Pendant group functionalization

The living polymerization process offers enormous flexibiUty in the design of polymers (40). It is possible to control terminal functional groups, pendant groups, monomer sequencing along the main chain (including the order of addition and blockiness), steric stmcture, and spatial shape. 

The synthetic methods of macromolecules having an active pendant group include (1) the transformation reactions of polymer and copolymers, and (2) polymerization and copolymerization of functional monomers having active pendant groups. The macromolecules, either in the shape of film or microbeads, can be used as the substrate. As we have mentioned previously, the rate of polymerization initiated with the Ce(IV) ion redox system is much faster than that initiated by Ce(l V) ion alone, as expressed in / r 1. Therefore, the graft... 

Two compounds of this type, T8[c-C5H9]8 and Tslc-CeHnls (Table 31, entries 1 ) are of particular interest not because of the nature of their pendant groups which are difficult to functionalize (a few examples of the use of such compounds as polymer nanofillers have been reported), but because they are the precursors to compounds with TsRyR structures (R = C-C5H9 or c-CeHu) as described at the end of this section. 

The polyphosphazenes are high molecular weight polymers with a wide range of novel and potentially useful properties. The large number of different pendant groups with widely varied functionality which can be attached to the P-N backbone demonstrate the unusual molecular design potential of this class of polymers. Undoubtedly, some of these will hold promise for future research and development. 

The large number of different pendant groups with widely varied chemical functionality which can be attached to the... 

NHC ligands with a pendant group that enforces chelation have also been coordinated to copper centers. The reaction of Cu20 with pyridine fV-functionalized carbene ligand led to the formation of several compounds.91 In the case of mesityl derivatives, a dinuclear complex with a weak metal-metal interaction was isolated 60,91 whereas for the bulkier 2,6-diisopropylphenyl group, a monomeric complex was formed and characterized 61 (Figure 25).91... 

The sulfimide group R2S = NR is isoelectronic with R2S = O, and recent studies have revealed the first examples of macrocyclic derivatives from reaction of the thia crown with MSFI.155,156 These compounds are of interest as ligands in their own right, and also because they provide a means of functionalizing the thiacrown at the S atom and hence the possibility of introducing pendant groups. 

Hiller and Funke extensively investigated the change of the polymer structure as a function of the monomer and the initiator concentration in various solvents [231]. The content of pendant vinyl groups in the polymer was about 100% for n-BuLi concentrations below 2 mol % and for the whole range of the monomer concentration studied (20-100 g/1). The content of pendant groups decreased when the n-BuLi concentration increased and approached 80% in the transition region of a soluble polymer to a macrogel. As seen in Fig. 45, the decrease of pen-... 

Products of substitution of inosine and guanosine 5 -monophosphate for chloride or for water on ternary aminocarboxylate complexes such as [Pd(mida)(D20)], where mida = IV-methyliminodiacetate, or [Pd2(hdta)Cl2]2-, where hdta = 1,6-hexanediamine-A(7V,./V,./V,-tetraace-tate, is subject to mechanistic controls in terms of number of coordinated donor atoms and pendant groups and of the length of the chain joining the functional groups in the bis-iminodiacetate ligands. These factors determine the nature and stereochemistry of intermediates and the relative amounts of mono- and bi-nuclear products (253). 

Fang and Yamamoto [351] reported on postpolymerization functionalization of triarylamine-fluorene copolymer 253, resulting in copolymers 254a,b with stilbene pendant groups. Whereas in the solid-state absorption and PL maxima of both polymers are essentially the same, PL in solution is strongly influenced by solvent (from 433 nm in toluene to 466 nm in jY-methylpyrrolidone). Copolymer 254a showed d>PL in the solid state of 51%, comparable to that of poly(9,9-dialkylfluorenes) (Chart 2.66). 

Polyacrylates Containing the Hexafluoroisopropylidene Function in the Pendant Groups... 

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