Dithia[9]helicenes: Molecular design, surface imaging, and circularly polarized luminescence with enhanced dissymmetry factors. Issue 38 (13th September 2022)

• Record Type: Journal Article
• Authors: Baciu, Bianca C.; Bronk, Pawel J.; de Ara, Tamara; Rodriguez, Rafael; Morgante, Pierpaolo; Vanthuyne, Nicolas; Sabater, Carlos; Untiedt, Carlos; Autschbach, Jochen; Crassous, Jeanne; Guijarro, Albert
• Is Part Of: Journal of materials chemistry. Volume 10:Issue 38(2022)
• Page Start: 14306
• Page End: 14318
• Publication Date: 2022-09-13
• Subjects: Materials -- Periodicals; Chemistry, Analytic -- Periodicals; Optical materials -- Research -- Periodicals; Electronics -- Materials -- Research -- Periodicals; 543.0284
• DOI: 10.1039/d2tc02910c
• Languages: English
• ISSNs: 2050-7526

Abstract

Abstract : Synthesis of two dithia[9]helicenes by means of a LED-based double photocyclization is reported. Abstract : Synthesis of two dithia[9]helicenes by means of a LED-based double photocyclization is reported. The compounds have sulfur atoms placed at the terminal rings of the helicene, and they display two alternative C 2 -symmetrical arrangements named exo (1 ) and endo (2 ). Separation of enantiomers of opposite helicity allowed the complete characterization 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 ( g lum ) in CPL larger than its isomer exo -dithia[9]helicene (–0.0125 vs. −0.0042). This enhanced g lum 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.