219598-52-4Relevant academic research and scientific papers
Synthesis of triamidoamine ligands of the type (arylNHCH2CH2)3N and molybdenum and tungsten complexes that contain an [(arylNCH2CH2)3N]3-ligand
Greco,Schrock
, p. 3850 - 3860 (2008/10/08)
Aryl bromides react with (H2NCH2CH2)3N in a reaction catalyzed by Pd2(dba)3 in the presence of BINAP and NaO-t-Bu to give the arylated derivatives (ArylNHCH2CH2)3N [Aryl = C6H5 (1a), 4-FC6H4 (1b), 4-t-BuC6H4 (1c), 3,5-Me2C6H3 (1d), 3,5-Ph2C6H3 (1e), 3,5-(4-t-BuC6H4)2C6H3 (1f), 2-MeC6H4 (1g), 2,4,6-Me3C6H2 (1h)]. Reactions between (ArNHCH2CH2)3N (Ar = C6H5, 4-FC6H4, 3,5-Me2C6H3, and 3,5-Ph2C6H3) and Mo(NMe2)4 in toluene at 70 °C lead to [(ArNHCH2CH2)3N]Mo(NMe2) complexes in yields ranging from 64 to 96%. Dimethylamido species (Ar = 4-FC6H4, 3,5-Me2C6H3) could be converted into paramagnetic [(ArNHCH2CH2)3N]-MoCl species by treating them with 2,6-lutidinium chloride in tetrahydrofuran (THF). The direct reaction between 1a-f and MoCl4(THF)2 in THF followed by 3 equiv of MeMgCl yielded [(ArNHCH2CH2)3N]MoCl species (3a-f) in high yield. If 4 equiv of LiMe instead of MeMgCl are employed in the direct reaction, then [(ArNHCH2CH2)3N]MoMe species are formed. Tungsten species, [(ArNHCH2CH2)3N]WCl, could be prepared by analogous direct methods. Cyclic voltammetric studies reveal that MoCl complexes become more difficult to reduce as the electron donating ability of the [(ArNHCH2CH2)3N]3- ligand increases, and the reductions become less reversible, consistent with ready loss of chloride from {[(ArNHCH2CH2)3N]MoCl}-. Tungsten complexes are more difficult to reduce, and reductions are irreversible on the CV time scale.
Synthesis of aryl-substituted triamidoamine ligands and molybdenum(IV) complexes that contain them
Greco, George E.,Popa, Alexandru I.,Schrock, Richard R.
, p. 5591 - 5593 (2008/10/08)
Compounds of the type [(ArNHCH2CH2)3N] (Ar = phenyl (H3[1a]), 4-fluorophenyl (H3[1b]), 4-tertbutylphenyl (H3[1c]), 3,5-dimethylphenyl (H3[1d]), 2-methylphenyl (H3[1e]), and mesityl (H3[1f])) have been synthesized by the Pd-catalyzed coupling of (H2NCH2CH2)3N with aryl bromides. Molybdenum methyl complexes containing [1a-d]3- can be prepared by adding 4 equiv of methyllithium to a mixture of the ligand and MoCl4(THF)2; the corresponding chloride complexes are obtained upon addition of 2,6-lutidinium chloride to the methyl complexes. . Copyright 1998 American Chemical Society.
