Beschreibung:
<jats:title>Abstract</jats:title><jats:p>The single‐step multicomponent self‐assembly of molecular squares featuring four bridging benzobiscarbenes and four Pd<jats:sup>II</jats:sup>(allyl) or Ir<jats:sup>I</jats:sup>(COD) vertices is presented. Four equivalents of the linear benzobisimidazolium salt [<jats:bold>1</jats:bold>](PF<jats:sub>6</jats:sub>)<jats:sub>2</jats:sub> react with two equivalents of [Pd(allyl)Cl]<jats:sub>2</jats:sub> or [IrCl(COD)]<jats:sub>2</jats:sub> in the presence of Cs<jats:sub>2</jats:sub>CO<jats:sub>3</jats:sub> to yield the tetranuclear octacarbene molecular squares [<jats:bold>2</jats:bold>](PF<jats:sub>6</jats:sub>)<jats:sub>4</jats:sub> (M=Pd) and [<jats:bold>3</jats:bold>](PF<jats:sub>6</jats:sub>)<jats:sub>4</jats:sub> (M=Ir), respectively. Compounds [<jats:bold>2</jats:bold>](PF<jats:sub>6</jats:sub>)<jats:sub>4</jats:sub> and [<jats:bold>3</jats:bold>](PF<jats:sub>6</jats:sub>)<jats:sub>4</jats:sub> feature exclusively M–carbon bonds making them the first purely organometallic molecular squares.</jats:p>