By reaction of N-benzoyl-N′-(p-nitro/p-bromphenyl)thioureas with copper(II)acetate-monohydrate in methanole insoluble copper(I)precipitates have been obtained, from which filtrates bis[N-benzoyl-O-methyl-N′-(p-nitrophenyl)-isoureato]copper(II) 1 and bis[N-benzoyl-O-methyl-(p-bromphenyl)-isoureato]copper(II) 2 were isolated. The moleculare structure of 1 with planar trans coordination has been determined by single crystal X-ray diffraction methods. The N-benzoyl-O-methyl- N′-(o-nitrophenyl)-isourea 3 and N-benzoyl-O-methyl-N′-(p-bromphenyl)-isourea 4 have been prepared by reaction of the corresponding N-benzoyl-N′-phenyl-thioureas with mercury(II)acetate in methanolic solution. The molecular structure of 3 has been determined by single crystal X-ray diffraction methods. The NH-tautomeric form is stabilized by a bifurcated intramolecular hydrogen bond to an oxygen atom of the o-nitro group and the benzoyl oxygen atom. XPS, NMR and mass-spectrometric investigations also confirm the structures. © Johann Ambrosius Barth 1998.