Mn(III) complexes with asymmetrical N2O3 Schiff bases. The unusual crystalstructure of [Mn(phenglydisal-3-Br,5-Cl)(dmso)] (H(3)phenglydisal=3-aza-N-{2-[1-aza-2-(2-hydroxyphenyl)-vinyl]phenyl}-4-(2-hydroxyphenyl)but-3-enamide), a mononuclear single-stranded helical manganese(III) complex

Neutral manganese(III) complexes, with potentially pentadentate and trianio nic asymmetrical Schiff bases, containing a hard amido donor atom, have bee n synthesised. Complexes are found to be of the form Mn-III(phenglydisal-R) (H2O)(n)(n = 1- 4) [H(3)phenglydisal = 3-aza-N-{2-[1-aza-2-(2-hydroxyphenyl )vinyl]phenyl}-4-(2-hydroxyphenyl)but-3-enamide; R = H; 3-OEt, 4,6-(OMe)(2) , 5-NO2, 3-OMe, 5-Br, 3-Br,5-Cl] and have been characterised by elemental a nalyses, FAB mass spectrometry, IR and H-1 NMR spectroscopies, magnetic mea surements, molar conductivities and cyclic voltammetry. [Mn(phenglydisal-3- Br,5-Cl)(dmso)] 3, was also crystallographically characterised and its crys tal structure shows the manganese atom in an octahedral environment, with t he ligand giving rise to a mononuclear single-stranded helical complex.