Coordination chemistry of anticrowns. Synthesis and structure of a complex of cyclic trimeric perfluoro-o-phenylenemercury (o-C₆F₄Hg)₃ with tungsten hexacarbonyl

The reaction of the three-mercury anticrown (o-C₆F₄Hg)₃ (1) with tungsten hexacarbonyl in CH₂Cl₂ at 20 °C in the dark affords the complex {[(o-C₆F₄Hg)₃]₂[W(CO)₆]} (2) containing two anticrown molecules per W(CO)₆ molecule. According to the X-ray diffraction data, two carbonyl groups of W(CO)₆ are involved in the formation of 2, each of these carbonyl groups being coordinated via the oxygen atom to a single mercury center of one of the two molecules 1. The formation of the complex is accompanied by a shift of ν(CO) bands in the IR spectrum with respect to the corresponding bands of the starting W(CO)₆.