Water-soluble macrocycles synthesized via the weak-link approach.

We report a general, high-yielding method for the synthesis of water-soluble complexes, which is based upon the weak-link approach to supramolecular coordination chemistry. Specifically, we have utilized oligomeric ethylene glycol functional groups appended to the aryl groups of the diphenylphosphine moieties to achieve solubility. Small molecules or halide ions can be used to expand these complexes into larger, more flexible macrocyclic structures. The realization of this approach should allow for the preparation of allosteric biomimetic structures which can be used in aqueous media.