New synthetic methods for unsymmetrical and chiral polyoxometalate complexes using transferable subunits and linkers

Three new synthetic routes were developed and investigated during this research: (1) Exchange reactions as a means of assembling new polyoxometalates from preformed labile complexes as a source of unstable building units; (2) Transmetallation processes to introduce organotin groups into plenary polyoxometalates and the use of the di-tin precursor alpha, omega-bis(trichlorostannyl)butane to covalently link two or more polyoxometalate moieties; (3) Incorporation of chelated Co(III) heteroatoms in polyoxometalate anions.; Several new polyoxometalates have been synthesized and characterized using these three new synthetic routes. The kinetic stability of the pentatungstate anion (lacunary derivative of the Lindqvist structure) was proven using exchange reactions between Peacock-Weakley type anions, and a substitution reaction between methyltin trichloride and decatungstocerate resulted in organotin substituted pentatungstate complex in aqueous media.; A family of organotin substituted chiral sandwich-type complexes with methyltin, ethyltin, and butyltin groups were isolated and structurally characterized. A di-organotin linker was used to connect two undecatungstosilicates to form a dumbbell-shaped anion and to link several of the sandwich-type complexes to yield linear polyelectrolytes.; The first examples of polyoxometalates incorporating chelated heteroatoms have been prepared with ethylenediaminecobalt(III) center. These complexes open the door to robust polyoxometalate structure with new potentially chiral frameworks.