Chromium(II) chemistry. Part VIII. Complexes of 1,3-diaminopropane and some carbon- and nitrogen-substituted ethylenediamines

Abstract

The new chromium(II) complexes of 1,2-diaminopropane (pn) : Cr(pn)₃Cl₂,2H₂O,Cr(pn)₃Br₂,H₂O, and Cr(pn)₃I₂; of 1,3-diaminopropane (dap): Cr(dap)₂X₂(X = Cl, Br, or I); of 1,2-diamino-2-methylpropane (dmp) : Cr(dmp)₂X₂; and of NN-dimethylethylenediamine (NN dmn) or NN′-dimethylethylenediamine (NN′ dmn); Cr(NN dmn)₂Br₂, Cr(NN dmn)₂I₂, and Cr(NN′ dmn)₂Cl₂ have been found to be high-spin with temperature-independent magnetic moments of ca. 4·8 BM. Reflectance spectra show that the 1,2-diaminopropane complexes have distorted octahedral structures in spite of the presence of six equivalent donor atoms. No bis(amine) complexes of 1,2-diaminopropane, or tris(amine) complexes of the other amines, could be isolated. The bis(amine) complexes are assigned trans-octahedral structures with co-ordinated anions. The complexes CrLX₂(L = 1,3-diamino- or 1,2-diamino-2-methyl-propane) have also been isolated, and from their antiferromagnetic behaviour and spectra are assigned chloride-bridged polymeric structures.