Synthesis of Molybdenum and Tantalum Complexes that Contain Diamido/Donor Ligands of the Type [(3,5-Cl2C6H3NCH2CH2)2NMe]2- or [(3,5-Cl2C6H3NCH2)2C(2-C5H4N)(CH3)]2-

The palladium-catalyzed reaction between diethylenetriamine and 2 equiv of 3,5-dichlorobromobenzene gave (3,5-Cl2C6H3NHCH2CH2)2NH. Methylation of the central nitrogen with methyl iodide gave (3,5-Cl2C6H3NHCH2CH2)2NMe (H2[ArClNNMe]). The palladium-catalyzed reaction between (H2NCH2)2C(2-C5H4N)(CH3) and 3,5-dichlorobromobenzene gave (3,5-Cl2C6H3HNCH2)2C(2-C5H4N)(CH3) (H2[ArClNpy]). Molybdenum compounds that were prepared include [Et3NH]{[ArClNNMe]MoCl3} (1a), [ArClNNMe]Mo(CCMe3)(CH2CMe3) (2), [ArClNNMe]MoCl(CH2R) [R = CMe3 (4a) or SiMe3 (4b)], [Et3NH]{[ArClNpy]MoCl3} (5), and Mo[ArClNpy]2 (6). Tantalum complexes that were prepared include [ArClNNMe]TaMe3 (7) and [ArClNpy]TaMe3 (8). X-ray studies of 1a, 4a, 6, and 7 are reported.