Complex polymerization

Despite numerous efforts, there is no generally accepted theory explaining the causes of stereoregulation in acryflc and methacryflc anionic polymerizations. Complex formation with the cation of the initiator (146) and enoflzation of the active chain end are among the more popular hypotheses (147). Unlike free-radical polymerizations, copolymerizations between acrylates and methacrylates are not observed in anionic polymerizations however, good copolymerizations within each class are reported (148). 

Triazole, 1-phenyl-derivatives, 5, 752 polymeric complexes, 5, 790 pyrolysis, 5, 108... 

Figure 29.3 Some polymeric complexes (a) Interpenetrating adamantine frameworks in M(CN)2, M = Zn, Cd. (Only M shown straight lines are CN forming linear MCNM rods .) (b) [Zn(acac)2]3, (c) [Cd S=C(NHCH2)2 2(SCN)2], and (d) [M(S2CNEt2)2]2, M = Zn, Cd, Hg. (Note that M is 5-coordinate but with one M-S distance appreciably greater than the other four.)...

According to X-ray data, 2,5-diamino-l,3,4-triazole retains its diamino form in the heterovalent cobalt complex 375 (91IC4858) and in the polymeric complex with manganese thiocyanate (93ICA53). 

Triazole (HL) with Me SAuCl, the gold(I) species, in the presence of potassium hydroxide gives the polymeric complexes [AuL] with exobidentate coordination mode of the azolate ligand (79IC658). 

Dithiocarbamate complexes of copper have been sythesized at a high rate. Reports of new complexes include the morpholine-4- (44), thio-morpholine, AT-methylpiperazine-4-, and piperidine- (291) dithiocarba-mates. Novel, polymeric complexes of the type Cu(pipdtc)2 (CuBr) in = 4, or 6) and Cu(pipdtc)2 (CuCl)4 have been prepared by reactions of[Cu(pipdtc)2] with the respective copper halide in CHCla-EtOH (418). The crystal structures of the polymers are known to consist of sheets of individual [Cu(pipdtc)2] molecules linked to polymeric CuBr chains via Cu-S bonds. A series of copper(I) dtc complexes have been the subject of a Cu and Cu NQR-spectral study (440). 

Six-coordinate, polymeric complexes NCCHj- salen NCCHjCo Not givdn Coplanar to with- 1.99 Co—N, 1.89 Not given 2.09 30... 

The polynuclear derivatives [ AuAg(C6F5)2L J [129, 130] were prepared by reacting the gold derivatives NBu4[Au(C6Fs)2] with Ag[C104], the polymeric complex... 

Figure 3.19 Short gold contacts in the polymeric complexes.

A terpolymer from a family of intramolecular polymeric complexes (i.e., polyampholytes), which are terpolymers of acrylamide-methyl styrene sulfonate-methacrylamido propyltrimethylammonium chloride [106,1418], has been reported. 

The mechanism of ion transport in such systems is not fully elucidated, but it is presumably dependent on the degree of crystallinity of the polymeric complex (which further depends on the temperature and the salt type). The ionic conductivity was initially attributed to cation hopping between fixed coordination sites in the depicted helical tunnel, i.e. in the crystalline part of the polymer. 

Halides are ubiquitous co-ligands for cobalt(III), and are met throughout this review. Anation of (solvent)cobalt(III) complexes by halide has been examined from time to time. An example is substitution of coordinated acetonitrile in [Co(L)(MeCN)2]3+ (L = tetraaza-macrocycle) by Cl-and Br-.1096 A mechanism involving interchange from within tight ion pairs was proposed. Halo-bridged polymeric complexes are well known with both classical and organometallic complexes. 

Oligonuclear and polymeric complexes with other bridging ligands 475... 

The choice of tridentate amine has a critical impact on the coordination mode of the ambidentate nitrite ligand, N02.499,500 Complexes with substituted tri- and tetraamines have shown that bulky substituents may prevent the formation of the -N02 bridged polymeric complexes, and the intramolecular hydrogen network may stabilize N coordination of nitrite. 

The reactions of carbon dichalcogenides other than C02 with Ni° have also been studied quite intensively.2460,2461 Inter alia, Ni polymeric complexes with metallic properties have been prepared using CS2 as the starting material.2462 Some further impetus was given by the observation that CS2 can mimic the binding of CO to the CODH enzyme active site, although CS2 itself does not undergo oxidation/reduction and does not appear to bind to center C (the site of CO oxidation and C02 reduction).2463... 

Peiffer, D.G., Lundberg, R.D., and Turner, S.R. "Intramolecular Polymeric Complexes viscosifiers for Acid, Base and Salt (Aqueous) Solutions," US Patent 4,461,884(1984). 

The green polymeric complex isolated directly from the reaction mixture explodes fairly violently at elevated temperatures. The tetrahydrate produced by recrystallisation from aqueous methanol is also moderately explosive when heated rapidly. 

Figure 10 Structure of the polymeric complex [Me2Zn (C5H4N)CH2CH2CH2 (C5H4N) ] .

Figure 1.23 Protein crosslinking reactions done using homobifunctional reagents can result in large polymeric complexes of multiple sizes and indefinite structure.

Figure 19.14 Hapten-carrier immunogen conjugates can be formed using homobifunctional NHS ester crosslinkers. The reaction may create large polymeric complexes, some of which could precipitate.

The magnetic data of the polymeric complex at low temperature (T < 20 K) yield much higher values than those calculated using Eq. 1 and show strong ferromagnetic interactions. The magnetic behavior of the complex is different from those of discrete Cu-Ln complexes, which normally show antiferromagnetic interactions [81-85],... 

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