Novel chiral ABBB-type unsymmetrical phthalocyanine. Ring-expansion synthesis, spectroscopic, and electrochemical properties

•Novel chiral ABBB-type unsymmetrical phthalocyanine Zn[Pc(AB3)] was synthesized.•The synthesis employed subphthalocyanine ring-expansion reaction.•CD spectra show the binaphthyl-induced signal in the phthalocyanine absorption range.

A novel chiral ABBB-type unsymmetrical mono(dinaphtho[1,2-e:1′,2′-g]-1,4-dioxocine)-[2,3-b]phthalocyaninato zinc complex Zn[Pc(AB3)] was synthesized via a subphthalocyanine ring-expansion reaction with the addition of an activated chiral binaphthyl-linked phthalonitrile. The resulting pair of phthalocyanine enantiomers has been fully characterized by a series of spectroscopic methods including electronic absorption, CD, MCD, fluorescence, and IR spectroscopy in addition to electrochemistry. The CD measurement with explicit signals over the entire region provides a direct image to the chirality induction from the optically active binaphthyl group to the phthalocyanine chromophore.

Graphical abstractNovel chiral ABBB-type unsymmetrical phthalocyanine was synthesized via achiral subphthalocyanine ring-expansion and characterized by a series of spectroscopic methods as well as electrochemistry.Figure optionsDownload full-size imageDownload as PowerPoint slide