Dimerization and polymeric self-arrangement of [HgII(Py)2(PhN2C6H4NNNC6H4R)2] (Py = pyridine; R = NO2) through reciprocal metal-η2-arene π-interactions and non-classical C–H⋯O bonding: Synthesis and X-ray characterization of a polyaryl asymmetric-substitu

Deprotonated 3-(4-phenyldiazophenyl)-1-(4-nitrophenyl)triazene reacts with Hg(CH3COO)2 and pyridine to give red crystals of {[HgII(Py)2(PhN2C6H4NNNC6H4R)2]2}n (Py = pyridine; R = NO2). In the bis-diazo-triazenide complex the tectons [HgII(Py)2(PhN2C6H4NNNC6H4R)2] are linked to pairs as centrosymmetric dimers through reciprocal metal-η2-arene π-interactions. The dimeric units are assembled by translation in the plane ac to unidimensional chains linked through non classical C–H⋯O hydrogen bonds. In the unit cell these 1D chains are related in pairs through an inversion centre. Thus far also no other HgII-Py complexes with two coordinating pyridine molecules were reported.