Introducing Pyridone[α]-Fused BOPHYs as Red-Shifted Bright Fluorophore Potentially Useful as Non-fullerene Acceptors in Donor-Acceptor Dyads.

A series of 2-pyridone[α]-fused BOPHYs - were prepared via a two-step procedure involving the preparation of enamine, followed by an intramolecular heterocyclization reaction. In addition to being fully conjugated with the BOPHY core pyridone fragment, BOPHYs and have a pyridine group connected to the BOPHY core via one- or two -CH- groups. New BOPHYs were characterized by spectroscopy as well as X-ray diffraction.

Electronic Structures of an Annulated -Tetraphenylchlorin and a Related Chlorin Analogue Incorporating an 8-Membered Ring through MCD Spectroscopy and DFT Calculations.

Herein, we compare the electronic structures of the metal-free and nickel(II) derivatives of an annulated -tetraphenyldihydroxychlorin with those of the (metallo)chlorin analogues derived by pyrroline β,β'-ring cleavage of the annulated (metallo)chlorins. These (metallo)chlorin analogues incorporate 8-membered heterocycles in place of the pyrroline, carry oxo-functionalities on the former pyrroline β-carbon atoms, and were previously shown to possess drastically ruffled (twisted) nonplanar conformations. The magnetic circular dichroism spectra of all chromophores investigated feature chlorin-like UV-vis spectra and correspondingly reversed (positive-to-negative in ascending energy) sign sequences in the -band region, indicative of ΔHOMO < ΔLUMO relationships.

Use of Unprecedented Intramolecular 1, 3-Dipolar Cycloaddition Reaction in meso-Nitrile Oxide-Containing BODIPYs as a New Pathway for the Preparation of Fused NIR Platforms.

Meso-nitrile oxide group in 1,7-Diphenyl-containing BODIPYs can be involved in highly unusual [3+2] intramolecular cycloaddition reaction with the formation of the dihydrobenzo[d]isoxazole-containing BODIPYs. Oxidation of these compounds results in the formation of unprecedented either benzisoxazole- or benzo[b]azepine-fused fully conjugated NIR absorbing BODIPYs. The photophysical properties and electronic structures of the target compounds were studied by an array of experimental and theoretical methods.

The fascinating story of axial ligand dependent spectroscopy and redox-properties in iron(II) phthalocyanines.

Iron phthalocyanines play crucial fundamental and applied roles ranging from bulk colorants to components of advanced materials. In this Frontier article, we discuss four aspects concerning the influence of the axial ligands on spectroscopic and redox properties of iron(II) phthalocyanines: (i) iron macrocycle oxidation cite as a function of Lever's parameter; (ii) energy of the metal-to-ligand charge-transfer transitions as a function of Lever's parameter; (iii) iron macrocycle reduction in iron(II) phthalocyanines; (iv) Mössbauer quadrupole splitting as a function of axial ligand binding through the prism of d orbital population.