Luminescent Tetranuclear Copper(I) and Gold(I) Heterobimetallic Complexes: A Phosphine Acetylide Amidinate Orthogonal...

The synthesis of phosphine acetylide amidinate stabilized copper(I) and gold(I) heterobimetallic complexes was achieved by reacting ligand [{Ph₂PC≡CC(NDipp)₂}Li(thf)₃] (Dipp=2,6-N,N'-diisopropylphenyl) with CuCl and Au(tht))Cl, yielding the eight membered ring [{Ph₂PC≡CC(NDipp)₂}₂Cu₂] and the twelve membered ring [{Ph₂PC≡CC(NDipp)₂}₂Au₂]. {Ph₂PC≡CC(NDipp)₂}₂Cu₂] features a Cu₂ unit, which is bridged by two amidinate ligands, served as a metalloligand to synthesize the heterobimetallic Cu^I/Au^I complexes [{(AuX)Ph₂PC≡CC(NDipp)₂}₂Cu₂] (X=Cl, C₆F₅). In these reactions, the central ring structure is retained. In contrast, when the twelve membered ring [{Ph₂PC≡CC(NDipp)₂}₂Au₂] was reacted with CuX (X=Cl, Br, I and Mes), the reaction led to the rearrangement of the central ring structure to give [{(AuX)Ph₂PC≡CC(NDipp)₂}₂Cu₂] (X=Cl, Br, I and Mes), which feature the same the eight membered Cu₂ ring as above. These compounds were also synthesized by a one-pot reaction. The luminescent heterobimetallic complexes were further investigated for their photophysical properties.