A new synthetic method to triammine complexes of Cr(III) is reported, via a hydrolytic process from tetrammine complexes. The crystal and molecular structure of 1 -chloro - 2,3 - diaquo - 4,5,6 - triamminchromium(III) chloride are described. The crystals are orthorombic, space group Pnma, with a = 13.230(2), b = 10.545(1), c = 6.754(1) Å, V = 942.3(3), Z = 4. Least-squares refinement of the structure based on 529 observations led to final discrepancy indices of R = 0.047 and Rw = 0.056. The Cr atom is bonded to two water molecules, three ammonia molecules and one chlorine atom in a distorted octahedral coordination showing a trans chloro-aquo configuration. © 1987.