Patent ID: 7067655

Claim:
A process of preparing a compound of formula II wherein R is R 1 -furanyl, R 1 -thienyl, R 1 -pyridyl, R 1 -pyridyl N-oxide, R 1 -oxazolyl, R 10 -phenyl, R 1 -pyrrolyl or C 4 –C 6 cycloalkenyl; R 1 is 1 to 3 substituents independently selected from hydrogen, C 1 –C 6 -alkyl, —CF 3 , halogen, —NO 2 , NR 12 R 13 , C 1 –C 6 alkoxy, C 1 –C 6 alkylthio, C 1 –C 6 alkylsulfinyl, and C 1 –C 6 alkylsulfonyl; R 10 is 1 to 5 substituents independently selected from the group consisting of hydrogen, halogen, C 1 –C 6 alkyl, hydroxy, C 1 –C 6 alkoxy, —CN, —NH 2 , C 1 –C 6 alkylamino, di-((C 1 –C 6 )alkyl)amino, —CF 3 , —OCF 3 and —S(O) 0-2 (C 1 –C 6 )alkyl; R 12 is H or C 1 –C 6 alkyl; and R 13 is (C 1 –C 6 )alkyl-C(O)— or (C 1 –C 6 )alkyl-SO 2 —; comprising (1) treating 2-amino-4,6-dihydroxypyrimidine with POCl 3 in dimethylformamide to obtain 2-amino-4,6-dichloropyrimidine-5-carboxaldehyde (2) treating carboxaldehyde VII with a hydrazide of the formula H 2 N—NH—C(O)—R, wherein R is as defined above, to obtain (3) treating the intermediate of formula VIII with hydrazine hydrate to form a pyrazolo ring, thus obtaining the intermediate of formula IX (4) forming the desired compound of formula II by dehydrative rearrangement.