S N Ar Reaction Toward the Synthesis of Fluorinated Quinolino[2,3,4‐at]porphyrins
S N Ar Reaction Toward the Synthesis of Fluorinated Quinolino[2,3,4‐at]porphyrins
复制标题
DOI：
10.1002/ejoc.202001347
复制
发表时间：
2020-11
影响因子：
2.8
通讯作者：
Damaris Thuita;Matthew J. Guberman‐Pfeffer;C. Brueckner
中科院分区：
文献类型：
--
作者：
Damaris Thuita;Matthew J. Guberman‐Pfeffer;C. Brueckner
氨基五氟苯基取代的金属卟啉的一个氟原子被相邻的β-氨基官能团在分子内的SNAR置换，生成了相应的介氟苯基取代的金属喹啉并[2，3，4-at]卟啉，这是现有的喹啉环化方法所不能获得的。从而制备了铜(II)、镍(II)和锌(II)的配合物。母体的游离碱喹啉并[2，3，4-at]卟啉只能通过铜或锌络合物的脱金属才能获得。环化的中位芳基上剩余的O-氟原子与相邻吡咯部分上的β-氢原子之间的强穿透空间核磁共振光谱耦合为环化提供了明显的光谱特征。喹啉环化显著改变了其光学性质。由于β-氨基官能团的存在，所有的喹啉环状卟啉与Brnsted酸和碱都表现出强烈的卤色反应，这是它们在化学传感应用中潜在应用的先决条件。
An intramolecular SNAr displacement of oneo‐fluorine atom of ameso‐pentafluorophenyl‐substituted porphyrin metal complex by a neighboring β‐amino functionality generated the correspondingmeso‐fluorophenyl‐substituted metallo‐quinolino[2,3,4‐at]porphyrins that are not accessible using established quinoline‐annulation methodologies. The Cu(II), Ni(II), and Zn(II) complexes were thus prepared. The parent free base quinolino[2,3,4‐at]porphyrin is accessible only by demetallation of the copper or zinc complexes. A strong through‐space NMR‐spectroscopic coupling between the remainingo‐fluorine atoms on the annulatedmeso‐aryl group and the β‐hydrogen atom on the adjacent pyrrole moiety provide a clear spectroscopic signature for the annulation. Quinoline‐annulation alters the optical properties significantly. On account of the presence of the β‐amino functionality, all quinoline‐annulated porphyrins show strong halochromic responses with Brønsted acids and bases, the prerequisite for their potential use in chemosensing applications.