BINOL Compounds of Group 13

2001-05-04T00:00:00Z (GMT) by Soheila Chitsaz Bernhard Neumüller
The reaction of GaMe3 with 1 equiv of (S)-BINOL ((S)-(−)-2,2‘-dihydroxy-1,1‘-binaphthyl) in toluene at reflux conditions gave after recrystallization from THF the chiral organogallium alkoxide [(THF)MeGa((S)-BINOLate)]2 (1). In contrast treatment of PhCH2InCl2 with 1 equiv of Li2((S)-BINOLate) in THF at reflux and recrystallization from DME led not to the desired organoindium alkoxide but to [{(DME)Li}3{In((S)-BINOLate)3}]·2DME (2·2DME). The similar salt [{(DME)Li}3{In((S)-BINOLate)3}]·0.75THF (2·0.75THF) was obtained by direct synthesis of InCl3 with 3 equiv of Li2((S)-BINOLate) in THF at 65 °C and recrystallization from DME. The compounds 1 and 2 are readily soluble only in donor solvents, while the potassium derivative [{(toluene)2K}3{In((S)-BINOLate)3}]·2toluene (3·2toluene), obtained in the reaction of InCl3 with 3 equiv of K2((S)-BINOLate) in toluene, is very soluble in toluene and n-hexane. 13 have been characterized by their NMR, IR, and MS spectra as well as by X-ray analyses. Compound 1 is dimeric with a Ga2O2 four-membered ring. 2 consists of a tetranuclear InO6Li3 skeleton in which every Li+ ion is coordinated by one additional DME ligand. The basic structural motif in 3, an InO6K3 core, is comparable to the skeleton in 2. However, the coordinated toluene molecules of every K+ ion in 3 are bound by mainly electrostatic metal−π-electron interactions.