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Title: S N Ar Reaction Toward the Synthesis of Fluorinated Quinolino[2,3,4‐at]porphyrins

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.

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Author(s) / Creator(s):
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Publisher / Repository:
Wiley Blackwell (John Wiley & Sons)
Date Published:
Journal Name:
European Journal of Organic Chemistry
Page Range / eLocation ID:
p. 318-323
Medium: X
Sponsoring Org:
National Science Foundation
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