ISSN print edition: 0366-6352 ISSN electronic edition: 1336-9075 Registr. No.: MK SR 9/7 Published monthly

Preparation and the Standard Enthalpy of Formation of 2-Amino-4,6-dimethoxypyrimidine and the Related Complexes of Copper

W. Qing, Y. Xuwu, G. Shengli, and S. Qizhen

Shaanxi Key Laboratory of Physico-Inorganic Chemistry, Department of Chemistry, Northwest University, Xi’an Shaanxi 710069, P. R. China

E-mail: weizhang@nwu.edu.cn

Received: 8 March 2002

Abstract: The complexes of hydrous copper chloride and copper nitrate with 2-amino-4,6-dimethoxypyrimidine (AMP) in the mole ratio of 1:2 were prepared through reflux in alcohol. The compositions of the complexes Cu(AMP)₂Cl₂ and Cu(AMP)₂(NO₃)₂ were determined by chemical and elemental analyses. The bonds between Cu²⁺ and AMP were investigated by IR, XPS, ¹H NMR and the structures of the complexes were presumed. The constant-volume combustion energies of the ligand and the complexes, Δ_cE, were determined by a precise rotating bomb calorimeter at 298.15 K. They were (−3340.01 ± 1.54) kJ mol⁻¹, (−5684.22 ± 2.24) kJ mol⁻¹, and (−6526.47 ± 4.59) kJ mol⁻¹. Their standard enthalpies of combustion, Δ_cH⁰_m , and standard enthalpies of formation, Δ_fH⁰_m , were calculated. They were (−3339.39 ± 1.54) kJ mol⁻¹, (−5678.02 ± 2.24) kJ mol⁻¹, (−6516.55 ± 4.59) kJ mol⁻¹ and (−307.91 ± 1.74) kJ mol⁻¹, (−1670.59 ± 2.73) kJ mol⁻¹, (−933.27 ± 4.85) kJ mol⁻¹.

Full paper in Portable Document Format: 572a97.pdf

Chemical Papers 57 (2) 97–101 (2003)