Discrete Rectangles, Prisms, and Heterometallic Cages from a Conjugated Cp*Rh-Based Building Block

Area of Science:

• Coordination Chemistry
• Supramolecular Chemistry
• Organometallic Chemistry

Background:

• Constructing specific coordination geometries can be challenging.
• Existing synthetic strategies may require optimization for novel structures.

Purpose of the Study:

• To propose a new strategy for synthesizing unprecedented coordination structures.
• To utilize a conjugated Cp*Rh-based complex (BN-OTf) as a versatile building block.

Main Methods:

• Density Functional Theory (DFT) calculations to understand electronic properties.
• Controlled synthesis of macrocycles, heterometallic complexes, and cages.
• Single-crystal X-ray diffraction (XRD) and NMR spectroscopy for structural characterization.

Main Results:

• Controllable synthesis of rectangular macrocycles (TN-bpy, TN-bpe) and 1D stacking channels.
• Formation of [4Rh+1M] heterometallic complexes (HMZ) and [8Rh+2M] heterometallic cages (HMC).
• Discovery of triangular prisms (TP-Linker) with novel isomerization via a different synthetic route.

Conclusions:

• The proposed strategy using BN-OTf is effective for constructing diverse and complex coordination architectures.
• The imidazole-4,5-dicarboxylate ligand exhibits flexible coordination modes.
• The synthesized compounds display high yields, crystallinity, and stability.