31 results about "Pyridine carboxylate" patented technology

The present invention is preparation process of nifedipine and relates to the field of organic chemical technology. Under the action of pyridine carboxylate in the catalytic amount, o-nitrobenzaldehyde and methyl acetoacetate are made to react to produce intermediate benzylidene compound, which is reacted with methyl acetoacetate and ammonia directly to produce nifedipine. In o-nitrobenzaldehyde,the total yield of re-crystallized nifedipine may reach 70%.

The present invention is preparation process of nifedipine and relates to the field of organic chemical technology. Under the action of pyridine carboxylate in the catalytic amount, o-nitrobenzaldehyde and methyl acetoacetate are made to react to produce intermediate benzylidene compound, which is reacted with methyl acetoacetate and ammonia directly to produce nifedipine. In o-nitrobenzaldehyde, the total yield of re-crystallized nifedipine may reach 70%.

Herbicidal injury caused by 6-(trisubstituted phenyl)-4-amino-2-pyridinecarboxylates in wheat and barley is reduced with the use of AD67 (MON 4660), benoxacor, 2-CBSU, daimuron, dichlormid, dicyclonon (BAS 145 138H), fenchlorazole-ethyl, fenclorim, fluxofenim, furilazole (MON 13900), glyphosate, isoxadifen-ethyl, mefenpyr-diethyl, naphthalic anhydride, oxabetrinil and mixtures thereof.

Herbicidal injury caused by 6-trisubstituted phenyl)-4-amino-2-pyridinecarboxylates in wheat and barley is reduced with the use of low rates of cloquintocet.

Herbicidal injury caused by 6-(trisubstituted phenyl)-4-amino-2-pyridinecarboxylates in wheat and barley is reduced with the use of low rates of cloquintocet.

The invention relates to 3-fluoro-4-aminopyridine, in particular to a synthesis method of 3-fluoro-4-aminopyridine, which mainly solves technical problems such as low yield, difficult separation and purification, and explosiveness in the existing synthesis method. Technical solution: 1) Use 3-fluoropyridine (1A) as a raw material to deprotonate with a strong base and react with carbon dioxide to obtain 3-fluoro-4-pyridinecarboxylic acid or its metal salt (1B); 2) esterify compound (1B) 3) Ammonolysis reaction of 3-fluoro-4-pyridine carboxylate (1C) to generate 3-fluoro-4-pyridine carboxamide (1D); 4) 3- Fluoro-4-pyridine carboxamide (1D) undergoes Hofmann degradation reaction to generate 3-fluoro-4-aminopyridine (1), which is an important intermediate for the synthesis of various new drugs.

The invention discloses a preparation method of idosaban and an intermediate thereof. The preparation method of the idosenban intermediate 4,5,6,7-tetrahydro-5-methyl-thiazolo[5,4-c]pyridine-2-carboxylic acid hydrochloride comprises the following steps: carrying out condensation reaction on 3-bromo-1-methyl-piperidine-4-ketone and thiooxamide ethyl ester in a solvent at the reaction temperature of 50-85 DEG C in the presence of alkali to generate the 4,5,6,7-tetrahydro-5-methyl-thiazolo[5,4-c]pyridine-2-carboxylic acid hydrochloride, and carrying out hydrolysis and hydrochlorination to obtain the intermediate. The invention also relates to a preparation method of the idosaban, including preparing the 4,5,6,7-tetrahydro-5-methyl-thiazolo[5,4-c]pyridine-2-carboxylic acid hydrochloride. Compared with existing methods in references, the method has the advantages of being short in reaction step, high in yield, simple in aftertreatment and the like, the reaction process is controllable, safety is high, and the method is suitable for large-scale production.

