AbstractsChemistry

Donor substituted group 14 anions introduce unique reactivity and electronic properties of the corresponding metal complex. Zwitterionic metal complexes are rare species where the anionic center is rigidly locked and charge-separated by the internal bridges. The lone pair of electrons on the anionic center provides additional coordination ability. In this dissertation, zwitterions E(SiMe2OCH2CH2DMe)3M ( E = C, Si, Ge; D = O, N, S; M = Li, Na, K) were prepared and characterized by nuclear magnetic resonance (NMR) and X-ray diffraction. The metal silanides show dual reactivity: 1) the metal cation can undergo metal metathesis to form a new metal complex, 2) the lone pair of the silyl anion was used to synthesize hetero bimetallic complexes. The carboanions were used as Lewis base in frustrated Lewis pair (FLP) chemistry to cleave H2 in concert with weak Lewis acids. To further understand the reactivity and charge separation in these zwitterions, relative basicities of the anionic centers were experimentally determined. Gas phase basicities (GPB) and natural population analysis (NPA) charges were generated by density functional theory (DFT) calculation. The impact of metal cation and donor groups were also discussed.