Zinc complex, with octaethylporphyrin

Nitration of the zinc complex of octaethylporphyrin with nitronium tetrafluoroborate in pyridine proceeds more rapidly than... 

Triplet exclplexes formed from the triplet excited states of zinc and magnesium etioporphyrin I (ZnEtio I and MgEtlo I) and zinc octaethylporphyrin (ZnOEP) with acceptors such as nitro-aromatics and organochloro compounds were directly observed by conventional flash spectroscopy (250-252). The nature and decay properties of the exclplexes are sensitive to quencher concentration and medium composition. For example, as the concentration of para-nitrotoluene (PNT) was Increased in benzene solutions of ZnEtioI, the lifetime of the transient observed after flash excitation of the metal complex proportionately Increased up to a maximum and then decreased (250). The first effect was attributed to the formation of long-lived exclplexes involving two PNT molecules as shown in the scheme below, where D = metallopor-phyrin and A = PNT ... 

A number of diazo compounds are known to be decomposed by Zn(II), Co(II), Co(ni) and Rh(III) complexes of porphyrins (409) to give 1 1 and 1 2 adducts between the porphyrin and the formal carbene unit. Depending on the metal ion, different products may result (Scheme 42) Zinc octaethylporphyrin or meso-tetraphenylporphyrin yield N-alkylated porphyrins 410 with ethyl diazoacetate and ethyl 2-diazopropionate In the latter case, a homoporphyrin 411 is obtained additionally. Cu(I)-catalyzed decomposition of diazomethane or alkyl diazoacetates in the presence of zinc me.yo-tetraphenylporphyrin leads to cyclopropanation of a pyrrolic pp double bond, besides an N-alkylated product of type 410 The... 

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