Isomers of aminopropanol react with Cu[CF₃SO₃]₂ to form compounds of the general formula [Cu₂(RS-ap)₂(RS-Hap)₂][CF₃SO₃]₂, [Cu₂(S-ap)₂(S-Hap)₂][CF₃SO₃]₂, [Cu₃(RS-pa)₂(RS-Hap)₆][CF₃SO₃]₄, and [Cu₂(S-pa)(S-Hpa)₅][CF₃SO₃]₃, where RS-Hap and S-Hap represent R,S- and S(+)-1-aminopropan-2-ol, respectively, and RS-Hpa and S-Hpa represent R,S- and S(+)-2-aminopropan-1 -ol; RS-ap, S-ap, RS-pa, and S-pa are the respective anions formed by ionisation of the acidic alcohol proton of the isomers. The structure of [Cu₃(RS-pa)₂(RS-Hpa)₆][CF₃SO₃]₄ has been determined by X-Ray crystallography. The compound crystallizes in space group P1 with unit-cell dimensions a= 10.345(2), b= 10.720(2), c= 13.619(2)Å, α= 80.40(2), β= 71.41(2), γ= 85.14(2)°, and Z= 1. The structure was solved by Patterson methods and least-squares refinement converged at R 0.046 and R′0.046. The structure consists of unique O ⋯ H ⋯ O hydrogen-bonded trinuclear units. The central copper atom (C) has a tetragonal co-ordination and is linked to the other two copper atoms via two short oxygen–oxygen distances of 2.43(2) and 2.37(2)A. Copper atoms A and B are octahedrally co-ordinated by three chelating ligands and have the configurations Δ(δλλλ)[or Δ(λδδ)] and Δ(δδδ)[or Δ(λλλ)], respectively. The geometry of the CuN₃O₃ species for A and B is meridional. The magnetic behaviour of the four compounds is discussed. The magnitude of the magnetic exchange (J) is about –5 cm^–1 for the dimeric 1-aminopropan-2-ol compounds. The J values for the trinuclear R,S-2-aminopropan-1 -ol compound and the dimeric S(+)-2-aminopropan-1 -ol compound are calculated to be +0.06 and –8.5 cm^–1, respectively. The magnitude of the magnetic exchange in these compounds has been related to the co-ordination geometry around the copper ions.