A water-soluble Pd4 molecular tweezer for selective encapsulation of isomeric quinones and their recyclable extraction

A molecular tweezer (MT) was obtained by reacting a tetraimidazole donor (L) with a Pd( ii ) acceptor (M). MT was used for multicycle aqueous extraction of phenanthrenequinone (PQ) in high purity from an equimolar mixture of isomeric anthraquinone (AQ) and phenanthrenequinone (PQ).