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The one-electron electroreduction of V2O3(L-Asal)2 in dichloromethane yields Et4N(V2O3(L-Asal)2). (L-Asal)2 is the deprotonated salicylaldimine of L-alanine, L-valine or L-phenylalanine. The metal atoms have a distorted square pyramidal geometry. The relative orientation of the two terminal V=O groups is intermediate between cis and trans. The unpaired electron is delocalized and thus the metal valence is over both metal atoms. The complex crystallizes in an orthorhombic space group.

The Mn(IV) oxide dimer of 1,3-bis(salicylideneamino)propane and the Mn(III) chloride dimer of methanolic 1-(salicylideneamino)-3-hydroxypropane complement 20 other oxide- and alkoxide-bridged manganese complex dimers in a correlation study between Mn-Mn separation and the Mn-O-Mn bridge angle. The study shows that mu-oxo bridges follow the law of cosine correlation while single-atom mu-alkoxo bridges do not. Despite deviations, the study manages to set an empirical correlation slope of 0.03 angstroms/degree within the 2.86-3.81 angstrom range. The implications of these findings in the behavior of multinuclear manganese enzymes are discussed.

Air oxidation of a solution of N,N'-bis(salicylidene)-1,3-diaminopropane (H2salpn), sodium hydroxide and manganese perchlorate hexahydrate, followed by ether treatment, yields the mononuclear Mn(salpn)(EtOH)2ClO4 complex. Slow cooling before ether treatment yields Mn(salpn)(EtOH)2(ClO4)-EtOH-H2O, which crystallizes into a triclinic form with two independent Mn(III) monomers per asymmetric unit. The bis(mu-oxo)dimanganese(IV) form results from further oxidation of the monomer in basic methanol or from air oxidation of Mn(salpn)(H2O) in pyridine. The structure and magnetic/electrochemical properties of these complexes are presented.

The synthesis, structure and zwitterion-transport properties of the crown-ether-functionalized (Mn(super t)Bu4salphen(H2O)(EtOH)18-crown-6)+Cl- complex are discussed. The molecule is part of a new, general class of hybrid (MR(sub eta)salphen-crown) complexes which combine the electron pair donor characteristics of the crown ether component with the metal-dependent electron pair properties of the Re(sub eta)salphen-bound metal ions.