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The paper reports the reactions of the perfluorinated three‐mercury anticrown (o‐C6F4Hg)3 (1) with monohalogenobenzenes. It has been found that the interaction of 1 with fluorobenzene gives two 1:1 complexes 2 and 3, differing in their structures. Complex 2 forms in the crystal extended binary stacks wherein the molecules of 1 alternate with the halogenobenzene species, while complex 3 consists of the cofacial dimers formed from the corresponding monomeric units {[(o‐C6F4Hg)3](C6H5F)}. Each fluorobenzene molecule in both adducts is bonded to 1 by its phenyl ring through secondary π‐Hg–C interactions, whereas the fluorine atom is coordinated with one of the Hg sites of 1. Analogous types of bonding are realized in the chlorobenzene and bromobenzene complexes, {[(o‐C6F4Hg)3]2(C6H5X)4}, (X = Cl, Br), containing four halogenobenzene molecules per two molecules of 1. The complexes include two monomeric {[(o‐C6F4Hg)3](C6H5X)2} fragments connected with one another by two bridging η1 coordinated halogen atoms of the halogenobenzene ligands. The halogen atoms of two other halogenobenzene species are η3 coordinated each with the Hg centers of the neighboring molecule of 1. The reaction of iodobenzene with 1 affords a 3:1 complex, {[(o‐C6F4Hg)3](C6H5I)3}, which is unstable and readily transformed into the corresponding 1:1 adduct. Both compounds form in the crystal extended stacks wherein each sandwiched iodobenzene molecule is coordinated via the iodine atom with the adjacent molecule(s) of 1. [ABSTRACT FROM AUTHOR]

The interaction of the three-mercury anticrown (o-C6F4Hg)3 (1) with [PPh4][BF4] in methanol at room temperature leads to fluoride anion transfer from BF4- to 1 with the formation of a fluoride complex, [PPh4]{[(o-C6F4Hg)3]2F}, having a double-decker sandwich structure. The fluoride ion in this unique adduct is disposed between the mutually parallel planes of the central nine-membered rings of the anticrown units and cooperatively coordinated by all six Hg sites. The iodide anion also forms a double-decker sandwich in the interaction with 1, but this sandwich, [PPh4]{[(o-C6F4Hg)3]2I}, has a wedge-shaped geometry. The reaction of 1 with [nBu4N]Cl in dibromomethane at -15 °C affords a complex, [nBu4N]{[(o-C6F4Hg)3]2Cl(CH2Br2)2}, containing one chloride anion and two coordinated CH2Br2 species per two molecules of 1. A similar bromide complex of 1, containing two coordinated CH2Br2 moieties, has also been synthesized and structurally characterized. Both compounds represent wedge-shaped double-decker sandwiches wherein the halide anion is simultaneously bonded to all Hg centers of the anticrown molecules. The dibromomethane species in the isolated adducts are also arranged in the space between the mercuramacrocycles. One of these species is coordinated by each of its bromine atoms to a single Hg site of the adjacent macrocycle while the other interacts by only one bromine atom with a Hg center of the neighboring molecule of 1. [ABSTRACT FROM AUTHOR]