Difluorinative-hydroxylation and C-3 functionalization (halogenation/SCN/NO) of imidazopyridine using Selectfluor as fluorine source or oxidant respectively
作者:Saradhi Kalari、Sridhar Balasubramanian、Haridas B. Rode
DOI:10.1016/j.tetlet.2021.153028
日期:2021.5
3-dihydroimidazo[1,2-a]pyridin-2-ol (3m). The Zolimidine drug successfully underwent difluorinative-hydroxylation in high yield. Interestingly, addition of the tetra-n-butyl ammonium halide or NaI or KSCN or NaNO2 in the reaction provided oxidative functionalization of imidazopyridine wherein Selectfluor acted as an oxidant. The C-3 substituted (Cl, Br, I, SCN and NO) imidazo[1,2-a]pyridines were prepared
在水性介质中,已经开发了一种通过使用Selectfluor作为氟源通过咪唑并吡啶的脱芳香基二官能化来进行二氟羟基化的有效途径。该反应通过离子进行,随后通过自由基途径进行。产物以纯净形式获得,无需柱纯化。该方法已成功用于3,3-二氟-2-(4-氟苯基)-2,3-二氢咪唑并[1,2 - a ]吡啶-2-醇(3m)的克级生产。唑来idine啶药物成功地以高收率进行了二氟羟基化反应。有趣的是,加入四正丁基卤化铵或NaI或KSCN或NaNO 2在该反应中,咪唑并吡啶具有氧化功能,其中Selectfluor起氧化剂的作用。以良好的产率制备了C-3取代的(Cl,Br,I,SCN和NO)咪唑并[1,2- a ]吡啶。这两个重要的反应提供了宽泛的官能团耐受性,无金属/无碱和绿色方法。