title: Multiple Noncovalent Bonding in Halogen Complexes with Oxygen Organics. I. Tertiary Amides.
abstract: The present work describes the structure and binding of adducts of N,N'-diacetylpiperazine with halogens and interhalogens based on combination of different experimental methods and quantum chemical calculations. On the basis of conductometric and spectro-photometric experimental results, behavior of complexes in the acetonitrile solution was described. The iodine adduct with N,N'-diacetylpiperazine fully degrades into components. Adducts of interhalogens I-X (X = Cl or Br) with N,N'-diacetylpiperazine in acetonitrile partially dissociate to anionic [X-I-X](-) and cationic species. In the solid state, molecules are connected via C═O···I, C-H···I, and Cl···Cl attractive interactions. N,N'-diacetylpiperazine···dihalogen complex is stabilized by simultaneous C═O···I and C-H···I interactions. Such binding mode allows to explain the problems of the direct halogenation of acetyl-containing compounds with molecular halogens as reagents. We believe that the observed binding pattern can be used as prototypical for future design of halogeno complexes.
authors.affiliation: X-ray Structural Centre, A.N. Nesmeyanov Institute of Organoelement Compounds, Russian Academy of Sciences , 28 Vavilov Street, Moscow 119991, Russia.
authors.forename: Kyrill Yu
authors.initials: KY
authors.lastname: Suponitsky
authors.affiliation: L. M. Litvinenko Institute of Physical Organic and Coal Chemistry , R. Luxemburg Street 70, 83114 Donetsk, Ukraine.
authors.forename: N I
authors.initials: NI
authors.lastname: Burakov
authors.affiliation: L. M. Litvinenko Institute of Physical Organic and Coal Chemistry , R. Luxemburg Street 70, 83114 Donetsk, Ukraine.|WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde , 295 Cathedral Street, Glasgow G1 1XL, United Kingdom.
authors.forename: Alexander L
authors.initials: AL
authors.lastname: Kanibolotsky
authors.affiliation: L. M. Litvinenko Institute of Physical Organic and Coal Chemistry , R. Luxemburg Street 70, 83114 Donetsk, Ukraine.
authors.forename: Vasilii A
authors.initials: VA
authors.lastname: Mikhailov