PROCESS FOR THE PREPARATION OF PYRAZOLE DERIVATIVE

摘要

An industrially advantageous process for the preparation of a pyrazole derivative useful as a herbicide capable of dispensing with isomer separation suffering from low yield and preparation of carboxylic acid necessitating complicated steps, which is represented by reaction formula (IV), (V), (VI), wherein R<1>, R<2> and X<1> are each independently C1-C4 alkyl; R<3> is H or C1-C4 alkyl; X<2> is halogen; X<3> is diazonium salt or halogen; and n is 0, 1 or 2.