Roitershtein Dmitrii M, Minashina Kseniya I, Minyaev Mikhail E, Ananyev Ivan V, Lyssenko Konstantin A, Tavtorkin Alexander N, Nifant'ev Ilya E
A.V. Topchiev Institute of Petrochemical Synthesis, Russian Academy of Sciences, 29 Leninsky prospect, Moscow 119991, Russian Federation.
Moscow City Pedagogical University, 2nd Selskokhozyaistvenny proezd 4, Moscow 129226, Russian Federation.
Acta Crystallogr C Struct Chem. 2018 Oct 1;74(Pt 10):1105-1115. doi: 10.1107/S2053229618012421. Epub 2018 Sep 13.
A simple and effective synthetic route to homo- and heteroleptic rare-earth (Ln = Y, La and Nd) complexes with a tridentate Schiff base anion has been demonstrated using exchange reactions of rare-earth chlorides with in-situ-generated sodium (E)-2-{[(2-methoxyphenyl)imino]methyl}phenoxide in different molar ratios in absolute methanol. Five crystal structures have been determined and studied, namely tris(2-{[(2-methoxyphenyl)imino]methyl}phenolato-κO,N,O)lanthanum, [La(CHNO)], (1), tris(2-{[(2-methoxyphenyl)imino]methyl}phenolato-κO,N,O)neodymium tetrahydrofuran disolvate, [La(CHNO)]·2CHO, (2)·2THF, tris(2-{[(2-methoxyphenyl)imino]methyl}phenolato)-κO,N,O;κO,N,O;κN,O-yttrium, [Y(CHNO)], (3), dichlorido-1κCl,2κCl-μ-methanolato-1:2κO:O-methanol-2κO-(μ-2-{[(2-methoxyphenyl)imino]methyl}phenolato-1κO,N,O:2κO)bis(2-{[(2-methoxyphenyl)imino]methyl}phenolato)-1κO,N,O;2κO,N,O-diyttrium-tetrahydrofuran-methanol (1/1/1), [Y(CHNO)(CHO)Cl(CHO)]·CHO·CHO, (4)·MeOH·THF, and bis(μ-2-{[(2-methoxyphenyl)imino]methyl}phenolato-1κO,N,O:2κO)bis(2-{[(2-methoxyphenyl)imino]methyl}phenolato-2κO,N,O)sodiumyttrium chloroform disolvate, [NaY(CHNO)]·2CHCl, (5)·2CHCl. Structural peculiarities of homoleptic tris(iminophenoxide)s (1)-(3), binuclear tris(iminophenoxide) (4) and homoleptic ate tetrakis(iminophenoxide) (5) are discussed. The nonflat Schiff base ligand displays μ-κO,N,O:κO bridging, and κO,N,O and κN,O terminal coordination modes, depending on steric congestion, which in turn depends on the ionic radii of the rare-earth metals and the number of coordinated ligands. It has been demonstrated that interligand dihedral angles of the phenoxide ligand are convenient for comparing steric hindrance in complexes. (4)·MeOH has a flat YO rhomboid core and exhibits both inter- and intramolecular MeO-H...Cl hydrogen bonding. Catalytic systems based on complexes (1)-(3) and (5) have demonstrated medium catalytic performance in acrylonitrile polymerization, providing polyacrylonitrile samples with narrow polydispersity.
通过稀土氯化物与在绝对甲醇中以不同摩尔比原位生成的（E）-2-{[（2-甲氧基苯基）亚氨基]甲基}苯氧基钠进行交换反应，展示了一种简单有效的合成路线，用于制备具有三齿席夫碱阴离子的均配和异配稀土（Ln = Y、La和Nd）配合物。已测定并研究了五种晶体结构，即三（2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根-κO，N，O）镧，[La（CHNO）]，（1）；三（2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根-κO，N，O）钕四氢呋喃二溶剂合物，[La（CHNO）]·2CHO，（2）·2THF；三（2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根）-κO，N，O；κO，N，O；κN，O-钇，[Y（CHNO）]，（3）；二氯-1κCl，2κCl-μ-甲醇根-1:2κO:O-甲醇-2κO-（μ-2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根-1κO，N，O:2κO）双（2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根）-1κO，N，O；2κO，N，O-二钇-四氢呋喃-甲醇（1/1/1），[Y（CHNO）（CHO）Cl（CHO）]·CHO·CHO，（4）·MeOH·THF；以及双（μ-2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根-1κO，N，O:2κO）双（2-{[（2-甲氧基苯基）亚氨基]甲基}苯酚根-2κO，N，O）钠钇氯仿二溶剂合物，[NaY（CHNO）]·2CHCl，（5）·2CHCl。讨论了均配三（亚氨基苯酚根）（1）-（3）单核、双核三（亚氨基苯酚根）（4）和均配酸式四（亚氨基苯酚根）（5）的结构特点。非平面席夫碱配体根据空间拥挤情况呈现μ-κO，N，O:κO桥连以及κO，N，O和κN，O末端配位模式，而空间拥挤又取决于稀土金属的离子半径和配位配体的数量。已证明，酚氧基配体的配体间二面角便于比较配合物中的空间位阻。（4）·MeOH具有扁平的YO菱形核心，并表现出分子间和分子内的MeO-H...Cl氢键。基于配合物（1）-（3）和（5）的催化体系在丙烯腈聚合反应中表现出中等催化性能，得到了具有窄多分散性的聚丙烯腈样品。
