Copper Clusters Containing Hydrides in Trigonal Pyramidal Geometry.

Area of Science:

• Inorganic Chemistry
• Organometallic Chemistry
• Materials Science

Background:

• Copper hydrides are important in catalysis and synthesis.
• Previous copper hydride clusters lacked precise structural characterization of hydride positions.
• Development of new synthetic routes for well-defined metal hydride complexes is crucial.

Purpose of the Study:

• To synthesize and structurally characterize novel, precise copper hydride clusters.
• To investigate the coordination environment and bonding of hydride ligands in copper clusters.
• To explore improved synthetic methodologies for these complex structures.

Main Methods:

• Synthesis of copper hydride clusters [Cu11H2{S2P(O^iPr)2}6(C≡CR)3] (R = Ph, C6H4F, C6H4OMe).
• Characterization using single-crystal X-ray diffraction, ESI-MS, multinuclear NMR, and single-crystal neutron diffraction.
• Density Functional Theory (DFT) investigations to understand bonding.

Main Results:

• Successful synthesis of three novel copper hydride clusters (1-3) with 11 copper atoms and two hydride ligands.
• Determination of a unique 3,3,4,4,4-pentacapped trigonal prismatic geometry for the Cu11 core.
• Identification of an unprecedented trigonal pyramidal coordination mode for the two hydride ligands, confirmed by neutron diffraction.
• Observation of hydride resonances at 4.8 ppm in 1H NMR, validated by 2H NMR on deuteride derivatives.

Conclusions:

• The study reports the first structurally precise copper hydrides with an unprecedented hydride coordination mode.
• Improved synthetic routes offer better yields for these complex organometallic compounds.
• DFT analysis provides insights into the electronic structure and bonding of these novel copper(I) hydride clusters.