A strontium alumanyl

Area of Science:

• Organometallic Chemistry
• Main Group Chemistry

Background:

• The synthesis and characterization of early transition metal and lanthanide complexes with bulky ligands are crucial for understanding bonding and reactivity.
• Alumanyl anions are a relatively new class of compounds with potential applications in catalysis and materials science.

Purpose of the Study:

• To synthesize and characterize a novel strontium alumanyl complex, [(BDI)SrAl(SiN^Dipp)].
• To investigate the structural and bonding properties of the strontium-aluminum interaction.
• To compare the reactivity of the strontium complex with its lighter calcium analogue.

Main Methods:

• Synthesis of the strontium alumanyl complex using [(BDI)Sr(BPh₄)] and [(SiN^Dipp)AlK]₂.
• Single-crystal X-ray diffraction for structural determination.
• Density Functional Theory (DFT) calculations to analyze bonding and electronic structure.
• Reactivity studies involving tetrahydrofuran (THF) and toluene at elevated temperatures.

Main Results:

• The strontium alumanyl complex [(BDI)SrAl(SiN^Dipp)] was successfully synthesized.
• Structural and computational analyses indicated a marginal involvement of the Sr-Al interaction in the complex.
• Unlike its calcium analogue, the strontium complex did not react with THF.
• The complex underwent dismutation and reaction with toluene at 100 °C, yielding a strontium bis-hydrido(meta-tolyl)aluminate.

Conclusions:

• The strontium-aluminum bond in [(BDI)SrAl(SiN^Dipp)] is weakly interacting.
• The reactivity of the strontium alumanyl differs significantly from its calcium counterpart, particularly in its inertness towards THF.
• The complex exhibits unique reactivity with toluene at higher temperatures, leading to the formation of a strontium bis-hydrido(meta-tolyl)aluminate.