A host polymer with pending P-cyclodextrin side-groups and a guest polymer with pending hydrophobic 4-tert-butylanilide side groups were synthesized by polymeranalogous reactions starting from poly[(maleic anhydride)-alt-(isobutene)] (aw = 60000). The inclusions of both polymers with complementary monomeric guests and hosts are proven by microcalorimetry. The interaction of the host polymer and the guest polymer in aqueous solution is accompanied by a tremendous increase in viscosity. Recently, Sebille et al.l4) reported on the interaction of a branched P-cyclodextrin polymer with a hydrophobically end-capped polyethylene glycol. They observed an 0 1997, H i i t h i g &

Abstract:The self-assembly of three bis [2]catenanes and a bis [2]rotaxane, by two complementary strategies, is reported. A synthetic route to derivatives of bispur~-phenylene[34]crown-10 (BPP34C 10) and 1,5-naphtho-puru-phenylene[36]-crown-I0 (1/5NPP36C10) containing a fused five-membered ring with a secondary amine function is described. These intermediate N-allylimido macrocyclic polyethers undergo template-directed reactions with 1,1'-[1,4-phenylenebis-(methylene)]bi~-4,4'-bipyridinium bis-(hexafluorophosphate) and 1 ,Cbis(bromomethy1)benzene to produce [2]catenanes containing an N-ally1 functionality. The N-allylimido macrocyclic pol yethers have also been reduced and deprotected to afford macrocycles possessing a free NH group, which are then linked through a 4,4'-biphenyldicarbonyl spacer to produce bis(crown ether)s, in which each crown ether moiety has two recognition sites. These ditopic BPP34C10 and 1/5NPP36C10 derivatives are capable of sustaining self-assembly reactions at both recognition sites to yield bis[2]catenanes. The self-assembly of a complementary bis[2]catenane, in which two tetracationic cyclophanes are linked together with a flexible hexyl chain, has also been achieved by treating 1,l'-[1 ,Cphenylenebis(rnethylene)]bi~-4,4'-bipyridinium bis-(hexafluorophosphate) with a compound containing two linked 1 ,Cbis(bromomethy1)benzene units in the presence of BPP34C10. Replacing BPP34C10 with a dumbbell-shaped compound containing a linear polyether unit intercepted by a naphthalene residue and terminated by two bulky adamantoyl groups has led to the self-assembly of a bis[2]rotaxane. The X-ray crystal structures of one of the catenanes and its associated crown ether component are reported, together with solution state dynamic 'H NMR spectroscopic studies, showing that there is substantial degree of order characterizing the molecular structure of the catenanes.

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The natural phenomenon of self‐assembly has been used to make complex unnatural products. These new compounds have taken the form of catenanes and rotaxanes. We have identified several polymeric architectures containing the catenane and rotaxane motifs, and then described how the model structures, which we have identified and actually realized as chemical compounds, can be employed to assess the feasibility of introducing mechanical linkages into novel polymers by means of self‐assembly processes.

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