Porphyrin- and Bodipy-helicene conjugates: syntheses, separation of enantiomers and chiroptical properties

Org Biomol Chem. 2023 Nov 15;21(44):8924-8935. doi: 10.1039/d3ob01459b.

Abstract

The synthesis of several new compounds containing a chromophore and a helicenic moiety is reported. The preparation, characterisation and some physico-chemical studies are detailed. In particular, the two enantiomers of several chiral molecules of this type were separated by chiral HPLC (both analytically and in a preparative way) and their racemisation rates were determined for short-lived species. Electronic circular dichroism (ECD) and circular polarised luminescence (CPL) measurements were performed for the compounds with a very long racemisation half-life. Chiral porphyrins and Bodipys both gave ECD and CPL responses over a large area of the visible spectrum.