15in which the metal-metal separation more closely approaches that of the bis-(dipyrromethene) macrocycles at 5.145 (1) A, the copper(I1) ions are reduced to copper(1) via one dielectronic step.The variability of the nature of the two one-electron reductions of the dicopper(I1) sites suggests the utility of these complexes as catalysts for the activation of small molecules via concurrent two-electron reductions. Of considerable interest, in view of the simultaneous one-electron reduction steps in the CI-, N3-, and NCSsalts, is the potential of these complexes to catalyze the oxidation of organic substrates. Preliminary results in this direction indicate that the azido complex catalyzes the oxidation of 3,5di-tert-butylcatechol in the presence of molecular oxygen. These studies will be reported in detail elsewhere. (28) Agnus, Y . ; Remy, L.; Gisselbrecht, J.-P.; Weiss, R. J. Am. Chem. SOC. 1984, 106, 93-102.Acknowledgment. Support of this research by the University of Kansas Biomedical Sciences Support Grant 4306-071 1-9 is gratefully acknowledged. K.B.M. thanks Prof. Reynold T. Iwamoto for helpful discussions.Registry No. 1 ( n = 3), 98737-20-3; 3,3'-diethyl-5,5'-diformyl-4,4'dimethyldipyrromethane, 967-68-0; 1,3-propanediamine, 109-76-2; Pb2-(bi-dptmd)(SCN),, 98759-99-0; Zn,(bi-dptmd)(CI),, 98760-00-0; Cu2-(bi-dptmd)(CI),, 98760-01-1; Cu2(bi-dptmd)(CIO4),, 98760-02-2; Cu,-(bi-dptmd)(BF,),, 9308 1-48-2; C~2(bi-dptmd)(N~)~.'/~CH,OH, 98760-04-4; Cu2(bi-dptmd)(SCN),, 98760-05-5; Zn2(bi-dpen)(C1),, 98760-06-6; C~~(bi-dpen)(ClO,)~, 98777-04-9; C~~(bi-dptmd)(N,)~, 98760-03-3; ethylenediamine, 107-1 5-3.

W-exchanged H-ZSM5 was prepared by sublimation of WCl 6 at 673 K followed by hydrolysis of exchanged WCl x species at 523 K. D 2 exchange with residual OH groups showed that each W initially replaced about two zeolitic protons for W/Al ratios of 0.29 and 0.44, consistent with the formation of (WO 2 ) 2+ containing W 6+ species bridging two cation exchange sites. As temperatures reached ∼973 K during D 2 -OH exchange, these species reduced to (WO 2 ) + with the concurrent formation of one OD group. CH 4 conversion turnover rates (per W) and C 2 -C 12 selectivities are very similar to those observed on a Mo/H-ZSM5 sample with similar cation exchange level. As in the case of Mo/H-ZSM5, WO x /H-ZSM5 precursors are initially inactive in CH 4 reactions, but they activate during induction with the concurrent evolution of CO, H 2 O, and an excess amount of H 2 . The reduction and carburization processes occurring during CH 4 reactions and the structure of the exchanged WO x precursors was probed using in situ X-ray absorption spectroscopy (XAS). XAS studies confirmed the isolated initial nature of the exchanged WO x precursors after hydrolysis and dehydration and the formation of WC x clusters ∼0.6 nm in diameter during CH 4 reactions at 973 K. The structural and catalytic resemblance between W-and Mo-exchanged H-ZSM5 is not unexpected, in view of chemical similarities between oxides or carbides of Mo and W. The synthesis of exchanged WO x precursors and their subsequent carburization during CH 4 reactions, however, are more difficult than the corresponding processes for the MoO x counterparts. This may account for previous reports of lower CH 4 reaction rates and aromatics selectivities on W/H-ZSM5 compared with those observed on Mo/H-ZSM5 and with those reported here for rigorously exchanged W/H-ZSM5.

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The fluoride also coprecipitates from halogen fluoride solutions with XeF2 and complexes of XeF2 but not with XeF4.7,8 Recently, Avrorin et al.1 23456789 have reported the preparation of a higher fluoride of radon, either RnF4 or RnF6, and a water-soluble oxide, Rn03, in tracer experiments with isotope 222Rn. They hydrolyzed complex mixtures of products that had been obtained by heating radon, xenon, fluorine, bromine pentafluoride, and either sodium fluoride or nickel fluoride. Part of the radon volatilized on hydrolysis and part remained in the aqueous phase, suggesting the formation of Rn03. However, Avrorin et al. failed to closely examine the contents of the aqueous phase. In this note we report the results of experiments that we have carried out, using larger amounts of reagents and similar conditions, in an effort to confirm their findings. Experimental SectionA Monel reactor (9.05-mL volume) attached to a Monel valve was loaded at room temperature with either NiF2 (16.8-27.7 mmol) or NaF (39.3-42.9 mmol), cooled to -195 °C, and charged with BrFs (15.5-46.4 mmol), 222Rn (49-221 µ ), xenon (0.54-0.57 mmol), and fluorine (54.7-57.1 mmol). Each mixture was heated at 250-265 °C for approximately 40 h. The excess fluorine was pumped off at -195 °C, and BrF5 and uncomplexed XeF6 were vacuum distilled from the reactor at 0 °C. (The XeF6 product was complexes by NaF but not by NiF2). Products remaining in the reactor were then hydrolyzed with 8-15 mL of 0.10 M aqueous Xe03 solution at 0 °C. Radon in the hydrolysate was analyzed by measuring the emissions of its daughters, 214Pb and 214Bi, in equilibrium with their parent.4 The hydrolysate was centrifuged and the supemate transferred to a separate container; the radon was then analyzed in each fraction. The supemate was flushed with nitrogen for 5-10 min and the residue stirred with 10 mL of either water, 0.10 M Xe03 solution, or 1 KI solution; after 4 h, the analyses were repeated.To determine the behavior of radon in simpler mixtures, several experiments were carried out with only radon, fluorine, and NiF2 or with only radon, fluorine, and NaF. Each mixture was heated at

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