Patent ID: 7453001

Claim:
A process of producing an isoxazole derivative represented by the following formula (I): (wherein: R 1 represents a hydrogen atom, optionally substituted C 1 -C 20 hydrocarbon group, or —C(═O)OR 1a (wherein R 1a is an optionally substituted C 1 -C 10 alkyl group, optionally substituted C 2 -C 10 alkenyl group or optionally substituted C 2 -C 10 alkynyl group); R 2 and R 3 , which may be the same or different, each independently represents a hydrogen atom, halogen atom, hydroxy group, optionally substituted C 1 -C 20 alkyl group, or optionally substituted C 6 -C 20 aryl group; R 4 , which may be the same or different, each independently represents a hydrogen atom, halogen atom, hydroxy group, cyano group, nitro group, optionally substituted amino group, optionally substituted C 1 -C 20 hydrocarbon group, optionally substituted C 1 -C 10 alkoxy group, optionally substituted C 1 -C 10 acyl group or optionally substituted 5- to 7-membered heterocyclic group; R 5 represents a hydrogen atom, halogen atom, hydroxy group, optionally substituted C 1 -C 20 hydrocarbon group, optionally substituted C 1 -C 20 alkoxy group or optionally substituted 5- to 7-membered heterocyclic group; and, n represents 0, 1, 2, 3 or 4), which comprises reacting a compound represented by the following formula (II): (wherein R 1 , R 2 and R 3 are the same as stated above; Z represents —O − M + (wherein M represents Na, K or NEt 3 ), oxo or hydroxy group; and the dotted line represents a chemical bond when Z is —O − M + or hydroxy group) with a compound represented by the following formula (III): (wherein R 4 , R 5 and n are the same as stated above; and Y represents —CNO) in the absence of a solvent or in a solvent inert to the reaction.