A monoamine derivative L of chromium(III) acetylacetonate has been prepared by reduction of a mononitro derivative I. The chelate amine L was" transformed into a stable chelate diazonium fluoroborate N. The diazonium salt was converted into a monofluoro chelate O. Nitration of mono-and dichloro chromium acetylacetonates afforded a series of chloro-, nitro-substituted chelates. Apparent displacement of chloro by nitro was observed during nitration of the dichloro chelate C.Recent reports from this and other laboratories have described the quasiaromatic properties of metal complexes of acetylacetone.16-13 These chelates undergo a wide variety of electrophilic substitution reactions under relatively mild conditions. Stereochemical studies indicate that these substitutions are not attended by opening of the chelate rings.1416 The proton magnetic resonance spectra of unsymmetrically substituted metal acetylacetonates7 and of certain acetylacetone-ethylene diamine complexes16 suggest the presence of aromatic ring current in these substances. Classically, one of the most significant chemical indications of aromatic character is the stabilization of a diazonium ion. This paper reports a successful preparation of a chelate diazonium salt and its chemical properties.Our first attempts to synthesize amino-substituted metal acetylacetonates A, the logical precursors of chelate diazonium salts, were unsuccessful. Attempts at direct amination of the chelate ring failed. Nitro-substituted chelates B, available from a previous study,6seemed fo offer a route to the desired amino chelates A.However, all attempts to reduce nitro groups on the nitrocobalt(III) or rhodium(III) chelates led to reduction of the metals and subsequent decomposition of the complexes.6 On the other hand, chemical or catalytic reductions of the nitro chromium chelate B either afforded unchanged starting material or resulted in intractable mixtures of unidentified products. We had previously experienced difficulty in carrying out trans-

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