Asymmetrical Platinum and Rhodium Dinuclear Complex Strongly Bound to Filled d _z2 Complexes by Unbridged Pt−Metal Bonds: Toward Heterometallic-Extended Metal Atom Chains

Heterometallic extended metal atom chains (EMACs) aligned with three types of metal were rationally synthesized by forming unbridged metal−metal bonds based on the interactions between highest occupied and lowest unoccupied molecular orbitals at the d (Formula presented.) orbital. These chains form pentanuclear structures aligned as Rh−Pt−M−Pt−Rh with relatively large formation constants of 5.0×10¹³ M⁻² for M=Pt and 6.3×10¹¹ M⁻² for M=Pd, while retaining their backbones in solution. In the case of M=Cu, the original Cu(+2) atoms were reduced to Cu(+1) during the synthetic process. Cu(+1) has an unprecedented trigonal bipyramidal coordination geometry. The reported synthesis based on asymmetrical dinuclear complexes provides a guideline for the synthesis of hetero-EMACs to allow several analogs through judicious combinations realized by tuning the number of metal nuclei and metal species.