Poly-pseudo-rotaxanes

More recently, Harada et al. applied the complexation process to side-chain systems via Method 6 (Figure 10), in which the guest sites were introduced as pendant groups and thereafter the CD was threaded onto them [104, 105]. Different types of hydrocarbon chain as pendant groups were studied for their compatibility with different CDs. As the cyclic was not blocked, the products can be viewed as side-chain poly(pseudo rotaxane)s of Type 9. Probably because of the rapid exchange process between threaded and unthreaded forms, the isolation of the solid-state polyrotaxane was not reported. 

Figure 1.3.18 Examples of polyrotaxanes and poly-pseudo-rotaxanes.

Not only poly-pseudo-rotaxanes but also polyrotaxanes should be considered trivial topological entanglements, extending the concepts developed for the related molecular entities. By means of ideal continuous deformations we could separate the components of any finite portion of a polyrotaxane. How-... 

CD-based hydrogels can be divided into several classes, as shown in Fig. 11 (a) poly(pseudo)rotaxane hydrogels that contain CDs threaded to precursor-polymer chain ends or (b) to precursor-polymer chain branches (c) hydrogels... 

Fig. 8.3 Schematic illustration for the alignment of the conjugated polymer CP mediated by 3 and the conversion to the poly-pseudo-rotaxane structures 3c...

Poly(pseudo)rotaxanes are special categories of supramolecular pol3miers, which actually are a string of (pseudo)rotaxanes linked by noncovalent bonds. Wang and co-workers creatively introduced ureidopyrimidinone... 

A rotaxane composed of many ring parts is referred to as a poly[ ]rotaxane [6] these, in turn, include mostly main-chain and side-chain polyrotaxanes (Figure 36.1). In main-chain polyrotaxanes, the ring components are threaded along a polymeric axle, to form a polymer of [2]rotaxanes. A variety of polymers can be used as the long axle molecules, ranging from polymethylene chains to aromatic polymers. Among the different types of side-chain polyrotaxane can be included pseudo-polyrotaxanes and poly(2]rotaxanes. 

Topologically linked poly[2]rotaxane is called daisy-chain-type polyrotaxane. Since Stoddart and coworkers attempted to construct a supramolecular poly[2]rotaxane (poly-pseudo[2]rotaxane) in 1998, many researchers have tried to prepare the daisy-chain-type polyrotaxane. However,... 

An alternative approach for the preparation of CD-based polyrotaxane using photoreactions is described (Scheme 9). The authors prepared a-CD-based polyrotaxanes by capping ends of a-CD-PPG complexes, in a pseudo-poly-rotaxane structure, with covalently bound stoppers. A polyrotaxane containing a number of /3-CD molecules was prepared by photoreactions of a precursor complex between /3-CD with PPG having a triphenyhnethyl group at... 

Pseudo)polyrotaxanes containing CB[6J threaded on organic polymers were also reported. Such (pseudo)poly-rotaxanes were synthesized by interfacial polymerization of CB[6]/polyamine pseudorotaxane with diacid chlorides such as 1,6-hexanedioyl chloride (adipoyl chloride). "" Steinke and coworkers recently reported a novel way to produce polyrotaxanes utilizing 1,3-dipolar cycloaddition between azide and alkyne inside the cavity of They also synthesized pseudopolyrotaxanes... 

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