Silver ion enhanced C-H activation in Pt(II) hydroxo complexes

Area of Science:

• Organometallic Chemistry
• Catalysis
• Materials Science

Background:

• Platinum(II) hydroxo compounds are key intermediates in various catalytic processes.
• Activation of C-D bonds in aromatic compounds remains a significant challenge in synthetic chemistry.
• The role of silver additives in modulating reactivity of platinum complexes is not fully understood.

Purpose of the Study:

• To synthesize novel silver-bound platinum hydroxo complexes.
• To investigate the impact of silver coordination on the catalytic activity of platinum hydroxo complexes.
• To elucidate the mechanism of enhanced aromatic C-D bond activation.

Main Methods:

• Synthesis of neutral Pt(II) hydroxo compounds (NN)Pt(R)(OH).
• Reaction with silver bis(trifluromethanesulfonyl)imide to form new silver-coordinated complexes.
• Characterization using (195)Pt NMR and X-ray crystallography.
• Kinetic studies to determine reaction orders and thermodynamic parameters for C-D bond activation.

Main Results:

• Novel silver-bound platinum hydroxo complexes were successfully synthesized and characterized.
• The silver moiety binds through the Pt-OH bonds, confirmed by spectroscopic and crystallographic data.
• These silver-containing complexes exhibit significantly enhanced rates of aromatic C-D bond activation compared to silver-free analogues.
• Mechanistic studies indicate a bimolecular, homogeneous pathway first-order in both platinum complex and substrate.

Conclusions:

• Silver coordination to platinum hydroxo complexes enhances their ability to activate aromatic C-D bonds.
• The study provides mechanistic insights into silver-promoted C-H functionalization reactions.
• These findings open new avenues for developing efficient catalytic systems for hydrocarbon transformations.