Syntheses, Characterization and DFT Analysis of Two Novel Thiaheterohelicene Derivatives

Abstract

Two novel thiaheterohelicene derivatives were synthesized from the corresponding 2,2'-(2,6-naphthalenediyl-di-2,1-ethenediyl) bis-thiophene and its dimethyl substituted analogue 2,2'-(2,6-naphthalenediyldi-2,1-ethenediyl) bis-2''-methylthiophene using oxidative photo cyclization reaction. The compounds were characterized by 1 H NMR, electron impact-mass spectrometry, elemental analyses, and the absolute molecular structures were determined by single crystal X-ray diffraction analysis. They crystallized under monoclinic system with space group P2 1 /n for the unsubstituted compound and P2 1 /c for the methyl substituted compound, respectively. The dihedral angle between the terminal thiophene ring and the molecular center was observed to be 20.82˚ for the unsubstituted compound and 14.27˚ for the methyl substituted compound, respectively. Furthermore, molecules oriented as herringbone structures by intermolecular π-π stacking in the crystals. The relative study of the actual arrangement of these molecules has been carried out using X-ray diffraction analysis. The two molecules have different crystal packing. The molecule 3b has herring bone like arrangement due to the substituent bulkiness and weak CH-π interaction. On the other hand, the molecular packing of molecule 3a is not herringbone probably due to the multiple weak intermolecular CH-S short contacts between columns consisting of stacked molecules.

M(NH2SO3)2·xH2O (M = Ca, Pb, x = 0, 1, 4): Effect of Hydrogen Bonding on Structural Transformations and Second Harmonic Generation of Metal Sulfamates

“…X-ray diffraction data were gathered on a Bruker D8 VENTURE diffractometer equipped with Mo-Kα radiation (λ = 0.71073 Å) at 273 K. All data were integrated with SAINT and a multiscan absorption correction using SADABS was applied. Single crystal data of four compounds were handled through ShelXT and ShelXL of the Olex2 interface.…”

Metal Free Synthesis of Coumarin Containing Hetero[n]helicene like Molecules with TICT and AIE Properties

“…[11][12][13][14][15][16][17] Multifunctional helicenes and their derivatives can play a key role in improving the photophysical and optoelectronic properties of twisted helical units. [18][19][20][21][22][23][24][25][26][27][28][29][30] Design and synthesis of such multifunctional helicene is one of the challenging and interesting areas.…”

“…Various synthetic routes have been developed for the synthesis of simple helicenes, heterohelicenes, functionalized helicenes, and multi‐helicene structures [11–17] . Multifunctional helicenes and their derivatives can play a key role in improving the photophysical and optoelectronic properties of twisted helical units [18–30] . Design and synthesis of such multifunctional helicene is one of the challenging and interesting areas.…”