Synthesis and Structural Characterization of Constrained-Geometry Organolanthanide Chlorides and Alkyls Incorporating the Ligand [η5:σ-(C9H6)C2B10H10]2−
摘要:
Interaction of 1-indenyl-1,2-carborane (1) with 2 equiv of KH in refluxing THF gave the dipotassium salt [K-2][(C9H6)C2B10H10]. Treatment of [K-2][(C9H6)C2B10H10] with 1 equiv of LnCl(3) in THF generated the ionic complex [K(THF)(6)][{eta(5):sigma-(C9H6)C2B10H10}(2)La(THF)] (2) for early lanthanide or organolanthanide chloride complexes [{eta(5):sigma-(C9H6)C2B10H10}Ln(THF)(2)(mu-Cl)(2)K(THF)(2)](2) (Ln = Y (3a), Gd (3b), Er (3c), Yb (3d)) for late lanthanides. Reaction of 3 with nucleophile NaCp or KCH2C6H4-o-NMe2 afforded the corresponding salt metathesis products [eta 5:sigma-(C9H6)C2B10H10]Ln(eta(5)-C5H5)(THF)(2) (Ln = Y (4a), Gd (4b)) or [eta(5):sigma-(C9H6)C2B10H10]Ln(CH2C6H4-o-NMe2)(DME) (Ln = Y (5a), Er (5c)), respectively. Complexes 5 were also synthesized via the alkane elimination reaction of 1-indenyl-1,2-carborane with Ln(CH2C6H4-o-NMe2)(3). They represent the first examples of organolanthanide alkyl complexes incorporating a carboranyl ligand. These complexes were fully characterized by various spectroscopic techniques and elemental analyses. Some were further confirmed by single-crystal X-ray analyses.
Cationic half‐sandwich yttrium alkyl complexes catalyze the ortho‐selective benzylic CH addition of dialkyl pyridines to various olefins, such as ethylene, 1‐hexene, styrenes, and 1,3‐conjugated dienes, to afford new alkylated and allylated pyridine derivatives (see scheme; Cp=C5Me5). A cationic half‐sandwich yttrium picolyl species, such as [CpY(2‐CH2‐6‐CH3C5H3N)]+, has been confirmed to be a key
阳离子半三明治式钇钇烷基络合物催化二烷基吡啶向各种烯烃(如乙烯,1-己烯,苯乙烯和1,3-共轭二烯)的邻位选择性苄基CH加成,以提供新的烷基化和烯丙基化的吡啶衍生物(参见方案; Cp = C 5 Me 5)。阳离子半夹心钇吡啶甲基物种,如[CPY(2-CH 2 -6-CH 3 Ç 5 ħ 3 N)] +,已被证实是在这一转变的关键活性物质。
Asymmetric Yttrium-Catalyzed C(sp<sup>3</sup>)−H Addition of 2-Methyl Azaarenes to Cyclopropenes
An enantioselective C−H addition to a C=C bond represents the most atom‐efficient route for the construction of chiral carbon–carbon skeletons, a central research topic in organic synthesis. We herein report the enantioselective yttrium‐catalyzed C(sp3)−H bond addition of 2‐methyl azaarenes, such as 2‐methyl pyridines, to various substituted cyclopropenes and norbornenes. This process efficiently afforded
C = C键上的对映选择性CH代表手性碳-碳骨架的构建中最有效的原子路线,这是有机合成的主要研究课题。我们在此报告了2-甲基氮杂芳烃(例如2-甲基吡啶)的对映选择性钇催化的C(sp 3)-H键加成到各种取代的环丙烯和降冰片烯上。此过程有效地提供了高收率和高对映选择性(高达ee高达97%)的手性吡啶基甲基官能化的环丙烷和降冰片烷衍生物新家族。
<i>Ortho</i>
‐C–H addition of 2‐substituted pyridines with alkenes and imines enabled by mono(phosphinoamido)‐rare earth complexes
with nonpolar alkenes and polar imines. Upon treatment with one equiv. of borate reagent B(C6F5)3 or [Ph3C][B(C6F5)4], complex NP1-Sc can act as an efficient catalyst for ortho-C–H alkylation of pyridines towards alkenes. In the presence of 1:1 mixed secondary amine of HN (SiMe3)2 and HNBn2, complex NP2-Gd can catalyze ortho-C–H addition of pyridines towards imines, effectively. A wide range of substrates
Monocationic Bis-Alkyl and Bis-Allyl Yttrium Complexes: Synthesis, <sup>89</sup>Y NMR Characterization, Ethylene or Isoprene Polymerization, and Modeling
作者:Alexis D. Oswald、Aymane El Bouhali、Emmanuel Chefdeville、Pierre-Alain R. Breuil、Hélène Olivier-Bourbigou、Julien Thuilliez、Florent Vaultier、Aimery De Mallmann、Mostafa Taoufik、Lionel Perrin、Christophe Boisson
DOI:10.1021/acs.organomet.0c00709
日期:2021.1.25
NMR, and EXAFS for the allyl cationic complex [Y[1,3-(SiMe3)2C3H3]2(THF)2][B(C6F5)4]. More specifically, a 1H-coupled 89Y INEPT sequence has been developed in order to quantify the metal/alkyl ligand stoichiometry of both synthesized neutral tris-alkyl and cationic bis-alkyl yttrium complexes. The activity of the cationic complexes toward ethylene and isoprene homopolymerization has been assessed.
钇与各种双烷基和双烯丙基配体Y(CH 2 SiMe 2 Ph)2(THF)4 ] [B(C 6 F 5)4 ],[Y(CH 2 C 6 H 4 NMe 2)的单阳离子络合物)2(THF)2 ] [B(C 6 F 5)4 ]和[Y [1,3-(SiMe 3)2 C 3 H 3 ] 2(THF)2 ] [B(C 6 F 5)4通过使用硼酸苯胺盐[PhNMe 2 H] [B(C 6 F 5)4 ]质子分解相应的均三烷基或-烯丙基配合物来制备[ ]。所得离子对络合物已通过不同技术进行了分离和表征,例如元素分析,1 H,13 C和89 Y NMR,以及烯丙基阳离子络合物[Y [1,3-(SiMe 3)2 C 3 H 3 ] 2(THF)2 ] [B(C 6 F 5)4 ]。更具体地说,是1为了量化合成的中性三-烷基和阳离子双-烷基钇配合物的金属/烷基配体化学计量,已经开发了H偶联的89 Y INEP