A Synthesis Method of Diethyl 5-Ethylpyridine-2,3-Dicarboxylate

摘要

[Objective]This paper was to synthesize the intermediate diethyl 5-ethylpyridine-2,3-dicarboxylate of imazethapyr using 5-ethyl-2,3-pyridinedicarboxylic acid as the raw material.[Method]Diethyl 5-ethylpyridine-2,3-dicarboxylate was successfully synthesized via direct esterification and indirect esterification.[Result]The structure of intermediate was confirmed by LC and1 H NMR.[Conclusion]The intermediate yield of the two methods was both above 89%.Imazethapyr was prepared from the intermediate and the purity reached 99%.