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Updated: Jun 9, 2025

The Synthesis, Characterization and Reactivity of a Series of Ruthenium N-triphosPh Complexes
Published on: April 10, 2015
Structural Variety in Transition Metal Complexes of Tripodal Ligands Containing Mixed Quinolyl and Pyridyl Donors
Bronte Carr1, Timothy D Christopher2, Tilo Söhnel2,3
1Department of Chemistry, Auckland University of Technology, Private Bag 92006, Auckland, 1142, New Zealand.
Abstract:
The syntheses of the tripodal tetraamine ligands 2-(pyridin-2-yl)-N,N-bis(quinolin-2-ylmethyl)ethan-1-amine (DQPEA), N-(pyridin-2-ylmethyl)-2-(quinolin-2-yl)-N-(2-(quinolin-2-yl)ethyl)ethan-1-amine (DQEPMA), 2-(pyridin-2-yl)-N,N-bis(2-(quinolin-2-yl)ethyl)ethan-1-amine (DQEPEA), N,N-bis(pyridin-2-ylmethyl)-2-(quinolin-2-yl)ethan-1-amine (QEDPMA), and 2-(pyridin-2-yl)-N-(2-(pyridin-2-yl)ethyl)-N-(2-(quinolin-2-yl)ethyl)ethan-1-amine (QEDPEA) containing mixed quinolyl and pyridyl moieties are reported, with 2-vinylquinoline being used to attach quinolylethyl arms to the aliphatic N atom. X-ray crystal structures of [(Mn(DQPEA))2O2](ClO4)2 ⋅ (CH3CN)2, [Cu(DQPEA)NCCH3](ClO4)2, [Zn(DQPEA)NCCH3](ClO4)2, [Pd(DQEPEA)Cl]Cl ⋅ 11H2O are detailed, with four, five, and six-coordination observed. In addition, the dimeric complex [(DPEA)Co(μ-OH)3Co(DPEA)](ClO4)3 ⋅ 0.5H2O ⋅ MeCN containing the tridentate DPEA ligand formed by N-dealkylation of QEDPEA is reported. Calculations suggest that the very short Co…Co distance of 2.5946(6) Å in this complex is unlikely to be due to a Co-Co bond.
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