Oxidatively induced B-to-Pt and Pt-to-B hydrocarbyl transfer involving CH agostic Pt(IV) dihydrocarbyldipyridylborates

INOR 372

Eugene Khaskin, ekhaskin@umd.edu, Peter Y. Zavalij, and Andrei N. Vedernikov, avederni@umd.edu. Department of Chemistry and Biochemistry, University of Maryland, Chemistry Building, College Park, MD 20742
We found that oxidation of dialkyl and diaryl Pt(II) dimethyldipyridylborates R2PtII(η2-Me2BPy2) (R = Me, Ph) in hydroxylic solvents R'OH (R' = H, Me, Et) by oxygen from air, leads to clean boron-to-platinum methyl transfer and formation of oxomethyldipyridylborato trihydrocarbyl Pt(IV) complexes R2MePtIV[η3-(R'O)B(Me)Py2]. Similar products were obtained when alkyl halides were used. When oxidation was performed with methyl iodide in aprotic solvents, intermediate CH agostic Pt(IV) trihydrocarbyl complexes R2MePtIV(Me2BPy2) could be isolated. It was shown that for R = Ph the hydrocarbyl transfer in the opposite direction, from Pt to B, is possible. Isotopic labeling experiments and DFT calculations were used to shed light on the nature of hydrocarbyl transfer step. The mechanism and possible synthetic applications of these reactions will be discussed.
 

General Organometallic Chemistry
9:00 AM-12:20 PM, Monday, August 20, 2007 BCEC -- 211, Oral

Division of Inorganic Chemistry

The 234th ACS National Meeting, Boston, MA, August 19-23, 2007