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Pyridine compound has a higher biological activity, or less toxic or higher within the suction and selectivity, is widely used in pesticides, pharmaceuticals, dyes, fragrances, surfactants, rubber chemicals, feed additives , food additives, adhesives, synthetic materials, and household chemicals and other areas. Pyridine compound chloride, fluoride, amination can be made into a variety of intermediates, widely used in the field of fine chemicals, quite broad prospects for deep processing, is our urgent development of fine chemicals. Trifluoromethyl group having a strong suction electronic resistance, high permeability of the lipid-soluble and other special features, the introduction of trifluoromethyl aromatic compounds can greatly improve its polarity, stability and lipophilicity, significantly enhanced biological activity, and has many unique the nature, such as the 2 - mercapto-3 - (trifluoromethyl) pyridine, 3 - (trifluoromethyl) -2 - pyridin-sulfonyl chloride and 3 - (trifluoromethyl)-2-z pyridinesulfonamide synthetic pharmaceuticals, pesticides, etc. Important intermediate synthesis of research and development, has broad prospects. This thesis of 2 - mercapto-3 - (trifluoromethyl) pyridine, 3 - (trifluoromethyl) -2 - pyridine sulfonyl chloride and 3 - (trifluoromethyl) -2 - pyridine sulfonamide, investigated a different process conditions , reasonable technology parameters, product and intermediate structures were determined by HPLC, 1HNMR and IR corroborated, and propose a possible reaction mechanism. 2 - chloro-3 - (trifluoromethyl) pyridine in THF - anhydrous ethanol system by one step mercapto reaction Preparation of 2 - mercapto-3 - (trifluoromethyl) pyridine, discussed thiolated reagent choice of the solvent thiolation reaction yield of selection, the amount of solvent, the feed ratio, solvent water and other factors, to determine the optimum process route, ie anhydrous solvent in the presence of ethanol to over sodium sulfide sulfhydryl reagent, m (ethanol): m (2 - chloro-3 - (trifluoromethyl) pyridine) = 3.5:1, n (Guo THF): n-(2 - chloro-3 - (trifluoromethyl) pyridine) = 2:1 refluxed for 6h, and recovered by distillation of the solvent ethanol in the reaction mixture under stirring to adjust the pH of the reaction solution to a value of 2. This method is mild reaction conditions, low equipment requirements, lower cost, higher yield, a yield of 50.0%, greater than 99% purity of the product. - Mercapto-3 - (trifluoromethyl) pyridine in glacial acetic acid - water system, by chlorine oxidation 3 - (trifluoromethyl) - 2 - pyridyl sulfonyl chloride was prepared to investigate the influence on the reaction results of the oxidation reaction temperature, by controlling the chlorine The flow control of the reaction temperature at -10 ° C, yield 74.1%; 3 - trifluoro-methyl-2 - pyridyl sulfonyl chloride by ammonia amination reaction Preparation of 3 - (trifluoromethyl) -2 - pyridine sulfonamide investigated amination the influence of the reaction temperature on the results of the reaction at 0 ℃ amine, 90.2% yield, greater than 99% purity; with 2 - chloro-3 - (trifluoromethyl) pyridine meter, the total yield of the three-step reaction 33.5 %. 2 - amino-3 - (trifluoromethyl) pyridine by diazotization, sulfochlorination reaction Preparation of 3 - (trifluoromethyl) - 2 - pyridyl sulfonyl chloride, investigated the influence of the amount of hydrochloric acid and sodium bisulfite dosage on the reaction, determine Ingredients ratio n (2 - amino-3 - (trifluoromethyl) pyridine) n (sodium hydrogen sulfite): n (concentrated hydrochloric acid) = 1:2:20, yield 73.6%; 3 - (trifluoromethyl) -2 - pyridyl sulfonyl chloride solution with toluene as the extraction agent, 0 ° C, the amination reaction - Pot Preparation of 3 - (trifluoromethyl) -2 - pyridinesulfonamide, yield of 90.0%; 2 - Amino -3 - trifluoromethylpyridine meter, two-step reaction the total yield of 66.2%. Respectively, with 2 - chloro-3 - (trifluoromethyl) pyridine and 2 - amino-3 - (trifluoromethyl) pyridine as the raw material, the use of two different reaction routes Synthesis of 3 - trifluoromethyl-2 - pyridyl sulfonyl chloride and 3 - trifluoromethyl-2 - pyridinesulfonamide, former waste less, but the long route, high cost, low yield; more which waste emissions, but the route is short, easy to operate, low cost, compared with the yield high, is the ideal preparation of 3 - (trifluoromethyl) -2 - pyridinesulfonamide industrialized new method, one of the routes in a pilot and costing. Synthesis of this study the synthesis of three intermediate of pyridine compounds industrialized development has a certain significance.
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