The invention discloses a method for synergistic extraction and separation of manganese, calcium and magnesium, comprising: 1) the saponified organic phase containing a synergistic extractant is contacted with an acidic manganese-containing solution containing calcium and magnesium impurities to carry out single-stage or multi-stage countercurrent Extraction; 2) Washing the loaded organic phase with a detergent and contacting the stripping agent with an aqueous solution of inorganic acid for single-stage or multi-stage countercurrent stripping to obtain the stripped organic phase and a high-purity manganese-containing solution; 3) stripping the stripped The organic phase is contacted with the saponification agent for saponification treatment, and the organic phase containing the co-extractant after saponification is obtained, and returned to step 1) for repeated use. The synergistic extractant compounded by phosphoric acid extractant and pyridine carboxylate is used to selectively extract manganese from acidic manganese-containing solution, so as to realize the effective separation of manganese and magnesium ions, calcium ions and other impurity ions, and the loaded organic phase is washed Finally, a mineral acid is used for back extraction to obtain a high-purity manganese-containing solution; the method has a high manganese recovery rate, a good separation effect of manganese and impurities, and is easy to realize industrialization.

In the field of non-ferrous metal hydrometallurgy, the present invention specifically provides an application method of trialkylnaphthalenesulfonic acid, which is added to dialkylnaphthalenesulfonic acid and pyridine carboxylate to speed up the extraction and phase separation; in addition, the present invention The invention also discloses a synergistic extractant containing the trialkylnaphthalene sulfonic acid, including trialkylnaphthalene sulfonic acid, dialkylnaphthalene sulfonic acid and pyridine carboxylate; this recipe also includes the synergistic extraction The preparation of reagents and the application in simultaneous direct extraction of nickel and cobalt from Ni2+, Co2+, Fe3+, Ca2+, Mg2+ and other multi-metal acidic solutions. In the present invention, adding long carbon chain trialkylnaphthalene sulfonic acid to the synergistic extractant containing dialkylnaphthalene sulfonic acid and pyridine carboxylate can significantly improve the extraction and phase separation speed of the extraction agent, so that the extraction clarification rate meets the mixing The requirements of the industrial design of the clarifier do not affect the extraction rate of nickel and cobalt directly extracted from multi-metal acidic solutions containing Ni2+, Co2+, Fe3+, Ca2+, Mg2+, etc. Remove the effect.

The present invention discloses a method for preparing carboxylate by electrochemical dechlorination of trichloromethylpyridine derivatives, which is characterized in that the method comprises the following steps: (1) dissolving polychlorinated pyridine derivatives in alcohol containing electrolytes or phenol solution to obtain an electrolytic reaction solution; (2) using the electrolytic reaction solution as catholyte, carry out electrolytic reduction dechlorination alcoholysis reaction at the cathode to obtain polychloropyridine carboxylate derivatives, and the polychloromethane The base pyridine derivative is shown in formula (I), and the product polychlorinated pyridine carboxylate derivative is shown in formula (II): in formula (I), m is 0, 1, 2, 3 or 4; formula ( II) m and the same formula (I), R is C 1 —C 8 Alkyl, phenyl or phenyl containing functional groups, the beneficial effects of the present invention are mainly reflected in: the reaction can be completed in the next step at normal temperature and pressure; the reaction process does not use concentrated sulfuric acid, thereby avoiding a large amount of difficult-to-handle high COD acidic waste liquid ; Do not use more toxic thionyl chloride and avoid generating sulfur dioxide gas.

Disclosed herein are safened compositions comprising (a) a pyridine carboxylate herbicide or an agriculturally acceptable N-oxide, salt or ester thereof and (b) a quinolinoxy acetate safener or agriculturally acceptable salt or ester thereof. Also disclosed herein are methods of controlling undesirable vegetation, comprising applying to vegetation or an area adjacent the vegetation or applying in soil or water to control the emergence or growth of vegetation (a) a pyridine carboxylate herbicide or an agriculturally acceptable N-oxide, salt or ester thereof and (b) a quinolinoxy acetate safener or agriculturally acceptable salt or ester thereof.