Process for production of pyrazole-fused ring derivatives

A method for preparing a compound (II) represented by following formula:

• (wherein Z1 and Z2 each independently represents a methine group or a nitrogen atom;
• R5 represents a hydrogen atom or a C1-6 alkyl group;
• R1 represents a group represented by the formula —R10—R11 (wherein R10 represents a single bond, an oxygen atom or a sulfur atom;
• R11 represents a methyl group or an ethyl group) or a methoxymethyl group;
• R2 and R3 each independently represents a hydrogen atom, a t-butoxycarbonyl group or a group represented by the formula —X21—X31 (wherein X21 represents a methylene group or a carbonyl group;
• X31 represents a C1-6 alkyl group, a C3-8 cycloalkyl group, a tetrahydropyran-yl group or a tetrahydrofuran-yl group)) or a salt thereof, or a solvate thereof:
• comprising the steps of:
• reacting a compound (I) represented by following formula:
• (wherein Z1, Z2, R1, R2, R3 and R5 have the same definitions as described above for Z1, Z2, R1, R2, R3 and R5, respectively) with an organometallic reagent, and
• thereafter reacting the resulting product with pentafluoroiodobenzene, to produce the compound (II) or a salt thereof, or a solvate thereof.