The active template approach to interlocked molecules

The active template approach to interlocked molecules takes advantage of the ability of metal ions to both organize precursor fragments for mechanical bond formation and to mediate the final covalent bond-forming reaction that captures the interlocked structure. Since its inception just a decade ago, this new methodology has expanded rapidly from a single reaction for rotaxane synthesis to a range of metal-mediated bond formations for the synthesis of complex interlocked molecules. In this Review, we introduce the active template concept, its key advantages for the synthesis of interlocked molecules and outline recent advances that have been made using this technology. We will conclude with comments about future directions and challenges.