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The interaction of the macrocycle (o,o′‐C6F4C6F4Hg)3 (1) containing three mercury centres with arylphosphonium salts ([Ph4P]Cl or [Ph4P]Br) yields halide complexes, [Ph4P]{[(o,o′‐C6F4C6F4Hg)3](η1:η1‐X)} (X=Cl, Br) having infinite polymer chain structure in the crystal. In both adducts, the halide anion is situated outside of the cavity of the three‐mercury anticrown 1 and bridged by two mercury centres of neighbouring anticrown moieties. At the same time, when mercuracycle 1 interacts with tetraalkylammonium salts ([nBu4N]Cl or [nBu4N]Br), then the discrete 1 : 1 complexes [nBu4N]{[(o,o′‐C6F4C6F4Hg)3](η3‐X)} (X=Cl, Br) of completely different structure are formed. In these halide complexes the anion is located inside the cavity of macrocycle 1 and coordinates the three mercury atoms symmetrically. The synthesized halide complexes [nBu4N]{[(o,o′‐C6F4C6F4Hg)3](η3‐X)} (X=Cl, Br) are the first example of complexes of the macrocycle 1 where it behaves as anticrown. [ABSTRACT FROM AUTHOR]

The paper reports that the interaction of o,o'-dilithiooctafluorobiphenyl with HgCl2 in ether results in the formation of the lithium chloride complex Li{[(o,o'-C6F4C6F4Hg)4]Cl} (11) of the four-mercury anticrown (o,o'-C6F4C6F4Hg)4 (12) along with the earlier isolated and characterized three-mercury anticrown (o,o'-C6F4C6F4Hg)3 (2). The complex was identified by the reaction with 12-crown-4 and determination of the structure of the [Li(12-crown-4)2]{[(o,o'-C6F4C6F4Hg)4]Cl} (13) formed. According to an X-ray analysis, the chloride anion in 13 is simultaneously coordinated with all four Hg centers of the anticrown, forming with them a pyramidal Hg4Cl fragment. The reaction of 11 (in the form of an acetonitrile solvate, 11·nMeCN) with boiling water leads to removal of LiCl from 11 and to the formation of free anticrown 12, the subsequent recrystallization of which from o-xylene affords the o-xylene complex {[(o,o'-C6F4C6F4Hg)4](o-Me2C6H4)2} (14). The obtained 14 forms in the crystal infinite chains consisting of alternating anticrown units and bridging o-xylene moieties. Another o-xylene molecule in each macrocyclic fragment of the chain plays the role of a terminal ligand. In both cases, the o-xylene ligands in 14 are bonded to only one Hg center of the corresponding mercuramacrocycle. The back-conversion of complex 14 into 12 and o-xylene proceeds in the course of its thermal decomposition under vacuum at 100-120 °C. The reaction of 12 with acetonitrile yields the nitrile complex {[(o,o'-C6F4C6F4Hg)4](MeCN)2} (15), which also forms infinite polymeric chains in the crystal. In each monomeric unit of the chain, the corresponding bridging nitrile is bonded to only one mercury atom of the anticrown moiety, whereas the other nitrile ligand is coordinated with two Hg sites. The synthesis and structure of the complex {[(o,o'-C6F4C6F4Hg)4](Me2CO)2(H2O)} (16), containing two acetone and one water ligand per molecule of 12, are also reported. Each acetone molecule in 16 interacts with only one Hg atom of 12, while the water molecule is coordinated with two mercury centers and, in addition, forms H-bonds with the oxygen atoms of the acetone species. [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]

The interaction of the three-mercury anticrown (ο-C6F4Hg)3 1 with a large excess of aqueous [15]crown-5 results in the formation of a complex, {[(ο-C6F4Hg)3]([15]crown-5)(H2O)2} 3, having a polydecker sandwich structure in the crystal. Every double-decker sandwich fragment of this supramolecular aggregate contains one crown ether and two water molecules in the space between the mutually parallel planes of two anticrown units. The water species in 3 are η³-coordinated via the oxygen atom to the Hg centres of the neighbouring anticrown whereas both water protons are involved in the formation of H-bonds with the [15]crown-5. Each crown ether ligand in 3 forms also a weak Hg-O contact with one of the nearest molecules of 1. The reaction of 1 with aqueous [18]crown-6 in methanol leads to a self-assembly of an unusual supramolecular aggregate {[(οC6F4Hg)3]2([18]crown-6)(H2O)2(MeOH)2} 5, containing one crown ether molecule, two molecules of H2O and two molecules of methanol per two anticrown species. The crown ether and water guests in this adduct are sandwiched by two mutually parallel anticrown moieties while the methanol species are located on the free sides of the planes of the mercuramacrocycles and are coordinated with their Hg centres via the oxygen atom in an η³-type. The bonding of the water species in 5 is analogous to that in 3 but the crown ether oxygen atoms form here four shortened Hg-O contacts with the anticrown units. The complex of similar composition and structure, {[(οC6F4Hg)3]2([18]crown-6)(H2O)2(Me2CO)2} 6, is produced when the interaction of 1 with aqueous [18]crown-6 is carried out in acetone as a solvent. [ABSTRACT FROM AUTHOR]