I. Yoshida, H. Kobayashi, K. Ueno
May 1, 1972
Citations
0
Influential Citations
16
Citations
Journal
Bulletin of the Chemical Society of Japan
Abstract
Bis(heptane-3,5-dionato)nickel(II) monohydrate [Ni(DNPM)2·H2O], bis(nonane-4,6-dionato)nickel(II) monohydrate [Ni(DNBM)2·H2O], bis(2,6-dimethylheptane-3,5-dionato)nickel(II) monohydrate [Ni(DIBM)2·H2O], bis(2,8-dimethylnonane-4,6-dionato)nickel(II) monohydrate [Ni(DIVM)2·H2O] and bis(tridecane-6,8-dionato)nickel(II) monohydrate [Ni(DNCM)2·H2O] were prepared, and a dimeric octahedral structure was proposed for each of them by means of spectroscopic studies. These dimeric chelates, (NiL2·H2O)2 were stable in solid state, however they disproportionated in non-coordinating solvents to afford dimeric monohydrates, Ni2L4·H2O, and monomeric dihydrates, NiL2·2H2O. DTA studies show that these monohydrates dehydrate in two steps and that the temperature of dehydration decreases in the order of the ligands, DNPM, DNBM, DIBM, DIVM, and DNCM. The dehydrated chelates are green in the neighborhood of room temperature while they changed into red at an elevated temperature. This thermochromism indicates that the chelates ...