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A series of mononuclear tantalum derivatives containing substituted pyrrole‐amine ligands are synthesized. Reacting TaCl5 with one equivalent of Li[C4H2N‐2,5‐(CH2NMe2)2] in toluene affords TaCl4[C4H2N‐2,5‐(CH2NMe2)2] (1), whereas TaCl4[C4H3N‐2‐(CH2NEt2)] (2) is generated between the combination of TaCl5 and Li[C4H3N‐2‐(CH2NEt2)] in moderate yield. Similarly, while subjecting Li[C4H2N‐2‐(CH2NMe2)‐5‐(CH2NHtBu)] with TaCl5 in diethyl ether, it affords TaCl3[C4H2N‐2‐(CH2NMe2)‐5‐(CH2NtBu)] (3) at moderate yield. Interestingly, the mixing of TaCl4[C4H2N‐2,5‐(CH2NMe2)2] (1) with excess Li[O‐Ph‐2,6‐iPr2] in tetrahydrofuran generates the tantalum aryloxide compound, Ta(O‐Ph‐2,6‐iPr2)Cl3[C4H2N‐2,5‐(CH2NMe2)2] (4). Single crystal X‐ray diffraction analysis reveals that compound 4 is hepta‐coordinated possessing a distorted pentagonal bipyramidal geometry. All the compounds are characterized by proton nuclear magnetic resonance and carbon‐13 nuclear magnetic resonance spectroscopy, and we highlight the structural variation of tantalum derivatives with bi‐ or tridentate (symmetric and asymmetric) pyrrole precursors.

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