Exploiting Orthogonal C-C Cross-Coupling Reactions for Chemistry-on-the-Complex: Modular Assembly of...

Area of Science:

• Coordination Chemistry
• Organic Synthesis
• Materials Science

Background:

• Ruthenium(II) complexes are versatile in catalysis and materials science.
• Modular assembly strategies are crucial for constructing complex molecular architectures.
• Traditional synthesis routes for ruthenium(II) complexes can be lengthy and involve tedious purification.

Purpose of the Study:

• To develop a concise modular assembly strategy for ruthenium(II)-based molecular architectures.
• To utilize a chemistry-on-the-complex methodology for late-stage functionalization and assembly.
• To employ Suzuki-Miyaura and Sonogashira cross-coupling reactions for efficient C-C bond formation.

Main Methods:

• A universal heteroleptic 2,6-di(quinolin-8-yl)pyridine-based ruthenium(II) complex was synthesized as a building block.
• Functional group interconversions were performed on the building block complex (e.g., bromine to alkyne, azide, boronic ester).
• Suzuki-Miyaura and Sonogashira cross-couplings were used to assemble dyad and triad architectures.

Main Results:

• High isolated yields (≥95%) were achieved for functional group interconversions.
• Dyad and triad molecular architectures were successfully assembled with up to 86% isolated yield.
• Automated flash chromatography simplified purification compared to traditional methods for ruthenium(II) substrates.

Conclusions:

• The developed modular assembly strategy offers an efficient and simplified route to complex ruthenium(II)-based molecular architectures.
• The chemistry-on-the-complex approach facilitates late-stage diversification and optimization of functional units.
• Preliminary characterization indicates potential for energy and electron transfer studies in the synthesized triads.