MEHDI, and ALFIO CORSINI. Can. J. Chem. 56, 1084 (1978). Metal complexes of water-soluble and other porphyrins have been prepared by a heterogeneous reaction with the metal reactant present in an insoluble form. The oxidation state of the metal is important in the reactions. Metal reactants in the lower oxidation states (0, I, 11) react with porphyrins but those in the higher oxidation states (111, IV) do not. Metalloporphyrins of high purity may be conveniently prepared by this method.OTTO HERRMANN, S. HUSAIN MEHDI et ALFIO CORSINI. Can. J. Chem. 56, 1084 (1978). On a prtpart, par une rtaction htttrogtne avec le mttal reactif present sous une forrne insoluble, des complexes mttalliques de porphyrines dont quelques uns sont soluble~ dans I'eau. L'ttat d'oxydation du mttal est important dans les reactions. Les mttaux reactifs dans des ttats d'oxydation peu eleves (0, I, 11) reagissent avec les porphyrines alors que ceux qui existent dans des ttats d'excitation plus elevts (111, IV) ne reagissent pas. On peut facilement prtpart des mttalloporphyrines de grande purett par cette mtthode.[Traduit par le journal] Introduction The biological importance of certain metalloporphyrins (1) and the variety of interesting and useful properties that they exhibit (2, 3) make metalloporphyrins a widely studied class of compounds. To date, complexes of porphyrins with over fifty metals and semi-metals have been prepared (3). The methods for preparing metalloporphyrins depend upon the nature of the metal to be inserted and, to a lesser extent, upon the type of porphyrin to be used. In general, however, these preparative procedures involve refluxing the porphyrin with a suitable soluble metal salt or metal complex in an appropriate solvent (4a, b, 5). We wish to report on a novel heterogeneous reaction for the formation of metalloporphyrins in which the metal to be inserted is present in an insoluble form rather than in solution with the porphyrin.The heterogeneous metal insertion reaction can be carried out using metal oxides, free metals, metal sulphides, and other insoluble metal salts (e.g., Cu2C12) in water or in non-aqueous solvents. The method has been used successfully to prepare metal complexes of meso-tetraCp-sulphophenyl) porphine (TPPS,), hematoporphyrin (HP), protoporphyrin IX dimethyl ester (PPDME), octaethylporphine (OEP), and meso-tetraphenylporphine (TPP). This type of metalloporphyrin formation reaction has the immediate advantage over the more conventional methods in that the excess metal reactant can be removed from the product by simple filtration of the solid phase rather than by the tedious methods, often in combination, of extraction, precipitation, dialysis, and chromatography.

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sured; the AES results were supported by LEED measurements on the Cu (110) surface (12). Therefore, the estimated accuracy is about &lo%. In general, the systematic error for quantification of the surface coverage by the decrease in the matrix signal (5) is higher and depends mainly on the knowledge of the mean escape depth of the Auger electrons, which may be wrong by f30% (1 7).With conventional trace analysis techniques, e.g., acid digestion in combination with microtitrimetric or spectrophotometric determination of sulfur in metals, a detection limit of 0.2 ppm, an accuracy of typical *IO% at 2 ppm and I f l o % precision can be achieved with about 0.5 g of a sample consumed (18). As compared to these figures, the segregation/ sputtering and AES method shows comparable accuracy, better precision, lower detection limit, and negligible sample consumption (

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