Nonmonotonic assembly of a deep-cavity cavitand.

The synthesis and assembly properties of a new water-soluble deep-cavity cavitand are discussed. For a homologous series of alkanes, the host can form a range of approximately isoenergetic 1:1, 2:1, and 2:2 complexes. As a result of this 'confluence' of binding and assembly the host displays an unusual, nonmonotonic, assembly profile. Thus, no or limited assembly is observed with methane through butane, pentane triggers assembly, and hexane through octane again does not promote assembly, whereas nonane and a larger guest again induce assembly. This unusual behavior is discussed in the context of the diversity of nodes of chemical systems (networks).