The Synthesis And Application Study Of Fluridiamide And Its Derivatives

Flonicamid is a mature pesticide product at present.There are many different produ ction processes since the product was developed.In industry,the preparation method of Flonicamid is complex,the resource consumption is large,and the yield of Flonicamid i s only about 50%.Therefore,it is of great practical significance to improve the yield an d develop its derivatives.The main research results are as follows:A new type of multi-metal supported catalyst Pd（X）-M（Y）/Al₂O₃（M is transition metal Fe,Cu,Co）was prepared by using the immersion method with alumina calcined at 500℃as the carrier.Various means of characterization.When the transition metal is Fe,X=0.8%,Y=2.7%,the effect of catalytic dechlorination and hydrogenation is the best.The dechlorination and hydrogenation process of 2,6-dichloro-3-cyano-4-trifluoro methylpyridine to 4-trifluoromethylnicotinic acid has been studied.The optimal reaction conditions are:the solvent is isopropanol,the reaction time is 8h,the temperature is 80℃,the amount of Pd（0.87）Fe（2.7）/Al₂O₃ is 10%of 2,6-dichloro-3-cyano-4-trifluorome thylpyridine,and sodium ethoxide is used as the acid binding agent.The speed is 400r/min,and H₂ is used as the donor.The feed ratio of n（4-trifluoromethyl nicotinic acid）:n（aminoacetonitrile hydrochloride）for the synthesis of flonicamid is 1:2.5,reflux for12h in solvent benzene at 80℃.Finally,based on 2,6-dichloro-3-cyano-4-trifluorometh ylpyridine,the total yield of flonicamid was 66%.A three-step method was used to synthesize Flonicamidamidine.The optimal reacti on condition is determined for the first step that 2,6-dichloro-3-cyano-4-trifluoromethyl pyridine dechlorination and hydrogenation to produce 4-trifluoromethylnicotinonitrile.The optimal reaction conditions are:solvent methanol,reaction Time is 16h,temperatur e is 35℃,the amount of Pd（0.87）Fe（2.7）/Al₂O₃ is 5%of the raw material 2,6-dichloro-3-cyano-4-trifluoromethylpyridine,no acid binding agent,The speed is 300r/min,and H₂ is used as the donor.The second step is to synthesize 4-（trifluoromethyl）pyridine-3-c arboximide methyl ester.The optimal reaction conditions are:n（4-trifluoromethylnicoti nonitrile）:（methanol）=1:7,Sodium methoxide is used as a strong base,the reaction tem perature is 60℃,the reaction is 12h,and the reaction yield is stable at 90%.The third st ep is to synthesize flufloxacin.The optimal reaction conditions are:n（4-（trifluoromethyl）pyridine-3-carboximide methyl ester）:（aminoacetonitrile hydrochloride）=1:1.2,toluene as a solvent,the reaction is conducted at 110°C,and the final stable yield is 89.3%.Ba sed on the 2,6-dichloro-3-cyano-4-trifluoromethylpyridine,the total yield of Flonicamid is 71.5%.The insecticidal and antibacterial activities of flonicamid and flonicamid were inve stigated.The experimental results show that the insecticidal activity of Flonicamid and Flonicamid are equivalent.Both Flonicamid and Flonicamid have antibacterial activity.Among them,the compound Flonicamid has antibacterial activity against wheat at 25 m g/L.The inhibition rate of Gibberella is 62.8%.