Novel Furo-pyridine Derivatives via Sonogashira Reactions of Functionalized Pyridines
作者:Tilman Lechel、Jyotirmayee Dash、Irene Brüdgam、Hans-Ulrich Reißig
DOI:10.1002/ejoc.200800398
日期:2008.7
3-alkoxypyridine derivatives. Apt conditions were developed for their conversion into furo[2,3-c]pyridines. Sonogashira reactions of 4-alkoxy-substituted 3-pyridyl nonaflates allowed an access to regioisomeric furo[3,2-c]pyridines. For both types of alkynyl-substituted alkoxypyridinesan alternative method for cyclization employing iodine monochloride furnished iodinated furo[2,3-c]- or furo[3,2-c]pyridines, which
一系列 4-吡啶基壬二酸酯与几个末端炔烃结合以有效地提供新的 4-炔基取代的 3-烷氧基吡啶衍生物。为它们转化为呋喃 [2,3-c] 吡啶开发了合适的条件。4-烷氧基取代的 3-吡啶基壬二酸酯的 Sonogashira 反应允许获得区域异构呋喃 [3,2-c] 吡啶。对于这两种类型的炔基取代的烷氧基吡啶环化的替代方法,使用一氯化碘提供的碘化呋喃[2,3-c]-或呋喃[3,2-c]吡啶,可以进行第二个钯催化步骤。4-羟基吡啶衍生物 24 用碘碘化得到五取代的吡啶,其在 Sonogashira 反应后立即环化为呋喃吡啶 25。因此,可以从一种前体开始制备三种不同类型的呋喃吡啶。制备的几种化合物具有荧光性并显示出强烈的斯托克斯位移。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)