Porphyrin polymers

Smith (91) reported an X-ray crystal structure of a zinc porphyrin polymer (77, Fig. 32) where, unusually, the coordination bond is between a nitro group and the zinc center. The tetranitroporphyrin is highly substituted, and the resulting steric hindrance causes the macrocycle to be noticeably distorted. Adjacent porphyrin planes in the polymer are almost orthogonal. However, there is no evidence of polymerization in solution, and the nitro-zinc interaction is probably too weak to maintain this structure outside the solid state. 

Hanack has reviewed a number of phthalocyanine and tetrabenzopor-phyrin shish-kebab porphyrin polymers (102). 

LDMS is particularly well suited for the analysis of porphyrins.35-39 The heme molecule—a 22 rc-electron conjugated protoporphyrin system (Figure 8.1)—is an efficient photo-absorber in the visible and near UV (with an absorption maximum—the Soret band—near 400nm). This feature, concurrently with its low ionization potential, warrants that direct LDMS will possess extremely low limits for heme detection. The uses of IR or UV LDMS for structural characterization of natural porphyrins and their metabolites, synthetic monomeric porphyrins (e.g., used in photodynamic therapy), porphyrin polymers, and multimeric arrays, have been well documented.41148 In addition fast atom bombardment MS has been used to characterize purified hemozoin, isolated from the spleens and livers of Plasmodium yoelii infected mice.49... 

B. Jiang, S.-W. Yang, and W.E. Jones, Jr., Conjugated porphyrin polymers control of chromo-phore separation by oligophenylene vinylene bridges, Chem. Mater., 9 2031-2034, 1997. 

Campidelli et al. have synthesized interesting linear and hyperbranched porphyrin polymers from CNTs via copper-catalyzed alkyne-azide cycloaddition (CuAAC) [122], Zinc porphyrin monomers containing an azide group and one or three alkyne groups were synthesized and chemically bound to alkyne functionalized SWCNTs via CuAAC. Depending upon the number of alkyne functionalities either linear (single alkyne) or dendrimer-like (triple alkyne) porphyrin polymers were produced (Fig. 5.9) [122],... 

Hijazi, I., et al., Formation of Linear and Hyperbranched Porphyrin Polymers onto Carbon Nanotubes via CuAAC Grafting from" Approach. Journal of Materials Chemistry, 2012. 22(39) p. 20936. 

Michelsen, U. and Hunter, C.A. (2000) Selfassembled porphyrin polymers. Angew. Chem., 112, 780-783 Self-assembled porphyrin polymers. Angew. Chem., Int. Ed., 39, 764-767 Mackay, L.G.,... 

Figure 5.56 Schematic illustrating the self-assembled multilayers of sodium 3-mercaptoethane-sulfonate (layer 1 ), hexacationic homooxacalix[3]arene-fullerene (2 1) complex (layer 2 ), with either the anionic porphyrin polymer ( 3 ) or its zinc porphyrin analogue ( 4 ) forming the third layer. Reprinted with permission from A. Ikeda, T. Hatano, S. Shinkai, T. Akiyama and S. Yamada, /. Am. Chem. Soc., 123,4855 (2001). Copyright (2001) American Chemical Society...

The polymers were mainly tested as models for enzymes. The relevant activity for the oxidation of L-glutathion (R-SH— R-S-S-R) was determined by measuring the Oa-consumption. As to be seen from Fig. 4 the optical pure polymers 19 with Fe(III) in the porphyrin) show a higher activity than the DL-form. Generally the low molecular porphyrins have less than 50% activity compared with porphyrins polymer. 

With water separation, isolation of metal porphyrin polymers afterwards purification... 

The yield of the metal free porphyrin polymers containing less than 1 mol% porphyrin (Table 4) is 20-40%. With more than one vinyl group containing porphyrins (56)-(59) no network formation was observed. 

As mentioned earlier the reversible oxygen binding is of fundamental interest in order to construct an artificial oxygen carrier (see Chap. 2.1.2). Results on half life time of few covalent and some coordinative porphyrins are summarized in Table 5. Generally, the polymer Fe(II)-porphyrins are more stable against irreversible oxidation than the low molecular porphyrins. The slow oxidation of polymer Fe(II)-porphyrins is partly inhibited by steric hindering groups at the porphyrin (polymer from 36) (Scheme 1 e — f — g). 

Syntheses, properties, and applications of porphyrin polymers 04MI55. 

H. Nishide, H. Kawakami, T. Suzuki, Y. Azechi, E. Tsuchida, Enhanced stabihty and facilitation in oxygen transport through cobalt porphyrin polymer membranes, Macromolecules 23 (15) (1990) 3714-3716. 

Udal tsov, A.V. (1997) Characterisitcs of donor-acceptor complexes formed in porphyrin-polymer systems and their photoactivation in electron transfer photoreaction, J. Photochem. Photobiol. B Biol., 37, 31-39. 

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