Reversible P-P bond cleavage at an iridium(III) metal centre

Area of Science:

• Organometallic Chemistry
• Coordination Chemistry
• Catalysis

Background:

• Bicyclic diphosphanes are versatile ligands in coordination chemistry.
• Iridium and gold complexes exhibit diverse catalytic activities.
• Understanding ligand reactivity is crucial for designing new catalysts.

Purpose of the Study:

• To synthesize and characterize a novel iridium(III)/gold(I) complex.
• To investigate the reactivity of a bicyclic diphosphane ligand upon coordination.
• To explore carbon-carbon bond activation in a metal complex.

Main Methods:

• Treatment of an iridium(III) complex with a gold(I) precursor.
• Characterization of the resulting heterobimetallic complex.
• Thermolysis studies to induce bond activation.
• Reversal studies using tertiary phosphines.

Main Results:

• Formation of an unusual Ir^III/Au^I complex with a cleaved P-P bond.
• Clean reversal of P-P bond cleavage upon addition of tertiary phosphine.
• Carbon-carbon bond activation within the diphosphane ligand upon thermolysis of the Ir^III/Au^I complex.

Conclusions:

• The P-P bond in bicyclic diphosphanes can be cleaved and reformed in metal complexes.
• Ir^III/Au^I complexes can facilitate C-C bond activation.
• This study opens avenues for developing new catalytic transformations.