Halogenated porphyrins

The Negishi coupling of halogenated porphyrins has also been described [54,55]. 

Triplet and Singlet Quantum Yields of Halogenated Porphyrin or Bacteriochlorin Sensitizers... 

LjPt(CF3)X complexes (with L = tetraaryldiphosphines and X = CH CIj, OH, OPh) are hydroxylation catalysts of phenol and phenol ethers, with 70% HjO [46]. In all cases, high ortho-selectivity (up to 95%) is observed. Phenylalanine is hydroxylated by a water-soluble iron porphyrin complex to tyrosine and dihydroxy phenylalanine (DOPA) in good yields [47]. Other hydroxylation catalysts of various aromatic substrates are halogenated porphyrin complexes of Fe and Mn [48-49],... 

The oxidation of cyclohexene with dioxygen in SCCO2 has also been reported. The iron(m)-halogenated-porphyrin-catalyzed reaction produced epoxide and allylic oxidation products (Scheme 14). The turnover number (TON) reached up to 1530 for cyclohexene in 24 h at 80°C. The activity is lower in SCCO2 than in organic solvents, but the selectivity for epoxidation (up to 34%) is higher in SCCO2. 

Labinger, J.A. (1994). A simplified model for catalyzed isobutane autoxidation Implications for the mechanism of catalysis by halogenated porphyrin complexes. Catal. Lett. 26,95-99. 

Takeuchi, T., H.B. Gray, and W.A. Goddard, III (1994). Electronic structures of halogenated porphyrins Spectroscopic properties of ZnTFPPXS (TFPPX8 = Octa-beta-halotetrakis (pentafluorophenyl)porphyrin X = Cl, Br). J. Am. Chem. Soc. 116, 9730-9732. 

Silva M, Azenha ME, Pereira MM et al (2010) Immobilization of halogenated porphyrins and their copper complexes in MCM-41 environmentally friendly photocatalysts for the degradation of pesticides. Appl Catal B Environ 100 1—9... 

Wrobel D, Siejak A, Siejak P (2010) Photovoltaic and spectroscopic studies of selected halogenated porphyrins for their application in organic solar cells. Sol Energy Mater Sol CeUs 94(3) 492-500... 

Nevertheless, there are now some oxidation systems that do show catalytic turnover. For example, Breslow has reported a manganese porphyrin equipped with four hydrophobic binding sites in the form of cyclodextrins this mimic of cytochromep450 selectively oxidises unactivated carbon centres that are placed near the metal centre by virtue of the binding geometry (Fig. 3). Catalytic turnover is observed, but oxidative self-destruction of the catalyst competes with the desired chemistry use of a more robust, halogenated, porphyrin has recently solve this problem. ... 

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