Endo -/ exo - And halogen-bonded complexes of conformationally rigid C -ethyl-2-bromoresorcinarene and aromatic N -oxides

Research output: Contribution to journalArticle


  • Rakesh Puttreddy
  • Ngong Kodiah Beyeh
  • Robin Ras

  • John F. Trant
  • Kari Rissanen

Research units

  • University of Jyväskylä
  • University of Windsor


The host-guest complexes of conformationally rigid C-ethyl-2-bromoresorcinarene with aromatic N-oxides were studied using single crystal X-ray crystallography. Unlike that of the conformationally more flexible C-ethyl-2-methylresorcinarene, the C-ethyl-2-bromoresorcinarene cavity forms endo-complexes only with the small pyridine-N-oxides, such as pyridine N-oxide, 2-methyl-, 3-methyl- and 4-methylpyrdine N-oxide, and quinoline N-oxide. The larger 2,4,6-trimethylpyridine, 4-phenylpyridine and isoquinoline N-oxide, and 4,4-bipyridine N,N′-dioxide and 1,3-bis(4-pyridyl)propane N,N′-dioxide do not fit into the host cavity. Instead endo-acetone complexes are formed. Remarkably, differing from the anti-gauche endo-complex with C-ethyl-2-methylresorcinarene, the flexible 1,3-bis(4-pyridyl)propane N,N′-dioxide guest forms an anti-anti exo-complex with C-ethyl-2-bromoresorcinarene. The endo- and exo-complexes of C-ethyl-2-bromoresorcinarene and studied N-oxides manifest C-O⋯Br, C-H⋯π and C-Br⋯π interactions.


Original languageEnglish
Pages (from-to)4312-4320
Number of pages9
Issue number30
Publication statusPublished - 2017
MoE publication typeA1 Journal article-refereed

ID: 14716278