The chameleon-like coordinating ability of 2,3-di(pyridyl)pyrazine-type ligands
This survey is dedicated to the multifaceted modes of binding of metal ions by polyazine N donors like 2,3-di(2-pyridyl)pyrazine (dpp), 5,6-di(2-pyridyl)quinoxaline (dpq) and 9,10-di(2-pyridyl)benzoquinoxaline (dpbq) and related substituted analogs, covered until the end of 2016. These compounds display the potential coordination of the dipyridinopyrazine block consisting of two pyridine and two pyrazine N donor atoms. This report illustrates the structural features of the mono-, di- and multinuclear complexes, whenever crystallographic information was available.