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  • Dithia[9]helicenes: Molecular design, surface imaging, and circularly polarized luminescence with enhanced dissymmetry factors
Title: Dithia[9]helicenes: Molecular design, surface imaging, and circularly polarized luminescence with enhanced dissymmetry factors
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.  more » « less
Award ID(s):
1855470
PAR ID:
10412910
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Journal of Materials Chemistry C
Volume:
10
Issue:
38
ISSN:
2050-7526
Page Range / eLocation ID:
14306 to 14318
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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