Pyrazolate

Pyrazolynate is a member of the class of pyrazoles that is 1,3-dimethylpyrazole which is substituted at positions 4 and 5 by 2,4-dichlorobenzoyl and p-tosyloxy groups, respectively. It is an obsolete proherbicide (via hydrolysis of the tosylate group to afford the corresponding 5-hydroxypyrazole), that was used to control weeds in rice paddy fields. It has a role as a proherbicide, an EC 1.13.11.27 (4-hydroxyphenylpyruvate dioxygenase) inhibitor, an agrochemical and a carotenoid biosynthesis inhibitor. It is a member of pyrazoles, a tosylate ester, an aromatic ketone and a dichlorobenzene.

1, 3-Dimethyl-4-(2, 4-dichlorobenzene) is prepared from 1, 3-dimethylpyrazolone-5 and 2, 4-dichlorobenzoyl chloride in the presence of solvent and alkali Formyl)-5-hydroxypyrazole (hereinafter referred to as intermediate), and then condensed with p-toluenesulfonyl chloride to prepare pyrazot. Operation process: 164mL tert-butanol, 6g intermediate and 10.4g anhydrous potassium carbonate were refluxed for 1h, and then under the reflux state, the added tert-butanol and the tert-butanol carried out by water were at the same rate. After 2h, Add 11.5g of p-toluenesulfonyl chloride within 15min, and continue to reflux for 1.5h. Then cool to room temperature, filter with suction, combine the filter cake and the filtrate with the residue after removing the solvent, wash twice with a mixture of 200 mL of benzene and 100 mL of water, separate the benzene layer and wash twice with 150 mL of water, and use anhydrous benzene layer After drying with sodium sulfate and debenzene, a light yellow crude product is obtained, and the pure product is obtained after recrystallization from a benzene-hexane (1:1) solution. It is reported in the literature that 5-pyrazolone reacts almost quantitatively with 2, 4-dichlorobenzoyl chloride, and it can promote the release of HCl in the presence of a base and speed up the reaction. 5-benzoyloxypyrazole reacts with 5-pyridine The anion of the oxazolinone reacts to produce the anion of the target DTP. During the reaction, 5-pyrazolone was continuously freed. The presence of a small amount of 5-pyrazolone anion facilitates the reaction. In fact, heating the benzoyloxypyrazole in the presence of an alkali metal carbonate gives a high-yield DTP salt, and the metal salt can also be obtained by the same reaction with a benzoylated compound. However, the use of alkali metal carbonates does not produce by-product benzoic acid, and the use of equimolar amounts of raw materials can produce target compounds. The generated DTP salt continues to be tosylated to obtain pyrazot.

Pyrazole herbicides kill weeds by inhibiting chlorophyll biosynthesis. Control annual and perennial weeds in rice fields. It is selective for rice and barnyardgrass, and can inhibit their growth through the absorption of its roots at the seedling stage of barnyardgrass, rhododendron, artemisia and cattle felt, fireflies, narrow leaf Alisma, etc., and plays a role in controlling weeds. effect. This product can be mixed with a variety of herbicides, and is willing to enhance the effect, can play the role and effect can not be used alone. For example, it can be mixed with triflumuron, glufosinate and butachlor. Generally used in rice fields before sowing or transplanting, 3kg of active ingredient per hectare, 10% granules should be evenly applied by hand or machine under water-retaining conditions when applying.

Molecular Weight:439.3
XLogP3:3.8
Hydrogen Bond Acceptor Count:5
Rotatable Bond Count:5
Exact Mass:438.0207836
Monoisotopic Mass:438.0207836
Topological Polar Surface Area:86.6
Heavy Atom Count:28
Complexity:663
Covalently-Bonded Unit Count:1
Compound Is Canonicalized:Yes