Luminescent, Redox-Active Diphenothiazine Dumbbells Expanded by Conjugated Arenes and Heteroarenes
作者:Martina Hauck、Raluca Turdean、Karin Memminger、Jan Schönhaber、Frank Rominger、T. J. J. Müller
DOI:10.1021/jo101997t
日期:2010.12.17
Dumbbell-shaped diphenothiazines bridged by conjugatively linked (hetero)aromatic moieties were synthesized in a modular fashion by Suzuki-Miyaura coupling in good yields. The electronic structure was studied by DFT computations, determining the geometry optimized lowest energy conformers and scrutinizing the Kohn-Sham FMOs. The torsional deviation from coplanarity is predominantly influencing the electronic structure, i.e., by deviation from ideal overlap and maximal electron transmission. The reversible oxidation potentials assigned to the phenothiazinyl electrophores in most cases can thereby be qualitatively rationalized. All dumbbell-shaped diphenothiazines are strongly luminescent, which can be attributed to extended pi-electron conjugation with considerable excited state electronic coupling as a consequence of large structural and electronic distributional changes upon photoexcitation.