Stepwise Preparation of a Molecular Square from NR,NR‐ and NH,O‐Substituted Dicarbene Building Blocks

A molecular rectangle has been obtained from two equivalents of a dicarbene-bridged dinuclear platinum complex and two equivalents of β,β′-bis(triisopropylsiloxy)phenyl-1,4-diisocyanide. Hydrolysis of the OSi(iPr)3 bonds in this complex leads to the formation of two bridging di(NH,O)-NHC ligands and yields the molecular square (see picture) that features two types of bridging rigid ditopic di-NHC ligands.