Comparative analysis of physicochemical properties of dinuclear zinc(II) helicates with 2,2′-, 2,3′-, and 3,3′-bis(dipyrromethenes)

TLDR: The effect of the attachment position of a methylene spacer in 2,2′-, 2,3′-, and 3, 3′-bis(dipyrromethene) N4-ligands (H2L) on physicochemical properties of dinuclear homoleptic helicates has been examined in this paper.

Abstract: The effect of the attachment position of a methylene spacer in 2,2′-, 2,3′-, and 3,3′-bis(dipyrromethene) N4-ligands (H2L) on physicochemical properties of their dinuclear homoleptic helicates [Zn2L2], such as specific features of their molecular structure, luminescence spectral characteristics, lability in acid solutions, and thermal stability in an argon atmosphere, has been examined It has been shown that the substitution of the biladiene-type helicand by its 2,3- and especially 3,3′-analogues leads to a considerable enhancement of the chromophoric properties, an increase (up to 30-fold) of the fluorescence quantum yield, and an increase in the stability of corresponding dinuclear helicates [Zn2L2]