METALLO-ORGANIC COMPOUNDS CONTAINING METAL–NITROGEN BONDS: PART III. DIALKYLAMINO COMPOUNDS OF TANTALUM

Abstract

Reactions involving TaCl5 and LiX (where X = NMe2, NEt2, NPr2n, NBu2n, NMeBun, and NC5H10) were shown to produce substantially the pentaderivatives TaX5. The thermal decomposition of TaX5 (X = NMe2, NEt2, NPr2n, NBu2n, and NMeBun) was studied and only Ta(NMe2)5 could be sublimed unchanged. In other cases the main product of decomposition was a quinquevalent compound RN=Ta(NR2)3 and the secondary amine R2NH. Some olefin and quadrivalent Ta(NR2)4 were also detected and it is believed that decomposition involves the following sequence:[Formula: see text]This is in contrast to the behavior of niobium compounds, which appears to be:[Formula: see text]