Crystal and molecular structures of the acetylacetonate derivatives [Se(CH3C(O)CC(O)CH3)]2 and [PhSe]2[CH3C(O)CC(O)CH3]

Abstract

All attemps to synthesise SeIV derivatives of acetylacetone resulted in the formation of SeII complexes with the selenium atom coordinated to the methine carbon atom of the ligand. The crystal structure of [Se(acac)]2 (where acac = CH3C(O)CC(O)CH3) shows a SeSe separation of 2.9007(4) Å. [PhSe]2[acac] contains two independent molecules within the unit cell and steric restrains are less severe, so that the SeSe separation is approximately 3.34 Å. Crystals of [Se(acac)]2 are monoclinic, space group P21/c with Z = 2, a 6.9979(9), b 7.881(2), c 10.843(2) Å and β 94.26(1)°. Crystals of [PhSe]2[acac] are triclinic, space group P 1 -, with Z = 4, a 9.796(2), b 10.675(1), c 17.162(2) Å, α 73.504(9),..