950892-48-5Relevant academic research and scientific papers
Carbon dioxide activation by "Non-nucleophilic" lead alkoxides
Tam, Eric C.Y.,Johnstone, Nick C.,Ferro, Lorenzo,Hitchcock, Peter B.,Fulton, J. Robin
, p. 8971 - 8976 (2009/12/25)
A series of terminal lead alkoxides have been synthesized utilizing the bulky β-diketiminate ligand [{N(2,6-iPr2C 6H3)-C(Me)}2CH]- (BDI). The nucleophilicities of these alkoxides have been examined, and unexpected trends were observed. For instance, (BDI)PbOR reacts with methyl iodide only under forcing conditions yet reacts readily, but reversibly, with carbon dioxide. The degree of reversibility is strongly dependent upon minor changes in the R group. For instance, when R = isopropyl, the reversibility is only observed when the resulting alkyl carbonate is treated with other heterocumulenes; however, when R = tert-butyl, the reversibility is apparent upon any application of reduced pressure to the corresponding alkyl carbonate. The differences in the reversibility of carbon dioxide insertion are attributed to the ground-state energy differences of lead alkoxides. The mechanism of carbon dioxide insertion is discussed.
