N-fluoropyridinium salt and process for preparing same
申请人:SAGAMI CHEMICAL RESEARCH CENTER
公开号:EP0204535A1
公开(公告)日:1986-12-10
A pyridine compound is reacted with fluorine together with a Brønsted acid-compound or a Lewis acid to form a N-fluoropyridinium salt which is very active to other compounds but is very selective for the preparation of a desired product and this product is very useful for a fluorine-introducing agent which makes it useful for the preparation of fluoro-compound such as thyroid inhibitor.
counter anion displacementreactions of unstable pyridine-F2 compounds, fluorination of salts of pyridines with protonic acids or silyl esters with F2, and/ or fluorination of Lewis acid complexes of pyridines. The scope of each method was examined in detail. Each of the N-fluoropyridinium salts was assigned as the first stable 1 : 1 salt structure of the pyridine nucleus and halogenatom on the basis
A novel three-component reaction of N-fluoropyridinium salts: a facile approach to imidazo[1,2-a]pyridines
作者:Alexander S. Kiselyov
DOI:10.1016/j.tetlet.2005.04.124
日期:2005.6
The reaction of N-fluoropyridinium triflate with isonitriles in acetonitrile and propionitrile in the presence of NaBH(OAc)3 led to the formation of the corresponding imidazo[1,2-a]pyridines in 44–73% yields. The proposed reaction mechanism involves the intermediate formation of a highly reactive carbene species and apparent reduction of the pyridinium intermediate with NaBH(OAc)3 to yield the targeted
在NaBH(OAc)3存在下,三氟甲磺酸N-氟代吡啶鎓与乙腈和丙腈中的异腈反应,以44-73%的收率形成相应的咪唑并[1,2- a ]吡啶。拟议的反应机理涉及高反应性卡宾物质的中间形成和吡啶鎓中间体与NaBH(OAc)3的明显还原,从而生成目标杂环。