 haloalkyl, nitro, cyano, -CO2R<7>, -S(O)mR<8>, C1 -C6 alkoxy, C1 -C6 haloalkoxy or cyclopropyl; R<16> is phenyl optionally substituted by halogen, nitro, cyano, C1 -C6 alkyl, C1 -C6 alkoxy, C1 -C6 haloalkyl, C1 -C6 haloalkoxy, -S(O)mR<8>, -(CR<5>R<6>)S(O)mR<8>; m is zero, one or two; q is one or two; and r is one, two or three; characterized by the reaction of a compound of formula (II):   wherein R, R<1> and Ar are as defined above, with hydroxylamine or a salt thereof. 2. A process for preparing a compound of formula (Ia):   R is -CO2R<3>; R<1> is C1 -C6 alkyl or cycloalkyl having from three to seven ring carbon atoms, optionally substituted by C1 -C6 alkyl or halogen; R<2> is halogen, C1 -C6 alkyl, C1 -C6 alkoxy, C1 -C6 haloalkyl, C1 -C6 haloalkoxy, -S(O)mR<4>, -(CR<5>R<6>)qS(O)mR<4>, nitro, cyano, -N(R<7>)SO2R<8>, -OSO2R<8>, cycloalkyl having from three to seven ring carbon atoms; or straight- or branched- chain alkenyl or alkynyl having up to six carbon atoms; R<3> is C1 -C6 lower alkyl, C1 -C6 lower haloalkyl, aryl or benzyl; n is an integer from one to five; R<4> is C1 -C6 alkyl, or phenyl optionally substituted by from one to five groups selected from C1 -C6 alkyl, C1 -C6 haloalkyl, halogen and -S-alkyl; R<5> and R<6> independently are hydrogen, C1 -C6 alkyl or C1 -C6 haloalkyl; R<7> is hydrogen or C1 -C6 alkyl; R<8> is C1 -C6 alkyl or C1 -C6 haloalkyl; m is zero, one or two; and q is one or two; characetized by the reaction of a compound of formula (IIa):   wherein R, R<1>, R<2> and n are as defined above, with hydroxylamine or a salt thereof. 3. A process according to claim 1 or 2, characterized in that the reaction is performed at a temperature of from 20 degree C to the boiling point of the solvent, preferably from 30 to 80 degree C. 4. A process according to claim 1, 2 or 3, characterized in that the molar ratio of the compound of formula (II): hydroxylamine is generally from 1:1 to 1:2, preferably from 1:1.01 to 1:1.2. 5. A process according to any one of claims 1 to 4, characterized in that the reaction is performed in the presence of a base. 6. A compound of formula (II):   wherein R, R<1> and Ar are as defined in claim 1. 7. A compound of formula (IIa):   wherein R, R<1>, R<2> and n are as defined in claim 2. 8. A compound according to claim 6 or 7 in which R<1> is cycloalkyl having from three to seven ring carbon atoms, optionally substituted by C1 -C6 alkyl or halogen. 9. A compound according to claim 9 in which R<1> is 1-methylcyclopropyl or cyclopropyl. 10. The use of a compound of formula (II) as defined in claim 6 as an intermediate in the synthesis of a herbicide of formula (I) as defined in claim 1. 11. A process for the preparation of a compound of formula (II) as defined in claim 1, characterized by the reaction of a compound of formula (III):   wherein R<1> and Ar are as defined in claim 1, with a cyanoacetate of formula (IV): R<3>O C(=O)-CN (IV) wherein R<3> is as defined in claim 1, in the presence of a catalyst. 12. A process according to claim 11, characterized in that the catalyst is a transition metal catalyst, preferably a zinc or nickel catalyst; or an organic acid catalyst such as acetic acid or trifluoroacetic acid. 13. A process according to claim 11 or 12, characterized in that the reaction is performed at a temperature of from 20 degree C to the boiling point of the solvent, preferably from 50 to 90 degree C. 14. A process according to claim 10, 11 or 12, characterized in that the molar ratio of the compounds of formula (III): (IV) is from 1:1 to 1:2, preferably from 1:1.05 to 1:1.2.