| abstract |
The present invention relates to a process for preparation of 5-pyrazolemercaptan derivatives represented by the following general formula (I), which is useful for synthesis of sulfonylurea-based herbicides, and an intermediate thereof, <IMAGE> (I) wherein R1 represents hydrogen, C1-C4 alkyl, allyl or propargyl, R2 represents hydrogen, C1-C4 alkyl, or a phenyl group which can contain one or more substituent selected from the group consisting of halogen, nitro and methyl at an optional position, and R3 represents hydrogen, methyl, ethyl or phenyl. |