Some observations on the structures of pyridoxal-aminoacid schiff base complexes

Abstract Structures are reported for (pyridoxylidene-DL-valinato)copper(II), a = 25.640(2), c = 13.326(2) A , γ = 120°, space group R 3 , Z = 8 and (3-methoxysalicylidene-DL-valinato)copper(II), a = 23.515(8), b = 9.194(4), c = 17.034(6) A , β = 126.41(7)°, space group C2/c, Z = 8. The former compound is polymeric with square-pyramidal co-ordination to copper involving five donor atoms of the ligand; the latter is monomeric with planar co-ordination geometry which includes a donor oxygen from water. Attention is drawn to bond length changes in the pyridoxylidene compound which, it is suggested, can be associated with reactivity.