1. Dithia[9]helicenes: Molecular design, surface imaging, and circularly polarized luminescence with enhanced dissymmetry factors
- Author
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Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Departamento de Física Aplicada, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Baciu, Bianca C., Bronk, Pawel Jaroslaw, Ara, Tamara de, Rodríguez, Rafael, Morgante, Pierpaolo, Vanthuyne, Nicolas, Sabater, Carlos, Untiedt, Carlos, Autschbach, Jochen, Crassous, Jeanne, Guijarro, Albert, Universidad de Alicante. Departamento de Química Orgánica, Universidad de Alicante. Departamento de Física Aplicada, Universidad de Alicante. Instituto Universitario de Síntesis Orgánica, Baciu, Bianca C., Bronk, Pawel Jaroslaw, Ara, Tamara de, Rodríguez, Rafael, Morgante, Pierpaolo, Vanthuyne, Nicolas, Sabater, Carlos, Untiedt, Carlos, Autschbach, Jochen, Crassous, Jeanne, and Guijarro, Albert
- Abstract
We have carried out the synthesis of two dithia[9]helicenes by means of a LED-based double photocyclization. The compounds have sulfur atoms placed at the terminal rings of the helicene, and they display two alternative C2-symmetrical arrangements named exo (1) and endo (2). Separation of enantiomers of opposite helicity allowed the complete characterization of their chiroptical properties in solution, in silico, by X-ray crystallography, and adsorbed on gold. The theoretical analysis confirms the unexpected finding that endo-dithia[9]helicene displays an experimental dissymmetry factor in CPL (glum) larger than its isomer, exo-dithia[9]helicene. This enhanced glum factor ranks among the largest for a helicene-type molecule. Comparison with smaller analogues, namely exo and endo-dithia[7]helicenes (10 and 11, respectively), is also presented.
- Published
- 2022