Magnesium and potassium scorpionate complexes based on dihydrobis(pyrazolyl)borate

Area of Science:

• Organometallic Chemistry
• Crystal Engineering
• Computational Chemistry

Background:

• Magnesium complexes are crucial in catalysis and synthesis.
• Borate anions play significant roles in stabilizing reactive species.
• Understanding novel coordination environments is key to advancing inorganic chemistry.

Purpose of the Study:

• To report the first X-ray crystal structure of a specific magnesium(II) complex.
• To characterize a novel tetrabenzylborate counter-ion and its formation.
• To investigate the structural stability of the synthesized complexes using computational methods.

Main Methods:

• X-ray crystallography was employed to determine the precise structures of the magnesium and potassium complexes.
• Chemical synthesis involving Grignard reagents and potassium borohydride derivatives was utilized.
• Density Functional Theory (DFT) calculations were performed to analyze electronic properties and stability.

Main Results:

• The crystal structure of [dihydrobis(pyrazol-1-yl)borato-κ2N,N']tris(tetrahydrofuran-κO)magnesium(II) tetrabenzylborate revealed a boat-shaped Mg(N-N)2B core with a B-H...Mg interaction.
• A novel tetrabenzylborate counter-ion, [B(C7H7)4]-, was identified, formed from the reaction of KBH4 and benzylmagnesium chloride.
• A polymeric potassium tetrabenzylborate, [K{B(C7H7)4}]n, exhibiting significant aromatic-potassium interactions, was also structurally characterized.

Conclusions:

• The study successfully elucidated the crystal structures of two novel boron-containing magnesium and potassium complexes.
• The findings demonstrate the formation and structural significance of the tetrabenzylborate anion in organometallic chemistry.
• DFT calculations provided insights into the stability and electronic characteristics of the determined molecular structures.