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Updated: Aug 8, 2026

Amide Coupling Reaction for the Synthesis of Bispyridine-based Ligands and Their Complexation to Platinum as Dinuclear Anticancer Agents
Published on: May 28, 2014
Linear Tricobalt Compounds with Di-(2-pyridyl)amide (dpa) Ligands: Studies of the Paramagnetic Compound
F. Albert Cotton1, Carlos A. Murillo, Xiaoping Wang
1The Laboratory for Molecular Structure and Bonding, Department of Chemistry, Texas A&M University, P.O. Box 30012, College Station, Texas 77842-3012, and Department of Chemistry, University of Costa Rica, Ciudad Universitaria, Costa Rica.
Abstract:
Solutions of Co(3)(dpa)(4)Cl(2), where dpa = di(2-pyridyl)amide ion, in CD(2)Cl(2) were studied by NMR in the temperature range 183-303 K. The spectra show only four (1)H and five (13)C resonance signals, consistent with the D(4) symmetry of the molecules found in the solid. The magnetic susceptibility in solution was determined by the Evans method from 193 to 308 K. These observations can be modeled as an S = 1/2 to S = 5/2 spin-transition process with DeltaH = 7.7(2) kJ mol(-1) and DeltaS = 20.8(8) J K(-1) mol(-1).
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