Patent EA-002086-B1 (EA)
Title: Process for preparing 3,4,5-three-substituted 1-arylpyrazole
Inventor: NEWSOME PETER WYATT
IPC: C07D405/06
Filed: 1998-03-05
Abstract: 1. A process for preparing a compound having the formula:   wherein: Ar is optionally substituted phenyl or optionally substituted pyridyl; R3 is --C(O)R8OR -CN; R4 is S(O)mR8 wherein R8 is C1 C6 alkyl, C1 C6 haloalkyl or R9 m is 0, 1 or 2; R6 is --NH2, --OH or --CH3 ; R8 is C1 -C6 alkyl, C1 -C6 haloalkyl, R9 or Het; Het is a 5- or 6-membered heterocyclic ring, said ring having from one to three ring heteroatoms which are the same or different selected from the group consisting of nitrogen, sulfur and oxygen, each carbon atom of said ring being unsubstituted or being substituted by halogen, C1 -C6 alkyl, C1 -C6 haloalkyl, C1 -C6 alkoxy, C1 -C6 haloalkoxy, cyano, nitro amino, N-(C1 -C6 alkyl)amino, N,N-di(C1 -C6 alkyl)amino, OH, --S(O)m (C1 -C6 alkyl) or --S(O)m (C1 -C6 haloalkyl); and R9 is phenyl optionally substituted by one or more members selected from the group consisting of halogen, C1 -C6 alkyl, C1 -C6 haloalkyl, C1 -C6 alkoxy, C1 -C6 haloalkoxy, cyano, nitro, amino, N-(C1 -C6 alkyl)amino, N,N-di(C1 -C6 alkyl)amino, --OH, --S(O)m (C1 -C6 alkyl) and --S(O)m (C1 -C6 haloalkyl); said process comprising: (a) reacting a compound having the formula: Ar-N [triple bond] N<+>X<->               (I) wherein Ar is as defined above and X<-> is a compatible anion, with a compound having the formula:   wherein R3 and R4 are as defined above and R5 is --CN, --C(O)OR8 or --C(O)(C1 -C6 alkyl), to afford the corresponding compound having the formula:   wherein R3, R4, R5 and Ar are as defined above; and (b) subjecting the compound of formula (III) thus obtained to rearrangement in a protic or aprotic solvent, in the presence of base, to afford the corresponding compound of formula (IV), wherein the molar ratio of (I):(II) is from about 1:1 to about 1:2. 2. A process according to Claim 1, wherein Ar is phenyl having from 0 to 5 substituents or pyridyl having from 0 or 4 substituents, each substituent when present being selected from the group consisting of halogen, CN, NO2, C1 -C6 haloalkyl, C1 -C6 haloalkoxy, S(O)mCF3, SF5 and R10 ; and R10 is phenyl optionally having from one to five substituents selected from the group consisting of halogen, C1 -C6 alkyl, C1 -C6 haloalkyl, cyano(C1 -C6 alkyl), cyano, nitro, amino, hydrazino, C1 -C6 alkoxy, C1 -C6 haloalkoxy, (C1 -C6 haloalkyl)carbonyl, formyl, (C1 -C6 alkyl)carbonyl, thiocarbamoyl, carbamoyl, (C1 -C6 alkoxy)carbonyl, SF5 and R8 S(O)m, two adjacent phenyl substituents being optionally joined together to form a 1,3-butadienylene, methylenedioxy or halomethylenedioxy group. 3. A process according to Claim 1 or 2 wherein Ar has the formula:   wherein: Z is a trivalent nitrogen atom or a C--R7 radical, the other three valences of the carbon atom forming part of the aromatic ring; R1 and R7 are, independently of each other, hydrogen, halogen, CN or NO2; and R2 is halogen, C1 -C6 haloalkyl, C1 -C6 haloalkoxy, S(O)m CF3, SF5 or R10. 4. A compound which is 3-(4-chlorophenylsulfonyl)- 3-(2,6-dichloro-4-trifluoromethylphenylazo)-4-cyanobutan-2-one or 2-(4-chlorophenylsulfonyl)-2-(2,6-dichloro-4-trifluoromethyl) phenylazosuccinonitrile.