Double-Sandwich Pentalene Complexes M₂(pent^†)₂ (M = Rh, Pd; pent^† = 1,4-Bis(triisopropylsilyl)pentalene): Synthesis, Structure, and Bonding

The bis­(pentalene) complexes M₂(pent^†)₂ (M = Rh (<b>1</b>), Pd (<b>2</b>); pent^† = 1,4-bis­(triisopropylsilyl)­pentalene) have been synthesized and structurally characterized. In both <b>1</b> and <b>2</b> the metals have a formal electron count in excess of 18 per metal center, and DFT calculations indicate antibonding metal–metal interactions are present in <b>1</b>, whereas <b>2</b> involves antibonding metal–ligand interactions