Inorganica Chimica Acta, I50 (1988) 177-181 177 Crystal and Molecular Structure of E.c-Oxo-bis((5,10,15,20)tetrakispentafluorophenyl)- porphinatoiron(II1) A. GOLD*, K. JAYARAJ University of North Carolina at Chapel Hill, Chapel Hill, N.C. 27514, U.S.A. P. DOPPELT, J. FISCHER and R. WEISS* Universitk Louis Pasteur, Institut le Bel, Strasbourg Ckdex 6 7070, France (Received December 21, 1987) Abstract In this paper, we report the crystal and molecular structure of p-oxo-bis(5 JO,1 5,20)tetrakispentaflu- orophenyl)porphinatoiron(III) [(TPP(Fs)Fe),O] . The crystals belong to the tetragonal system, space group 14r/a, with u = b = 26.362(7), c = 30.886(8) 8, V= 21465 A3, Z = 8 and Dcalc = 1.496. Discrepancy indices are zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA RI= 0.084 and Rz =0.104 for 3320 reflections having I> 3a(& The Fe-N, average distance, 2.088(11) A, is at the long end of the range of high-spin ferric porphyrin while the Fe-O distances (1.775( 1) A) are similar to those of the non-halogenated analog (TPPFe)*O. The Fe-O-Fe angle of 178.4(S)” shows an essentially linear 0x0 bridge. The 0.673(2) A displacement of the iron atom from the porphyrin mean plane is unusually large. The facing porphyrin rings are twisted 47” with respect of each other giving the molecule nearly exact DQd symmetry. here the crystal and molecular structure of /~-0x0- bis((5,10,15,20)tetrakispentafluorophenyl)porphina- toiron(II1) [(TPP(F,)Fe)20] (Fig. 1). This com- pound is of interest not only as a halogenated por- phyrin, but also because the o-fluorine atoms of the meso-phenyl groups appear to offer only marginal encumberance of the iron, permitting the existence of a hydroxo complex under certain conditions [ll]. In addition, the p-oxo-bridged compound exhibits significantly increased antiferromagnetic coupling between the iron centers in the solid state compared to in solution [ 12 1. Introduction The generation of observable high-valent iron monooxygen species from tetramesitylporphinato- iron complexes has evoked considerable interest in the bifacially hindered complexes as models for biological monooxygen transfer catalysis [l-lo] and a number of such compounds have been syn- thesized for this purpose [l, 5,7, lo]. The highly halogenated complexes, zyxwvutsrqponmlkjihgfedcbaZYXWVUTSRQPONMLKJIHGFEDCBA mew 2,6-dichlorophenyl [5] and meso pentafluorophenylporphinatoiron(II1) [I] have proven to be effective catalysts, highly resistant to oxidative degradation. To date, studies on the mechanisms of monooxygen transfer by these compounds have not been complemented by any molecular structure determinations, leaving a gap in knowledge necessary for complete under- standing of the formation and reactivity of the catalytically competent intermediates. We report Fig. 1. ORTEP plot of (TPP(Fs)Fe)zO. Ellipsoids are scaled to enclose 50% of the electron density. Hydrogen atoms are omitted. Experimental *Authors to whom correspondence should be addressed. The p-ox0 bridged complex was synthesized and purified by published methods [12]. The red crys- tals obtained by evaporation of a heptane solution were only marginally suitable for X-ray diffraction. The crystals degraded rapidly on removal from the mother liquor and all manipulations were performed under cold conditions (-20 “C). 0020-1693/88/$3.50 0 Elsevier Sequoia/Printed in Switzerland