Formation of a solvate of manganese(III) acetylacetonate with chloroform

Abstract

Metal acetylacetonates are coordination compounds consisting of the acetylacetonate anion (CH3COCHCOCH3, indicated as acac) and metal ions. Typically, both oxygen atoms of the anion bind with the metal and form a six-membered chelate ring. The simplest complexes have the formulas M(acac)3 and M(acac)2. Many complexes are soluble in organic solvents, and such solutions are used for the synthesis of catalysts. The processes of formation of solvates of acetylacetonates of various metals have not been studied properly. It should be noted that the determination of the composition and properties of solvates is important for understanding the peculiarities of the extraction processes of metal acetylacetonates.Manganese(III) acetylacetonate Mn(acac)3, for example, is also widely used. The recrystallisation of the complex is most commonly conducted from solutions in chloroform, and in this case, the corresponding solvates may be formed, which can affect the structure and properties of Mn(acac)3. There are no data on the synthesis conditions and the composition of the solvates of manganese(III) acetylacetonate with chloroform. Therefore, the purpose of this work is to study the possibilities of its formation and to establish the composition of such solvates. The formation of the solvate in solution was established using Fourier IR spectroscopy by the shift of the absorption band of the C-H chloroform bond. The composition of the Mn(acac)3· 2CHCl3 solvate was determined using gravimetric analysis.