Rotaxane hybrid

Fig. 23 Solid-state structures of some beautifully novel MIM architectures (a) suit[2]ane [33], (b) eightfold interlocked multicatenane [154], (c) hybrid organic-inorganic [4]rotaxane [88],...

The self-assembly of a hybrid rotaxane (and related pseudocatenanes) incorporating both ammonium and bipyridinium cationic units in the linear components is known. The switchable [2]-rotaxane 46 incorporates one of each of these... 

Further examples of hybrid pseudorotaxanes containing a linear component incorporating two dialkylammonium centres and a 4,4 -bipyridinium unit associated with an assortment of macrocyclic polyethers have been reported. Both multi-component rotaxanes and polyrotaxanes based on the above tetracationic thread were observed to form. The reversible acid-base-controlled dethreading/rethread-ing of such [n]-rotaxanes has been demonstrated using a combination of NMR, absorption and fluorescence spectroscopies. ... 

Fig. 6 Class C SPs. 14 Polyrotaxane " " 15 poly[2]catenane 18 linear dendritic hybrid chain from 7-oxanorbornene monomers substituted with two tapered monodentrons " and 20 SAMs of n-alkanethiolates on gold. Structures 16 [3]catenane and [3] rotaxane with two dibenzol[24]crown-8 rings 17 a-cyclodextrin 4-poly (ethylene oxide) and 19 tobacco mosaic virus are included for comparison.

While the above example unavoidably contains a significant hydrogen bonding contribution to the templation reaction, other systems rely on purely non-directional electrostatic ion pair interactions. A rather impressive demonstration is Leigh and Winpenny s hybrid organic-inorganic rotaxane 7 also from 2010 (Figure 10.5). ... 

FIGURE 10.5 Hybrid organic-inorganic rotaxane 7 containing a cationic ammonium axle and an anionic heterometallic marcocycle. 

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