INOR 156 |
| The synthesis, characterization, and hemithioacetal isomerization reactivity of a mononuclear Ni(II) deprotonated amide complex, [(bppppa–)Ni]ClO4·CH3OH (1, bppppa- = monoanion of N,N-bis-[(6-phenyl-2-pyridyl)methyl]-N-[(6-pivaloylamido-2-pyridyl)methyl]amine) is reported. Complex 1 was characterized by X-ray crystallography, 1H NMR, UV-vis, FTIR, and elemental analysis. Treatment of 1 with an equimolar amount of the hemithioacetal PhC(O)CH(OH)SCD3 in dry acetonitrile results in the production of the thioester PhCH(OH)C(O)SCD3 in ~60% yield. This reaction can be monitored by 2H NMR. Complex 1 is unreactive with the thioester product, PhCH(OH)C(O)SCD3, which indicates that the pKa value for the PhCH(OH)C(O)SCD3 proton of the thioester must be significantly higher than the pKa value of the C-H proton of the hemithioacetal (PhC(O)CH(OH)SCD3). A protonated analog of 1, [(bppppa)Ni](ClO4)2 (2), is unreactive with the hemithioacetal, thus indicating the requirement of the anionic chelate ligand in 1 for hemithioacetal isomerization reactivity. |
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Bioinorganic Modeling
7:00 PM-10:00 PM, Sunday, 10 September 2006 Moscone Center -- Hall D, Poster
Sci-Mix
Division of Inorganic Chemistry |