Crystal and molecular structures of {NN′-[2-(2′-pyridyl)ethyl]ethylenebis(salicylideneiminato)}-iron(II) and -cobalt(II)–ethanol (1/1)

Abstract

The crystal and molecular structures of the title complexes, [Fe(salpeen)](1) and [Co(salpeen)]·EtOH (2), have been determined using three-dimensional X-ray diffraction data collected on automatic diffractometers. Complex (1) crystallises in the monoclinic space group P2₁/c with the unit-cell parameters a= 10.572(2), b= 11.465(2), c= 16.640(3)Å, β= 90.52(1)°, and Z= 4, and its structure has been refined by conventional least-squares techniques using 1 118 reflections having I > 3σ_I to give R 0.056 and R′ 0.062. Complex (2) crystallises in the triclinic space group P with the unit-cell parameters a= 15.049(2), b= 15.127(2), c=10.258(1)Å, α= 90.53(l), β= 93.53(1), γ= 109.81 (1)°, and Z= 4, and its structure has been refined using 1 237 reflections having I > 3σ_I to give R 0.064 and R′ 0.069. The cobalt complex thus has two crystallographically independent molecules in the asymmetric unit, each hydrogen bonded via an oxygen atom to an ethanol adduct molecule; there are small but significant differences between the two molecules. The iron and cobalt complexes have a similar distorted trigonal-bipyramidal geometry.