Author(s)

Tetsuji Moriguchi^*, Keiichi Mitsumoto, Yuki Nishizawa, Daisuke Yakeya, Venkataprasad Jalli, Akihiko Tsuge

Department of Applied Chemistry, Faculty of Engineering, Kyushu Institute of Technology, Kitakyushu, Japan.

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 1H 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.

Crystal Structure, Thiaheterohelicene Derivative, Strained Structure, Single Crystal X-Ray Study

Moriguchi, T. , Mitsumoto, K. , Nishizawa, Y. , Yakeya, D. , Jalli, V. and Tsuge, A. (2016) Syntheses, Characterization and DFT Analysis of Two Novel Thiaheterohelicene Derivatives. Crystal Structure Theory and Applications, 5, 63-73. doi: 10.4236/csta.2016.54006.