Crystal Structure of TaCl(NMe₂)₄ and Its Reactions with Lithium Amides and Water. Indirect Observation of an Equilibrium among TaCl(NMe₂)₄, Ta(NMe₂)₅ and Ta₂(μ-Cl)₂(NMe₂)₆Cl₂

Reactions of TaCl(NMe2)4 (2) with LiNR2 (R = SiMe3, Et), yielding Ta(NMe2)4(NR2) (R = SiMe3, 4; Et, 7), Ta(NMe2)5 (1), (Me2N)3TaN(SiMe3)SiMe2CH2 (5), and Ta(NMe2)3(NEt2)2 (8), respectively, suggest the presence of an equilibrium among TaCl(NMe2)4 (2), Ta(NMe2)5 (1), and Ta2(μ-Cl)2(NMe2)6Cl2 (3): 2 2 ⇌ 1 + 0.5 3. New products Ta(NMe2)4(NR2) have been characterized. Ta(NMe2)4(NEt2) (7), Ta(NMe2)5 (1), and Ta(NMe2)3(NEt2)2 (8) are in a slow exchange: 2 7 ⇌ 1 + 8 with an equilibrium constant of Keq = 0.25(0.01) at 90 °C. The following are also reported: X-ray crystal structure and a one-step synthesis of TaCl(NMe2)4 (2), reaction of 2 with H2O giving Ta2(μ-Cl)2(μ-O)(NMe2)6 (9), X-ray structure of 9, and preparation of LiNEt2 solid.