The aluminum complexes containing two iminophenolate ligands of the type (p-XC 6 H 4 NCHC 6 H 4 O-o) 2 AlR' (R 0 5Me (3, 4) or R 0 5O(CH 2 ) 4 OCH5CH 2 (5, 6), X5H (3, 5), F(4, 6)) were synthesized and characterized by 1 H, 13 C NMR spectroscopy, and X-ray crystallography. The reaction of AlMe 3 with two equivalents of substituted iminophenols gave five-coordinated {ONR} 2 AlMe (3, 4) complexes. Subsequent reaction of these methyl complexes with unsaturated alcohol, HO(CH 2 ) 4 OCH5 CH 2 , resulted in target compounds 5 and 6 in a good yield. It was shown that the complexes (3-6) are monomeric in solution (NMR) and in solid state (X-ray analysis). The catalytic activity of the complexes 5 and 6 towards ring-opening polymerization (ROP) of E-caprolactone and D,L-lactide was assessed. Complex 5 showed higher activity as compared with 6, while both of these catalysts induced controlled homo-and copolymerization to afford the macromonomers with high content of vinyl ether end groups (F n > 80%) in a broad range of molecular weights (M n 5 4000-30,000 g mol 21 ) with relatively narrow MWD (M w / M n 5 1.1-1.5).

The titanium complexes with one (1a, 1b, 1c) and two (2a, 2b) dialkanolamine ligands were used as initiators in the ring-opening polymerization (ROP) of e-caprolactone. Titanocanes 1a and 1b initiated living ROP of e-caprolactone affording polymers whose number-average molecular weights (M n ) increased in direct proportion to monomer conversion (M n 30,000 g mol À1 ) in agreement with calculated values, and were inversely proportional to initiator concentration, while the molecular weight distribution stayed narrow throughout the polymerization (M w /M n 1.2 up to 80% monomer conversion). 1 H-NMR and MALDI-TOF-MS studies of the obtained poly(e-caprolactone)s revealed the presence of an isopropoxy group originated from the initiator at the polymer termini, indicating that the polymerization takes place exclusively at the Ti-O i Pr bond of the catalyst. The higher molecular weight polymers (M n 70,000 g mol À1 ) with reasonable MWD (M w /M n 1.6) were synthesized by living ROP of e-caprolactone using spirobititanocanes (2a, 2b) and titanocane 1c as initiators. The latter catalysts, according MALDI-TOF-MS data, afford poly(e-caprolactone)s with almost equal content of a,x-dihydroxyl-and ahydroxyl-x(carboxylic acid)-terminated chains arising due to monomer insertion into ''Ti-O'' bond of dialkanolamine ligand and from initiation via traces of water, respectively.

The activated anionic ring-opening polymerization of e-caprolactam initiated by 0.35 mol% of combined initiator, i.e., equimolar mixture of magnesium di(e-caprolactamate) (CL 2 Mg) with magnesium halides (MgCl 2 , MgBr 2 , and MgI 2 ) as well as of e-caprolactam magnesium bromide (CLMgBr) in the presence of 0.35 mol% of N-acetyl-e-caprolactam as an activator has been investigated in the temperature range 140-200°C. It was found that the reaction rate increased while the apparent activation energy decreased in the following series: CL 2 Mg/ MgCl 2 \ CL 2 Mg/MgBr 2 * CLMgBr \ CL 2 Mg/MgI 2 . In addition, the poly(ecaprolactam)s prepared with CL 2 Mg/MgX 2 (MgX 2 = MgCl 2 , MgBr 2 , and MgI 2 ) are characterized by slightly higher thermal stability than polymers obtained with CLMgBr as initiator. These observations were explained in terms of the coordination of Lewis acids (MgX 2 , where X = Cl, Br, and I) with imide carbonyl of N-acyllactam end groups leading to the increase of their reactivity and stability.

The new aluminum compounds 1–3 modified by unsaturated alcohol, Me3−nAl(O(CH2)4OCHCH2)n (n = 1 (1), 2 (2), 3 (3)), are synthesized and investigated by multinuclear (1H, 13C, 27Al) NMR spectroscopy. The compounds 1–3 initiate living ring‐opening polymerization of ε‐caprolactone in bulk at 40–80 °C to afford polyesters with controlled molecular weight (Mn up to 35 000 g mol−1) and relatively narrow molecular weight distribution (Mw/Mn < 1.8). Among initiators studied here, aluminum trialkoxide shows the highest activity, whereas aluminum dialkoxide is a less active. In all cases, the fragment of unsaturated alcohol is transferred to the end of the polymeric chain with high degree of functionality (>85%) yielding macromonomers. These macromonomers are copolymerized with maleic anhydride to give poly(vinyl ether‐co‐maleic anhydride)‐g‐poly(ε‐caprolactone) graft copolymers.

In the title structure, [Ti2(C16H16N2O2)2O2]·2CHCl3, the Ti atom is coordinated in a distorted octa­hedral geometry by the O,N,N′,O′ donor set of the salalen ligand and by two μ2-oxide O atoms, which bridge two Ti(salalen) fragments into a centrosymmetric dimeric unit. In the central Ti2(μ2-O)2 fragment, the metal–oxygen distances are significantly different [1.7962 (19) and 1.9292 (19) Å]. In the crystal, the chloro­form mol­ecule is anchored via an N—H⋯Cl and a bifurcated C—H⋯(O,O) hydrogen bond. Slipped π–π stacking [shortest C⋯C distance = 3.585 (4) Å] and C—H⋯π inter­actions contribute to the coherence of the structure.