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Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Systematic structural control of multichromic platinum(II)-diimine complexes ranging from ionic solid to coordination
Atsushi Kobayashi1, Hirofumi Hara, Tsubasa Yonemura
1Division of Chemistry, Faculty of Science, Hokkaido University, North-10 West-8, Kita-ku, Sapporo 060-0810, Japan. akoba@sci.hokudai.ac.jp
Dalton Transactions (Cambridge, England : 2003)
|December 16, 2011
Summary
New luminescent platinum complexes with alkaline-earth metals show tunable properties. The dimensionality of their coordination network influences structural flexibility and luminescence, enabling multichromic behavior in some cases.
Area of Science:
- Coordination Chemistry
- Materials Science
- Luminescence Spectroscopy
Background:
- Platinum(II)-diimine complexes serve as versatile metalloligands.
- Alkaline-earth metal ions can influence the assembly and properties of coordination compounds.
- Understanding structure-property relationships in luminescent materials is crucial for developing new technologies.
Purpose of the Study:
- To synthesize and characterize novel luminescent complexes of a Pt(II)-diimine metalloligand with alkaline-earth metals (Mg, Ca, Sr, Ba).
- To investigate the crystal structures and dimensionality of the resulting coordination networks.
- To explore the luminescence properties and stimuli-responsive behavior (thermochromic, mechanochromic, vapochromic) of these complexes.
Main Methods:
- Synthesis of Pt(II)-diimine metalloligand and its reactions with alkaline-earth metal salts.
- X-ray crystallography for determining the crystal structures of the complexes.
- Luminescence spectroscopy, powder X-ray diffraction, thermogravimetry, and IR spectroscopy for property analysis.
Main Results:
- Formation of luminescent complexes: MgPt-4·9H2O, CaPt-4·6H2O, SrPt-4·3H2O, and BaPt-4·5H2O.
- Crystal structures revealed varying coordination networks: discrete molecules (Mg), 2D (Ca), and 3D (Sr, Ba).
- MgPt-4·9H2O exhibited multichromic luminescence (thermo-, mechano-, vapochromic), while CaPt-4·6H2O showed thermochromism.
Conclusions:
- The dimensionality of the coordination network significantly impacts structural flexibility and luminescence.
- Low-dimensional, flexible networks in complexes with smaller alkaline-earth ions facilitate structural rearrangements.
- This rearrangement leads to stimuli-responsive multichromic luminescence, highlighting potential for sensor applications.
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