Process for producing 5-hydroxy-4-thiomethylpyrazole compound
A pyrazole compound represented by general formula (1) is reacted with a sulfur compound represented by general formula (2) in the presence of a base and formaldehyde, to thereby produce a 5-hydroxy-4-thiomethylpyrazole compound represented by general formula (3). The 5-hydroxy-4-thiomethylpyrazole compound may easily be produced in a good yield, by using such a process. Further, this process may easily provide the 5-hydroxy-4-thiomethylpyrazole compound under a mild condition in a single step, without using a special apparatus, an expensive catalyst, or a transition metal, etc. In addition, this process may be conducted substantially without producing a harmful waste which can be derived from a catalyst, etc., and therefore this process is friendly to the environment and industrially valuable.
1. A process for producing a 5-hydroxy-4-thiomethylpyrazole compound, comprising: reacting a pyrazole represented by formula (1):
(Chemical Formula 1)
(wherein R 1 represents a hydrogen atom, an alkyl group, an aromatic hydrocarbon group capable of having a substituent, or a heterocyclic group capable of having a substituent, and R 2 represents an electron-withdrawing group), with a sulfur compound represented by the following formula (2):
(Chemical Formula 2)
X—S (O) n —R 3 (2)
(wherein X represents a hydrogen atom or a metal, R 3 represents an alkyl group, an aromatic hydrocarbon group capable of having a substituent, or a heterocyclic group capable of having a substituent, and n represents 0 or 2) in the presence of a base and formaldehyde, to thereby produce a 5-hydroxy-4-thiomethylpyrazole compound represented by the following formula (3):
(wherein R 1 , R 2 , R 3 and n have the same meanings as those described above).
2. The process for producing a 5-hydroxy-4-thiomethylpyrazole compound according to claim 1 , wherein n is 0.
3. The process for producing a 5-hydroxy-4-thiomethylpyrazole compound according to claim 1 , wherein n is 2.
4. The process for producing a 5-hydroxy-4-thiomethylpyrazole compound according to any one of claims 1 to 3 , wherein the electron-withdrawing group represented by R 2 is a trifluoromethyl group.
5. The process for producing a 5-hydroxy-4-thiomethylpyrazole compound according to any one of claims 1 to 3 , wherein the electron-withdrawing group represented by R 2 is a cyano group.
6. The process for producing a 5-hydroxy-4-thiomethylpyrazole compound according to any one of claims 1 to 3 , wherein the electron-withdrawing group represented by R 2 is an alkoxycarboxyl group, a carboxyl group or a metal salt thereof.