Syntheses and structures of terminal arylalumylene complexes
Koichi Nagata1, Tomohiro Agou, Norihiro Tokitoh
1Institute for Chemical Research, Kyoto University, Gokasho, Uji, Kyoto 611-0011 (Japan).
New platinum-aluminum complexes featuring terminal arylalumylenes were synthesized. These complexes exhibit shorter aluminum-platinum bonds than previously known, with calculations indicating a strong electrostatic interaction.
Area of Science:
- Organometallic Chemistry
- Main Group Chemistry
Background:
- Aluminum-transition metal complexes are of interest due to their unique bonding and reactivity.
- Previous studies have reported Al-Pt bond lengths, but further investigation into shorter distances and bonding character is warranted.
Purpose of the Study:
- To synthesize novel terminal arylalumylene complexes of platinum.
- To characterize the structural and electronic properties of these new complexes, focusing on the Al-Pt bond.
Main Methods:
- Synthesis of arylalumylene complexes via reaction of dialumene-benzene adducts with platinum precursors or reduction of dibromodialumanes.
- X-ray crystallographic analysis to determine precise bond lengths.
- Density Functional Theory (DFT) calculations to probe electronic structure and bonding character.
Main Results:
- Successful synthesis of two new terminal arylalumylene platinum complexes, [Ar-Al-Pt(PCy3 )2 ].
- X-ray crystallography revealed Al-Pt bond lengths shorter than any previously reported.
- DFT calculations indicated a significant electrostatic component to the Al-Pt bond.
Conclusions:
- The study presents novel platinum-arylalumylene complexes with unprecedentedly short Al-Pt bonds.
- The findings highlight the electrostatic nature of the Al-Pt interaction in these systems.
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