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Title: Fluoro-2,6-dimethylphenyl mono-hydroxychlorin and porphyrin congeners
Mono-hydroxychlorins are uncommon macrocycles that have only been synthetically realized by modifying porphyrin rings using the harsh oxidizing agent OsO4. We show here that a more directed delivery of the mono-hydroxychlorin may be concomitantly obtained from the oxidation of porphyrinogen using the mild conditions of the high dilution Lindsey porphyrin forming reaction where water content is minimized by using dry CHCl3within the environment of a glovebox. We now report the direct synthesis of 17,18-dihydro-18-hydroxy-5,10,15,20-tetrakis-(4-fluoro,2,6-dimethylphenyl)-porphyrin (2H-TFChl-[Formula: see text]OH) together with the corresponding freebase porphyrin TFP. The TFP has been metalated with FeBr2and MgBr2•OEt2resulting in metalloporphyrins Fe(III)TFP(Cl) and Mg(II)-TFP which have been structurally characterized by single-crystal X-ray crystallography. We find that the excited state properties of the mono-hydroxychlorin are similar to that of its parent TFP and Mg(II)TFP porphyrin congeners. Excited state deactivation by vibronic coupling to the high energy O-H oscillator is circumvented with the hydroxyl group remote to the 18[Formula: see text]-electron framework of the chlorin ring. These results reveal that strong H-bonding groups may be introduced on the periphery of the chlorin ring while maintaining the light-gathering properties that lie at the heart of photosynthesis of the chlorin ring.  more » « less
Award ID(s):
2216066
PAR ID:
10659087
Author(s) / Creator(s):
 ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  ;  
Publisher / Repository:
World Scientific
Date Published:
Journal Name:
Journal of Porphyrins and Phthalocyanines
Volume:
27
Issue:
12
ISSN:
1088-4246
Page Range / eLocation ID:
1650 to 1658
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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