Metalat ions [Al(OR)4]- as chelating ligands for transition metal cations

Waterfree CoCl2 can be reacted with [{Li(Diglyme)}-Al((OBu)-Bu-t)(4)}] in THF to the complex [Li(THF)(4)][{CoCl2}{Al-(OtBu)(4)}]. Addition of diglyme to the reaction mixtures gives the bluecompound [Li(diglyme)(2)][{CoCl2} {AL(OtBu)(4)}] (1). According to this procedure the FeII complex [Li(Diglyme)(2)][{FeCl2}(2)-{Al((OBu4)-Bu-t}] (2) was formed by treatment of FeCl2 with Li[Al((OBu)-Bu-t)(4)]. [{Li(diglyme)}{Al((OBu)-Bu-t)(4)}] in THE/diglyme can be used as alkoxide transfer reagent on TiCl4 to give the neutral complex [TiCl2(OtBu)(2)(diglyme)] (3). The sky-blue salt [Li(THF)(4)](2)-[{CoCl2}(3){Al(OCH2Ph)(4)}(2)] (4) was obtained by reaction of Li[Al-(OCH2Ph)(4)1 with CoCl2 in THF. By treatment of 4 with diglyme ligand redistribution was observed giving the sky-blue compound [Li(Diglyme)(2)](2)[ {CoCl2}(3) {Al(OCH2Ph)(4)}(2)] (5) and the violet salt [Li(Diglyme)(2)](2)[Co2Cl5(OCH2Ph)] (6). A similar salt can be synthesized also directly from Li[Al((OBu)-Bu-t)(4)] and CoCl2 in diglyme to give [Li(Diglyme)(2)](2)[CO2Cl5((OBu)-Bu-t)] (7). 1-7 were characterized by IR spectroscopy, partly by mass spectrometry and X-ray analyses. UV-VIS spectra were recorded from 1 and 5. According to the X-ray analyses the M-II ions as well as the Al-III ions are coordinated distorted tedrahedrally. In 1 2, 4 und 5 the unit [Al(OR)4](-) acts a chelating ligand as desired.