The aromatic halogenation of benzo-and dibenzocrown ethers by N-halogenosuccinimides in solid phase, water or organic medium was researched for the first time. Under mechanochemical activation depending on stoichiometry of the process, benzocrown ethers smoothly and selectively transform into corresponding mono or dihalogeno derivatives. Addition of solid N-halogenosuccinimides to benzocrown ethers' water solutions with high yields leads to mono halogenation products. At that, the process proceeds under the action of hypohalogenous acids, i.e. imide hydrolysis products. However, only 4 I ,5 I -dibromo-or -diiodobenzocrown ethers were selectively obtained in 20% solutions of sulphuric acid. In similar conditions, dibenzocrown ethers in solid phase form mixtures of products and do not react with N-halogenosuccinimides in water solutions. In the boiling chloroform medium, the reactivity of investigated macrocycles is vastly varying. If bromination of benzo-and dibenzocrown ethers proceeds easily and with good yields, then under chlorination similar products form with low yields during significantly longer period of time. Only benzocrown ethers out of researched compounds undergo mono iodination at the influence of N-iodosuccinimide. Reaction of Benzocrown Ethers with N-HalogenosuccinoimidesМакрогетероциклы / Macroheterocycles 2008 1(1) 85-89

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The title compound, (cis‐syn‐cis‐icosa­hydro­dibenzo­[b,k][1,4,7,10,13,16]­hexaoxa­cyclo­octadecin)­potassium chloro­chromate, [K(C20H36O6)][CrClO3], is the complex of a potassium cation with one crown ether mol­ecule and a chloro­chromate anion. The cation is situated in the macrocyclic cavity and bonded to the ether O atoms with K—O distances in the range 2.749 (4)–2.991 (3) Å. It also forms two bonds with O atoms of the anion [2.789 (5) and 3.315 (7) Å].

Key indicatorsSingle-crystal X-ray study T = 164 K Mean (C-C) = 0.008 Å Disorder in solvent or counterion R factor = 0.079 wR factor = 0.213 Data-to-parameter ratio = 14.3For details of how these key indicators were automatically derived from the article, see