Three polyhydroxyl-bridged tetranuclear Mn III complexes [Mn 4 (L 1a ) 2 (µ 3 -OMe) 2 (µ 2 -OMe) 2 (MeOH) 2 ] (1), [Mn 4 (L 2a ) 2 (µ 3 -OMe) 2 (µ 2 -OMe) 2 (H 2 O) 2 ] (2), and [Mn 4 (L 3a ) 2 (µ 3 -OMe) 2 (µ 2 -OMe) 2 (H 2 O) 2 ] (3) derived from Mn n+ -promoted reactivity of Schiff base ligands (HL 1 = 1-(4-{[(E)-3,5-dichlorine-2-hydroxybenzylidene]amino}phenyl)ethanone O-benzyloxime,have been synthesized and characterized. In the Mn III complexes 1, 2, and 3, the newly formed ligands (L 1a ) 4− , (L 2a ) 4− , and (L 3a ) 4− are derived from the chemoselective cleavage of the C=N bond in the original Schiff base ligands HL 1 , HL 2 , and HL 3 to form corresponding halogenated salicylaldehyde, 3,5-dichlorosalicylaldehyde, 3-bromine-5-chlorosalicylaldehyde, and 3,5-dibrominesalicylaldehyde, respectively. Then, the further addition of acetone to two halogenated salicylaldehyde molecules in situ α,α double aldol reaction promoted by Mn n+ ions in the presence of base to give the new ligands ((L na ) 4− . X-ray crystallographic analyses of the Mn III complexes 1, 2, and 3 show that the three complexes are all tetranuclear structure and crystallizes in the triclinic system, space group P-1. The four Mn III ions and bridging alkoxido groups are arranged in a face-shared dicubane-like core with two missing vertices. In the three Mn III complexes, the asymmetric unit contains two kinds of different Mn III ions (Mn1 and Mn2), where the Mn III ions are all hexacoordinated with slightly distorted octahedral geometries. Simultaneously in the synthesis of multinuclear Mn n+ complexes above, we explored the crystal structure, spatial configuration, and spectroscopic properties of the multinuclear Mn III complexes with different halogen substituents. favorable reaction will allow to obtaining ligands that are extremely difficult to separate by classical anionic organic chemistry under conventional conditions. This, in turn, will allow the synthesis of novel-innovative metal complexes that are pre-restricted by ligand design [8][9][10][11][12][13][14][15][16][17]. Based on this, the transition metal Mn ion has become our target of choice due to its various oxidation states and Lewis acidity [18], which acts as a potential promoter to study the extent of the in situ aldol reaction of acetone and salicylaldehyde derivatives. Up to now, the use of Mn ions for the synthesis of aldol products has been relatively little explored, as reported, a unique one-pot α,α-double aldol addition of acetone to two o-vanillin molecules promoted by Mn n+ ions in situ, leading to a novel multidentate ligand, further obtained a rare defect-dicubane {Mn 4 } complex [19]. Therefore, we hope that we can synthesize a variety of multinuclear Mn complexes, explore the spatial structure and crystal parameters, and perhaps determine the laws.Moreover Schiff base ligands and their complexes have been application in many fields [20][21][22][23], such as biological activity reagents [24][25][26][27][28][29][30][31][32][33][34], magnetic materials [35][36][37]...