Reactions of phosphines with electron deficient boranes
作者:Gregory C. Welch、Roberto Prieto、Meghan A. Dureen、Alan J. Lough、Oijsamola A. Labeodan、Thorsten Höltrichter-Rössmann、Douglas W. Stephan
DOI:10.1039/b814486a
日期:——
A series of classical B(C(6)F(5))(3)-phosphine adducts are shown to be reactive molecules. Reaction of (THF)B(C(6)F(5))(3) with phosphines are shown to effect ring-opening of THF affording the zwitterionic phosphonium-borate species of the form R(2)PH(C(4)H(8)O)B(C(6)F(5))(3) and R(3)P(C(4)H(8)O)B(C(6)F(5))(3). Alternatively, treatment of (THF)B(C(6)F(5))(3) with a lithium phosphide (R(2)PLi, R = tBu
Iridium(I) Complexes with Anionic N-Heterocyclic Carbene Ligands as Catalysts for the Hydrogenation of Alkenes in Nonpolar Media
作者:Eugene L. Kolychev、Sabrina Kronig、Kai Brandhorst、Matthias Freytag、Peter G. Jones、Matthias Tamm
DOI:10.1021/ja406529c
日期:2013.8.21
complexes of anionic N-heterocycliccarbenes that contain a weakly coordinating borate moiety (WCA-NHC) was prepared in one step from free N-heterocycliccarbenes by deprotonation with n-butyl lithium followed by borane addition. The reaction of the resulting lithium-carbene adducts with [M(COD)Cl]2 (M = Rh, Ir; COD = 1,5-cyclooctadiene) afforded zwitterionic rhodium(I) and iridium(I) complexes of the
Lewis-Acidity of Trimethylplatinum(IV) with Labile Oxygen-Donor Ligands
作者:Vicki Hsieh、Antonio G. De Crisci、Alan J. Lough、Ulrich Fekl
DOI:10.1021/om060787n
日期:2007.2.1
trimethyl platinum(IV) center (27% of the acidity of BBr3) and commensurate (moderate) intrinsic catalytic activity of the trimethylplatinum(IV) unit. Crystals of an aldehyde adduct were obtained. X-ray crystallography shows a binuclear metal complex, [Me3Pt(crotonaldehyde)(μ-OTf)}2]. Despite the relatively low Lewis-acidity, in the absence of oxygen-donor ligands, the trimethylplatinum(IV) is capable
研究了具有不稳定配体和弱配位阴离子的三甲基铂(IV)系统的路易斯酸度和充当路易斯酸性催化剂的能力。四聚体trimethylplatinum(IV)三氟甲磺酸酯的路易斯酸度(三氟甲磺酸酯=三氟甲烷磺酸酯,OTF),[我3 PtOTf} 4 ],向羰基化合物用NMR滴定与CD巴豆醛(童车方法)定量2氯2。数据显示三甲基铂(IV)中心的路易斯酸度适中但很重要(BBr 3酸度的27%)和三甲基铂(IV)单元的同等(中等)固有催化活性。得到醛加成物的晶体。X射线晶体学显示双核金属络合物[Me 3 Pt(巴豆醛)(μ-OTf)} 2 ]。尽管路易斯酸相对较低,但在没有氧供体配体的情况下,三甲基铂(IV)能够分解[B(Ar F)4 ] -阴离子(Ar F = 3,5-(CF 3)2 C 6 H 3),显然是通过芳基提取生成B(Ar F)3。[Me 3 PtOTf}的盐复分解反应4 ]用Na [B(AR
Boron Lewis Acid-Catalyzed Hydroboration of Alkenes with Pinacolborane: BAr<sup>F</sup><sub>3</sub>Does What B(C<sub>6</sub>F<sub>5</sub>)<sub>3</sub>Cannot Do!
作者:Qin Yin、Sebastian Kemper、Hendrik F. T. Klare、Martin Oestreich
DOI:10.1002/chem.201603466
日期:2016.9.19
(BArF3) is reported. The choice of the boron Lewisacid is crucial as the more prominent boron Lewisacid tris(pentafluorophenyl)borane (B(C6F5)3) is reluctant to react. Unlike B(C6F5)3, BArF3 is found to engage in substituent redistribution with HBpin, resulting in the formation of ArFBpin and the electron‐deficient diboranes [H2BArF]2 and [(ArF)(H)B(μ‐H)2BArF2]. These in situ‐generated hydroboranes
报道了由三[3,5-双(三氟甲基)苯基]硼烷(BAr F 3)引发的频哪醇硼烷(HBpin)对各种烯烃的无过渡金属氢硼化。硼路易斯酸的选择是至关重要的,因为更突出的硼路易斯酸三(五氟苯基)硼烷(B(C 6 F 5)3)不愿反应。与B(C 6 F 5)3不同,发现BAr F 3与HBpin参与取代基的重新分布,导致形成Ar F Bpin和缺电子的乙硼烷[H 2 BAr F ] 2和[(Ar F)(H)B(μ‐ H)2 BAr F 2 ]。这些原位生成的氢硼烷经历了顺式非对映选择性的苯乙烯衍生物以及脂族烯烃的区域选择性氢硼化。这些加合物与HBpin的另一种配位复分解随后提供了相应的HBpin衍生的反马尔科夫尼科夫加合物。反应性氢硼烷在该步骤中再生,从而关闭催化循环。
Experimental and quantum chemical studies of anionic analogues of N-heterocyclic carbenes
作者:Haoyu Niu、Robert J. Mangan、Andrey V. Protchenko、Nicholas Phillips、Wiebke Unkrig、Christian Friedmann、Eugene L. Kolychev、Rémi Tirfoin、Jamie Hicks、Simon Aldridge
DOI:10.1039/c8dt01661e
日期:——
series of anionicligands related to the well known N-heterocyclic carbene (NHC) class of donor. Analyses of (i) the respective frontier orbital energies/compositions for the ‘free’ ligands and the results of ETS-NOCV studies of the bonding in model group 11 complexes; and (ii) the structural metrics for (new) linear gold(I) compounds, have been used to probe the bonding in complexes of NHCligands which