Complexes of 2-aminobenzothiazole with cobalt(II) and nickel(II)

Abstract

Electronic and far-i.r. (400–80 cm.^–1) spectral data indicate that complexes of 2-aminobenzothiazole (abt) of the types M(abt)₂X₂(M = Co, X = Cl, Br, I, or NCS; M = Ni, X = Br) and [Et₄N][M(abt)X₃](M = Co, X = Cl, Br, or I; M = Ni, X = Cl or Br) are pseudotetrahedral. In complexes M(abt)₂X₂(M = Co or Ni, X = OAc or NO₃) the metal is in a six-co-ordinated environment as it is in Ni(abt)Cl₂·2H₂O. The 3 : 1 cobalt perchlorate complex is pseudotetrahedral and is formulated as [Co(abt)₃ClO₄]ClO₄. Ni(abt)₂X₂ exist as both blue pseudotetrahedral and yellow tetragonal isomers when X = Cl and as a planar complex when X = I. Except for the yellow form of Ni(abt)₂Cl₂ in which the donor centre appears to be the amino-group, co-ordination takes place through the ring nitrogen atom.