Halogen bonds in 2,5-dihalopyridine-copper(II) chloride complexes
Abstract
Ten coordination complexes obtained through a facile reaction between 2,5-dihalopyridines and copperIJII)
chloride (CuCl2) are characterized using single crystal X-ray diffraction. Two series of dihalopyridine complexes
based on 2-chloro-5-X-pyridine and 2-bromo-5-X-pyridine (X = F, Cl, Br and I) were prepared to
analyze the C–X2/X5⋯Cl–Cu halogen bonds (XB). The influence of X2- and X5-substituents on the respective
interactions was examined by comparing them to the X2/X3⋯Cl–Cu XBs found in mono-substituted
halopyridine complexes, (n-X-pyridine)2·CuCl2 (n = 2, 3 and X = Cl, Br and I). Varying the X5-halogens in
(2,5-dihalopyridine)2·CuCl2, the C5–X5⋯Cl–Cu XBs follow the order F5 < Cl5 < Br5 < I5 for X2 = Cl and
Cl5 < Br5 < I5 for X2 = Br. The C2–X2⋯Cl–Cu XB distances did not follow any particular trends, and are
slightly longer compared to corresponding distances in (2-halopyridine)2·CuCl2 complexes due to the
competition of X2 and X5-halogen based halogen bonds. The C3–X3⋯Cl–Cu contacts in (3-halopyridine)2
·CuCl2 have RXB values > 1 and they cannot be considered as halogen bonds. This proves the polarization
effect of X2- to X5- rather than X5- to X2-halogen, and the introduction of second halogen substituent in
para-position to X5- triggers C2–X2⋯Cl–Cu and C5–X5⋯Cl–Cu XB interactions.
Main Authors
Format
Articles
Research article
Published
2018
Series
Subjects
Publication in research information system
Publisher
Royal Society of Chemistry
The permanent address of the publication
https://urn.fi/URN:NBN:fi:jyu-201805222703Use this for linking
Review status
Peer reviewed
ISSN
1466-8033
DOI
https://doi.org/10.1039/C8CE00209F
Language
English
Published in
CrystEngComm
Citation
- Puttreddy, R., von Essen, C., Peuronen, A., Lahtinen, M., & Rissanen, K. (2018). Halogen bonds in 2,5-dihalopyridine-copper(II) chloride complexes. CrystEngComm, 20(14), 1954-1959. https://doi.org/10.1039/C8CE00209F
Funder(s)
Research Council of Finland
Research Council of Finland
Funding program(s)
Akatemiahanke, SA
Tutkijatohtori, SA
Academy Project, AoF
Postdoctoral Researcher, AoF
![Research Council of Finland Research Council of Finland](/jyx/themes/jyx/images/funders/sa_logo.jpg?_=1739278984)
Additional information about funding
The authors gratefully acknowledge financial support from the Academy of Finland (RP: grant no. 298817, ML: grant no. 277250) and the University of Jyväskylä.
Copyright© The Royal Society of Chemistry 2018