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Published on: March 6, 2013
High-oxidation-state neutral and cationic tantalum(IV) alkyl complexes that are stable toward beta-hydrogen and
Albert Epshteyn1, Peter Y Zavalij, Lawrence R Sita
1Department of Chemistry and Biochemistry, University of Maryland, College Park, Maryland 20742, USA.
Abstract:
The synthesis and solid-state structural characterization of a family of homoleptic and mixed dialkyl d1Ta(IV) complexes of the formula, (eta5-C5Me5)TaR1R2[N(i-Pr)C(Me)N(i-Pr)], where R1 = R2 = i-Bu (3), n-Bu (4), and Et (7), and R1 = Me, R2 = i-Bu (10), neopentyl (Np) (11), are reported, along with those for the cationic d1Ta(IV) complex, {(eta5-C5Me5)TaNp[N(i-Pr)C(Me)N(i-Pr)]}[B(C6F5)4] (12). All of the new compounds displayed a remarkably high degree of solution stability toward beta-hydrogen and beta-methyl eliminations/abstractions. Thermolysis of 3 in toluene at 80 degrees C for 18 h provided the Ta(IV) trimethylenemethane (TMM) complex 13.
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