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Iron complexes [Fen(0PPh3)d2+, Fen(bpy)2?+, Fen(OH2)62+, and FeT131 catalytically activate 1 : 1 HOOW HC1 combinations for the efficient chlorohydroxylation of olefins. The reactive intermediate 7 is not HOC1, but appears to be formed via a Fenton process FenLX2+ (B) [LfFenOOH(BH+)] (1) -(HCl) [LXFe"(OH)C1] (7) + H20). Although the major product from the reaction of 7 with olefin substrates (e.g., cyclohexene, c-C&IIO) is the chlorohydroxo derivative [c-C&o + HOOH + HC1-(FenLx) c-C6Hlo(OH)Cl+ H20], significant amounts of the dihydroxo [ c -C~H~~( O H )~]and traces of the dichloro [ C -C~H~O C~~] derivatives are produced. The reaction efficiency with respect to H O O W C l ranges from 51% for norbornene to 31% for cyclohexene to 10% for 1-hexene. The presence of dioxygen ( 0 2 ) with c-C~HIO results in the production of some ketone [c-C&lg(O)] via oxygenated Fenton chemistry, but does not inhibit the chlorohydroxylation process. The catalyzed process is equally efficient and selective in a biphasic HzOhubstrate solution as in acetonitrile. With cis-stilbene (cis-PhCH=CHPh) the major product is the epoxide ('80%); the reaction efficiency is 63% relative to HOOWCl. These systems chlorinate saturated

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An anionic cobalt(I1) cyanide complex which reversibly binds oxygen inside zeolite Y, Na56[(Si02)136(A102)56].250H20, has been prepared by treating COY with CsC1, followed by the addition of a methanolic solution of NaCN. EPR parameters of the complex inside cesium ion treated COY are characteristic of a five-coordinate Co(CN);-compound. Quantitative gas uptake and EPR measurements show that this complex is highly selective for oxygen binding. Our best sample has an equilibrium constant for oxygen binding of 18 f 2 Torr-', with an oxygen binding cobalt species concentration of 43 f 4 rmol g-' material.

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