Macroligands crosslinked

Different routes are defined by the reaction conditions, nature of the functional groups, MX , and the level of macroligand crosslinking. For example, at a low level of crosslinking (ca. 2% of divinylbenzene), the polymer is flexible enough and the dimer structures B and C form or remain unchanged on complex formatiotL Dimer complexes were nearly unobserved for a 20% of divinylbenzene crosslinked polymer, and coordinatively unsatinated structures (A) can possibly form as well. 

If MX reacts with porous polymers, accessible pores are filled first. Such overgrown pores, which are associated with filling and shielding of the crosslinked macromolecule, is evidence for the MX contribution to a supramolecular buildup of macroligands. Thus it is impossible to predict the effect of a macrohgand pore size on complex formation for macroreticular glycidyl methacrylate-ethylene glycol dimethacrylate copolymer (Fig. 2) since the material has a bimodal and even polymodal pore distribution in radius. Nevertheless, it was shown that insertion of [RhCl(CO)2]2 in a polyamide is accompanied by a shift of the pore size to lower values some... 

The nature of the fimctional groups of the macroligands is also of great importance. For instance, monomeric and polymeric amines dissociate the [Rh(CO)2RS]2 dimer complex in contrast to thiols that yield addition products. Similarly, the nature of the solvent affects chain flexibility and long-range action. For example, the Co complex with a crosslinked PS polymer has a Co L composition of 1 1 (L-monomer unit) in weakly swelling n-hexadecane, whereas a thermodynamically stable 1 2 complex forms in xylene. This observation may be a result of the fact that a PS support is glassy at 70°C in n-hexadecane and gum-like in xylene. 

There is still no resolution on the effect of macroligand stereochemistry on complex formation. A particular case is the formation of a complex between P2ViPy and MCI2 (M = Co, Ni, Cu, Zn). In that case, the order of reactivity is as follows atactic > isotactic > crosslinked. However, the rate of complex formation for isotactic poly(acrylic acid) (PAAc) with Cu is 1.5 times greater than for the syndiotactic form, and the E for these reactions is 6.0 and T.Okcal moP, respectively. 

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