The unprecedented strong paratropic ring current of a bis-PdII complex of 5,10,23-trimesityl [28]heptaphyrin(1.1.0.0.1.0.0).
Chem Sci
; 15(29): 11402-11407, 2024 Jul 24.
Article
in En
| MEDLINE
| ID: mdl-39055025
ABSTRACT
Acid-catalyzed Friedel-Crafts-type cyclization of tetrapyrrolic BF2 complex 1 and α,α'-dibromotripyrrin 2 gave 5,10,23-trimesityl [28]heptaphyrin(1.1.0.0.1.0.0) BF2 complex 3BF2 as a stable and moderate antiaromatic macrocycle. Demetalation of 3BF2 with methanesulfonic acid followed by treatment with HCl gave free-base salt 3HCl that holds a chloride anion at the core. This salt displays a planar structure with an inverted pyrrole and a stronger paratropic ring current. Metalation of neutral free-base 3 with PdCl2 gave bis-PdII complex 3Pd2 as a stable antiaromatic molecule. The 1H NMR spectrum of 3Pd2 displays signals due to pyrrolic ß-protons in the range of -1.06 â¼ -1.90 ppm, indicating the unprecedented strong paratropic ring current.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Language:
En
Journal:
Chem Sci
Year:
2024
Document type:
Article
Country of publication:
Reino Unido