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Complexes containing aminophenolate ligands are considered as very efficient initiators of ring-opening polymerization (ROP). Our systematic studies of the reactions of two selected aminophenols, 2-[( p-tolylamino)methyl]-4-(2,4,4-trimethylpentan-2-yl)phenol (L'H2) and 2-cyclohexylaminomethyl-4-methylphenol (L″H2), with alkyl compounds of aluminium, gallium and zinc resulted in the formation of a variety of products depending on the type of metallic centre and alkyl groups bonded to metal atoms. New trinuclear aluminium complexes (Me5Al3(L′)2 ( 1) and Me5Al3(L″)2 ( 2)), monomeric aluminium ( tBu2Al(L'H) ( 3) and tBu2Al(L″H) ( 5)) and gallium ( tBu2Ga(L'H) ( 4) and tBu2Ga(L″H) ( 6)) compounds, and dinuclear gallium (Et2Ga(L″H)·Et3Ga ( 7)) and zinc ( tBuZn(L″H)]2 ( 8)) complexes were isolated and characterized. The molecular and crystal structures of 7 and 8 were determined on the basis of an X-ray diffraction study. Polymerization tests showed that only three complexes ( 6- 8) had activity in the ROP of ε-caprolactone, whereas 1- 5 were inactive in ROP. [ABSTRACT FROM AUTHOR]

2-Mercapto-1,3-benzothiazole (mbztH) may act as a chelating or bridging ligand. In this study, reactions of mbztH with Me3Ga and Me3In were examined. The products were characterized by NMR spectroscopy, elemental analyses, melting point, and molecular weight determinations. Formation of mononuclear chelating complexes Me2M(mbzt) (M = Ga, In) was observed in solutions. Crystallization of Me2M(mbzt) yielded uncommon non-symmetrical dinuclear complexes Me4M2(mbzt)2, in which one metal is bonded to two sulfurs and the other to two nitrogens. [ABSTRACT FROM PUBLISHER]

The reaction of the N- tert -butyl amide of succinic acid with t Bu 3 M (M = Al, Ga) resulted in the formation of the new complexes [Al t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}] ( 1 ), [M t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}( t Bu 3 M)] [M = Al ( 2 ), M = Ga ( 3 ), and [Ga t Bu 2 {N(H)( t Bu)C(O)CH 2 CH 2 COO}] 2 ( 4 ). The aluminum complexes 1 and 2 contained seven-membered C 4 O 2 Al rings with the Al atom bonded to the oxygen atom and coordinated to the nitrogen atom. The reaction of t Bu 3 Ga with the N- tert -butyl amide of succinic acid resulted in the formation of a mixture of 3 and 4 . The gallium complex 3 was isostructural to 2 , whereas the gallium atoms in the dinuclear compound 4 were bonded to the carboxylate oxygens only forming a central Ga 2 C 2 O 4 ring. X-ray studies showed that the crystalline solid obtained after crystallization from the post-reaction mixture was composed of crystals of compound 3 and co-crystals of 3 and 4 . In all reactions, only the OH protons of the ligand reacted with t BuM groups with an alkane evolution, while NH protons remained unreactive. The reaction of t Bu 3 Ga with the N- tert -butyl amide of succinic acid in a 2:1 M ratio of the reagents in the presence of water proceeded with the formation of the unprecedented compound [(Ga t Bu 2 ) 2 (OH){N(H)( t Bu)C(O)CH 2 CH 2 COO}] ( 5 ) as the only product. Compound 5 was also obtained in the hydrolysis reaction of the mixture of compounds 3 and 4 isolated from the post-reaction mixture of t Bu 3 Ga with the N- tert -butyl amide of succinic acid. The molecular and molecular packing in the crystal structures of 1 – 3 and 5 were determined by single-crystal X-ray diffraction. Crystal structure examinations showed laminar structures of 1 , 3 , and 5 and a packed crystal network of 2 . [ABSTRACT FROM AUTHOR]