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http://dx.doi.org/10.1021/ja00231a039

has been cited by the following article:

• TITLE: Synthesis and Crystal Structure Determination of 4’,9’,4”,9”-Tetra-t-Butyl- 1’,6’,1”,6”-Tetramethoxy-2,5-Dithia[3.3] Metabiphenylophane

  AUTHORS: Tetsuji Moriguchi, Tatsuya Egami, Daisuke Yakeya, Venkataprasad Jalli, Kenji Yoza, Akihiko Tsuge

  KEYWORDS: Crystal Structure, Metabiphenylcyclophane, 1, 2-Alternate Conformers

  JOURNAL NAME: Crystal Structure Theory and Applications, Vol.5 No.3, August 26, 2016

  ABSTRACT: The title compound 4’,9’,4”,9”-tetra-tert-butyl-1’,6’,1”,6”-tetramethoxy-2,5-dithia[3.3] metabiphenylophane was synthesized as a calixarene like large-sized metacyclophane from the corresponding 3,3’-bis(chloromethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl and 3,3’-bis (mercaptomethyl)-5,5’-bis(1,1-dimethylethyl)-2,2’-dimethoxy-1,1’-biphenyl via an intermolecular condensation reaction. The compound was characterized using 1H NMR spectroscopy and mass spectrometry. Its exact conformational structure was determined via single crystal X-ray diffraction analysis. The compound has quite strained 1,2-alternate like structure because of its two high dihedral angled and rigid biphenyl parts in the crystal. The crystal includes the two isomers as two different 1,2-alternate like conformers, and the ratio of the two isomers is 78:22.