Some substituted urea and thiourea complexes of Co(II), Mn(II), and Cr(III)

Complexes of Co(II), Mn(II), and Cr(III) with N-butylurea, N-methylthiourea, and N,N′-dimethylthiourea, and Cl − , Br − , NO 3 − , and ClO 4 − anions were prepared and characterized using infrared and visible spectroscopy, and magnetic susceptibility. The urea is bonded through oxygen, and the thioureas through sulfur in all cases. The Co–N-butylurea compounds are octahedral, mostly with CoL 6 X 2 stoichiometries, but some compounds involving coordinated anions and possibly bridging butylurea ligands were found. The Co–thioureas are tetrahedral. Octahedral Cr(III) compounds of the type CrL 3 X 3 and CrL 6 (ClO 4 ) 3 were prepared, and the CrS 6 chromophore characterized. Mn(II)–butylureas are octahedral, while the thioureas show MnL 6 X 2 and MnL 4 X 2 stoichiometries. X-ray diffraction established some of the latter to be isostructural with the analogous tetrahedral Co(II) compounds. Ligand field parameters Dq and B have been evaluated for the Co(II) and Cr(III) compounds.