کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
1315508 | 976036 | 2009 | 5 صفحه PDF | دانلود رایگان |
The synthesis of 3-cyano-2-fluoropyridines from readily available precursors was achieved via nucleophilic substitution of a leaving group in the 2-postion with KF or Bu4NF in polar aprotic solvents such as DMF and DMSO. Ionic tetrahydrothiophenium fragment is the most effective leaving group, the methanesulfonyl moiety is a somewhat less effective, and Br- and Cl- are the least effective. Relatively mild conditions of the reaction between (2-pyridyl)-tetrahydrothiophenium salts and KF, as well as the convenience of one-step synthesis of these salts from 2(1H)-pyridinethiones, make these salts the compounds of choice for the preparation of ring-fluorinated pyridines.
The paper presents the synthesis of 3-cyano-2-fluoropyridines from readily available precursors via nucleophilic substitution of a leaving group in the 2-postion with KF or Bu4NF in polar aprotic solvents such as DMF and DMSO.Figure optionsDownload as PowerPoint slide
Journal: Journal of Fluorine Chemistry - Volume 130, Issue 2, February 2009, Pages 236–240