Stereoselective Synthesis of a Topologically Chiral Solomon Link

Abstract

With the help of retrosynthetic analysis, we have realized the highly anticipated stereoselective synthesis of a topologically chiral Solomon link, by taking advantage of coordination-driven self-assembly and chiral induction by axially chiral ligands. Combination of the ligands (<i>R</i> or <i>S</i>)-2,2'-diethoxy-1,1'-binaphthyl-6,6'-bis(4-vinylpyridine) (<i>R</i><b>-L</b> or <i>S</i><b>-L</b>) with the binuclear iridium complex [Cp*₂Ir₂(DHBQ)(OTf)₂] (<b>Ir-B</b>(OTf)₂, H₂DHBQ = 2,5-dihydroxy-1,4-benzoquinone) allows diastereoselective synthesis of the topological enantiomers <i>P</i> (<b>Ir-1</b><i>P</i>) or <i>M</i> (<b>Ir-1</b><i>M</i>) of a Solomon link, respectively. The main driving force for the formation of the Solomon link is the π-π interactions between chiral ligands.