Supramolecular stabilization of alpha,omega-diphenylpolyynes by complexation to the tridentate Lewis acid [o-C6F4Hg](3) Academic Article uri icon

abstract

  • The interaction of trimeric (perfluoro-o-phenylene)mercury ([o-C 6F 4Hg] 3,1) with ,- diphenylpolyynes containing 4, 6, 8, and 12 sp carbon atoms in CH 2Cl 2 leads to the formation of (1) 2 Ph(C=C)2Ph (2), 1Ph(CC)3Ph (3), (1) 2 Ph(CC) 4Ph (4), and (1) 2Ph(OC) 6PhCH 2Cl 2 (5). Adducts 2-4 have been characterized by elemental analysis, X-ray crystallography, infrared and fluorescence spectroscopy, differential scanning calorimetry, and thermogravimetric analysis. In the solid state, the ,- diphenylpolyynes, which are approximately planar, are associated to molecules of 1 on either side of the molecular plane via secondary Hg- interactions. The acetylenic stretches of 2-5 measured by IR spectroscopy are essentially identical with those of the free polyyne. While adducts 3-5 give rise to only faint emissions upon UV irradiation, the luminescence spectrum of 2 indicates complete quenching of the fluorescence and displays a heavy-atom-induced emission whose energy and vibronic progression are identical with those reported for the phosphorescence of the pure diyne. DSC/TGA studies indicate that adducts 2-4 are more thermally stable than the respective free ,-diphenylpolyynes. For Ph(C C) 4Ph, the stability range is increased by almost 120C under an oxidizing atmosphere. Similar conclusions are derived by monitoring the acetylenic stretches of Ph(CC) 4Ph and 4 as a function of temperature in KBr. 2006 American Chemical Society.

published proceedings

  • ORGANOMETALLICS

altmetric score

  • 3

author list (cited authors)

  • Taylor, T. J., & Gabbai, F. P.

citation count

  • 34

complete list of authors

  • Taylor, TJ||Gabbaii, FP

publication date

  • April 2006