| Summary: | Thesis (Ph.D.)--Memorial University of Newfoundland, 1999. Chemistry Bibliography: leaves 236-258. Although chirality can arise in various guises in organometallic systems, metal centered chirality has become an ever growing concern due to its potential high efficiency in asymmetric synthesis. This thesis focuses on the synthesis, structure and properties of some chiral-at-metal transition metal organometallics. -- Reactions of CpCo(X)(Y)(I) (X=(5)-Ph2PNHCH(Me)Ph, Y=I, CF3; XY=PhCH(Me>-N=CH-C4H3N) with EtjNPCOMe^ toward diastereoselective synthesis of novel Co-and P-chiral amidophosphonate Co(LLI) complexes were studied by a combination of lH, 13C, l9F, 3IP NMR, proton NOED, CD spectroscopy and single crystal X-ray diffraction in order to rationalize the Co*-P chiral induction and to establish the solid-state structure, configuration and solid-state/solution conformations. The results show that chemical outcome varies from one system to another. -- Study on reaction of a series of resolved chiral aminophosphine Co(HI) complexes (CpCo(I)(P(0)(R)(OMe))(Ph2NHCH(Me)Ph)) with gaseous HCl shows that the reaction affords regioselective P-N bond cleavage products with retention of configuration at Co* and establishes a convenient method to obtain homochiral transition metal complexes. The regioselectivity was discussed based on EHMO calculations. lH NMR evidence for the formation of isobutene, resulting from P-C bond activation via ^-elimination in a diastereoselctive, Arbuzov dealkylation reaction involving dimethyl f-butylphosphite, was found. -- A series of new chiral-at-metal and non-chiral titanocene derivatives with general formula CpCC^TiQCXAr) (R=Me, X=C1, Ar=C6F5, o-FC6H4; R=H, X=C1, Ar=C6F3> o-FC6H4; R=H, X-Ar=C^F5chFC6U^ was synthesized and characterized. The barrier of aryl rotation around Ti-C^0 and the possibility of coordination of ortho~F to Ti were examined by variable temperature NMR, MMX and EHMO methods, as well as solid state single crystal X-ray diffraction.
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