Regarding the synthesis of cecloprid intermediate N-(2-chloro-5-methylpyridine)cysteamine

Thread Content

I hope some expert can help me. Our graduation project requires the synthesis of the pesticide thiacloprid. I majored in chemical engineering and have never been exposed to pesticides. And there are very few literatures on thiacloprid. The only two paragraphs we can find so far are these two paragraphs: Dissolve 2-chloro-5-methylpyridine and 2-aminoethanethiol in acetonitrile respectively. At room temperature, the acetonitrile solution of 2-chloro-5-methylpyridine is added dropwise to the acetonitrile solution of 2-aminoethanethiol under stirring. After the dropwise addition is completed, the temperature is raised to 40°C and stirring is continued for a certain period of time to obtain N-(2-chloro-5-methylpyridine) cysteamine. Add 2.0 g of N-(2-chloro-5-methylpyridine) cysteamine and 1.3 g of cyanodithioimide dimethyl carbonate to 50 ml of ethanol. Under nitrogen protection, the mixture was refluxed for 8 hours under stirring. After the reaction is completed, about 2/3 of the ethanol is distilled off under reduced pressure and left to stand at room temperature. The product crystallizes and is filtered, washed with diethyl ether and then dried to obtain 2.4 g of the product. At present, we have only found relevant data on the second intermediate cyanodithioimide dimethyl carbonate. We cannot find any information on "N-(2-chloro-5-methylpyridine)cysteamine". There is no relevant literature in VIP, China National Knowledge Infrastructure and other databases. We even checked the chemical formulas on CA from 1977 to 2005 and found nothing. I hope some expert can help me find it. What we need now is: The specific conditions and parameters in the process of synthesizing "N-(2-chloro-5-methylpyridine)cysteamine", the instruments required, how to judge and analyze whether "N-(2-chloro-5-methylpyridine)cysteamine" is produced and its yield analysis method. The teacher requires that our plan must be clear and concise, so that he can know at a glance what materials, reagents and instruments must be purchased to conduct the experiment. First of all, I would like to thank my friends who are enthusiastic about helping us find information. My email is binghehacker@sina.com