The reaction of an aromatic heterocycle with a proton is called a protonation. One of articles about this theory is 《Molecular association and electronic structures of Ni(II) chelates. I. Complexes of pentane-2,4-dione and some 1,5-di-substituted derivatives》. Authors are Cotton, F. A.; Fackler, J. P. jr..The article about the compound:Bis(2,2,6,6-tetramethyl-3,5-heptanedionato)nickel(II)cas:14481-08-4,SMILESS:CC(C)(C1=O[Ni+2]2(O=C(C(C)(C)C)[CH-]1)O=C([CH-]C(C(C)(C)C)=O2)C(C)(C)C)C).COA of Formula: C22H38NiO4. Through the article, more information about this compound (cas:14481-08-4) is conveyed.
The anomalous magnetic and spectral behavior of some planar Ni(II) complexes, under certain conditions, is due to the mol. association of the solute mol. in solvents of low coordinating power. The magnetic moment and spectrum of bis(2,6-dimethyl-3,5-heptanediono)Ni(II) dissolved in toluene depend on both temperature and concentration Spectral and magnetic data at 0-50° and 0.24-0.010M are presented with the thermodynamic parameters of the association process. The more highly hindered bis(2,2,6,6-tetramethyl-3,5-heptanediono)Ni(II) remains diamagnetic under all conditions. Bis(2,4-pentanediono)-Ni(II) is associated in noncoordinating solvents at ordinary temperature, with significant concentrations of red monomer occurring only at ∼200°. Structures for the polymeric species are considered. Ni(OAc)2.4H2O (1.5 g.) was dissolved in 10 ml. absolute MeOH and the solution added to 5 ml. of MeOH containing a slight excess of freshly distilled 2,6-dimethyl-3,5-heptanedione; 5 ml. of H2O was added, the product was removed by filtration, and vacuum dried at 100° over P2O5. The product was recrystallized from C2H4Cl2, sublimed in vacuo at 150° to give bis(2,6-dimethyl-3,5-heptanediono)Ni(II), m. 155° (sealed tube). Bis(2,2,6,6-tetramethyl-3,5-heptanediono) Ni(II), m. 217-21°, was prepared similarly.
In addition to the literature in the link below, there is a lot of literature about this compound(Bis(2,2,6,6-tetramethyl-3,5-heptanedionato)nickel(II))COA of Formula: C22H38NiO4, illustrating the importance and wide applicability of this compound(14481-08-4).
Reference:
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