Synthesis and crystal structures of beta-[Be(DMF)(4)]I-2, [Be(Pyr)(4)]I-2, [Be(NMP)(4)]I-2 and [BeI2(Lut)(2)]

摘要

Four solvent complexes of beryllium iodide were prepared by dissolving BeI2 in N,N-dimethyl formamide (DMF), pyridine (Pyr), N-methyl pyrrolidone (NMP) and 2,6-dimethyl pyridine (2,6-lutidine, Lut). Their crystal structures were established from single crystal X-ray diffraction. For [Be(DMF)(4)]I-2 a new modification is reported (monoclinic, space group P2(1)/c, a = 12.491(2), b = 11.593(2), c = 15.310(3) angstrom, beta = 94.7073(6)degrees). In [Be(Pyr)(4)]I-2 (monoclinic, space group C2/c, a = 17.8799(13), b = 7.6174(5), c = 18.2611(14) angstrom, beta = 113.508(4)degrees) and [Be(NMP)(4)]I-2 (orthorhombic, space group Pbca, a = 13.941(5), b = 15.754(3), c = 24.634(7) angstrom) homoleptic tetrahedral complex cations are formed, while the sterically demanding solvent ligand Lut yields a neutral complex with covalently bound iodine ligands [BeI2(Lut)(2)] (monoclinic, space group P2(1)/c, a = 7.8492(9), b = 24.265(3), c = 27.037(3) angstrom, beta = 97.076(3)degrees). Their electrochemical stability with respect to their application as beryllium electrolytes for deposition of beryllium from solution is discussed.