The organic chemistry of poly(1H-pyrazol-1-yl)methanes
Since their first synthesis by Hückel (1937) and the first systematic exploration by Trofimenko (1970), interest in poly(1H-pyrazol-1-yl)methanes (bis, tris and tetrakis) has increased dramatically. This review focuses on the synthesis and reactivity of these ligands and contains 541 different structures and 269 references. After a brief historical introduction, the synthesis, reactivity, and nature of the coordinated metals are described along with some properties of these compounds, particularly the complete set of X-ray molecular structures. All of the formulae are represented to show the extraordinary richness of poly(1H-pyrazol-1-yl)methanes and to promote the use of the already known poly(1H-pyrazol-1-yl)methanes in coordination chemistry and the design of new ligands with the reported procedures.