Lithium complexes bearing mono-anionic aminophenolate ligands are described. Reactions of ligand precursors HONMePhOMe, HONMePhSMe, HONMeCOMe or HONMeCNMe2 [HONMePhOMe = (2-OMeC6H4CH2)N(Me)(CH2-2-HO-3,5-C6H2(tBu)2); HONMePhSMe= (2-SMe-C6H4CH2)N(Me)(CH2-2-HO-3,5-C6H2(tBu)2); HONMeCOMe = (MeOCH2CH2)N(Me)(CH2-2-HO-3,5-C6H2(tBu)2); HONMeCNMe2 = (Me2NCH2CH2)N(Me)(CH2-2-HO-3,5-C6H2(tBu)2)] with 1.1–1.3 molar equivalents of nBuLi in diethyl ether solution afford (LiONMePhOMe)2 (3), (LiONMePhSMe)2 (4), (LiONMeCOMe)2 (5) and (LiONMeCNMe2)2 (6) as dinuclear lithium complexes. The BnOH adduct of 5, (BnOH)(LiONMeCOMe) (7), was prepared from the reaction of 5 and BnOH in diethyl ether solution. The molecular structures are reported for ligand precursor HONMePhSMe and compounds 3–5 and 7. These dinuclear lithium complexes show excellent catalytic activities toward the ring-opening polymerization of L-lactide in the presence of benzyl alcohol.
