Synthesis and characterization of trans-[Co(III)(bpb)(amine)2]X (X=NCS, ClO4). X-ray crystal structure of trans-[Co(III)(bpb)(pyrrolidine)2]NCS·0.5H2O containing intermolecular NH⋯OC hydrogen-bonding

A series of complexes of the type trans-[Co(III)(bpb)(amine)2]X (X=NCS, amine=pyrrolidine (prldn) (1), benzylamine (bzlan) (2), and X=ClO4, amine=pyrrolidine (prldn) (3), benzylamine (bzlan) (4), piperidine (pprdn) (5), morpholine (mrpln) (6), and bpb=N,N′-bis(2-pyridinecarboxamide)-1,2-benzene dianion) have been synthesized and characterized by elemental analyses, IR, UV–Vis, and 1H NMR spectroscopy. The crystal and molecular structure of 1·0.5H2O was determined by X-ray crystallography. The compound crystallizes in the triclinic space group P, a=9.4059(8) Å, b=11.3047(10) Å, c=12.8451(11) Å, α=81.984(2)°, β=83.761(2)°, γ=85.456(2)°, V=1341.6(2) Å3, Z=2 and final R1=0.039 (wR2=0.0625) for 5723 independent reflections with I>2σ(I) and 368 parameters. The structure consists of chains of complexes linked by moderately strong NH⋯OC hydrogen-bonds zig-zagging along the c lattice translation. The IR, UV–Vis, and 1H NMR spectra of the complexes are also discussed.